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prefect.settings

Prefect settings management.

Each setting is defined as a Setting type. The name of each setting is stylized in all caps, matching the environment variable that can be used to change the setting.

All settings defined in this file are used to generate a dynamic Pydantic settings class called Settings. When instantiated, this class will load settings from environment variables and pull default values from the setting definitions.

The current instance of Settings being used by the application is stored in a SettingsContext model which allows each instance of the Settings class to be accessed in an async-safe manner.

Aside from environment variables, we allow settings to be changed during the runtime of the process using profiles. Profiles contain setting overrides that the user may persist without setting environment variables. Profiles are also used internally for managing settings during task run execution where differing settings may be used concurrently in the same process and during testing where we need to override settings to ensure their value is respected as intended.

The SettingsContext is set when the prefect module is imported. This context is referred to as the "root" settings context for clarity. Generally, this is the only settings context that will be used. When this context is entered, we will instantiate a Settings object, loading settings from environment variables and defaults, then we will load the active profile and use it to override settings. See enter_root_settings_context for details on determining the active profile.

Another SettingsContext may be entered at any time to change the settings being used by the code within the context. Generally, users should not use this. Settings management should be left to Prefect application internals.

Generally, settings should be accessed with SETTING_VARIABLE.value() which will pull the current Settings instance from the current SettingsContext and retrieve the value of the relevant setting.

Accessing a setting's value will also call the Setting.value_callback which allows settings to be dynamically modified on retrieval. This allows us to make settings dependent on the value of other settings or perform other dynamic effects.

PREFECT_HOME = Setting(Path, default=Path('~') / '.prefect', value_callback=expanduser_in_path) module-attribute

Prefect's home directory. Defaults to ~/.prefect. This directory may be created automatically when required.

PREFECT_EXTRA_ENTRYPOINTS = Setting(str, default='') module-attribute

Modules for Prefect to import when Prefect is imported.

Values should be separated by commas, e.g. my_module,my_other_module. Objects within modules may be specified by a ':' partition, e.g. my_module:my_object. If a callable object is provided, it will be called with no arguments on import.

PREFECT_DEBUG_MODE = Setting(bool, default=False) module-attribute

If True, places the API in debug mode. This may modify behavior to facilitate debugging, including extra logs and other verbose assistance. Defaults to False.

PREFECT_CLI_COLORS = Setting(bool, default=True) module-attribute

If True, use colors in CLI output. If False, output will not include colors codes. Defaults to True.

PREFECT_CLI_PROMPT = Setting(Optional[bool], default=None) module-attribute

If True, use interactive prompts in CLI commands. If False, no interactive prompts will be used. If None, the value will be dynamically determined based on the presence of an interactive-enabled terminal.

PREFECT_CLI_WRAP_LINES = Setting(bool, default=True) module-attribute

If True, wrap text by inserting new lines in long lines in CLI output. If False, output will not be wrapped. Defaults to True.

PREFECT_TEST_MODE = Setting(bool, default=False) module-attribute

If True, places the API in test mode. This may modify behavior to facilitate testing. Defaults to False.

PREFECT_UNIT_TEST_MODE = Setting(bool, default=False) module-attribute

This variable only exists to facilitate unit testing. If True, code is executing in a unit test context. Defaults to False.

PREFECT_UNIT_TEST_LOOP_DEBUG = Setting(bool, default=True) module-attribute

If True turns on debug mode for the unit testing event loop. Defaults to False.

PREFECT_TEST_SETTING = Setting(Any, default=None, value_callback=only_return_value_in_test_mode) module-attribute

This variable only exists to facilitate testing of settings. If accessed when PREFECT_TEST_MODE is not set, None is returned.

PREFECT_API_TLS_INSECURE_SKIP_VERIFY = Setting(bool, default=False) module-attribute

If True, disables SSL checking to allow insecure requests. This is recommended only during development, e.g. when using self-signed certificates.

PREFECT_API_SSL_CERT_FILE = Setting(str, default=os.environ.get('SSL_CERT_FILE')) module-attribute

This configuration settings option specifies the path to an SSL certificate file. When set, it allows the application to use the specified certificate for secure communication. If left unset, the setting will default to the value provided by the SSL_CERT_FILE environment variable.

PREFECT_API_URL = Setting(str, default=None) module-attribute

If provided, the URL of a hosted Prefect API. Defaults to None.

When using Prefect Cloud, this will include an account and workspace.

PREFECT_SILENCE_API_URL_MISCONFIGURATION = Setting(bool, default=False) module-attribute

If True, disable the warning when a user accidentally misconfigure its PREFECT_API_URL Sometimes when a user manually set PREFECT_API_URL to a custom url,reverse-proxy for example, we would like to silence this warning so we will set it to FALSE.

PREFECT_API_KEY = Setting(str, default=None, is_secret=True) module-attribute

API key used to authenticate with a the Prefect API. Defaults to None.

PREFECT_API_ENABLE_HTTP2 = Setting(bool, default=False) module-attribute

If true, enable support for HTTP/2 for communicating with an API.

If the API does not support HTTP/2, this will have no effect and connections will be made via HTTP/1.1.

PREFECT_CLIENT_MAX_RETRIES = Setting(int, default=5) module-attribute

The maximum number of retries to perform on failed HTTP requests.

Defaults to 5. Set to 0 to disable retries.

See PREFECT_CLIENT_RETRY_EXTRA_CODES for details on which HTTP status codes are retried.

PREFECT_CLIENT_RETRY_JITTER_FACTOR = Setting(float, default=0.2) module-attribute

A value greater than or equal to zero to control the amount of jitter added to retried client requests. Higher values introduce larger amounts of jitter.

Set to 0 to disable jitter. See clamped_poisson_interval for details on the how jitter can affect retry lengths.

PREFECT_CLIENT_RETRY_EXTRA_CODES = Setting(str, default='', value_callback=status_codes_as_integers_in_range) module-attribute

A comma-separated list of extra HTTP status codes to retry on. Defaults to an empty string. 429, 502 and 503 are always retried. Please note that not all routes are idempotent and retrying may result in unexpected behavior.

PREFECT_CLIENT_CSRF_SUPPORT_ENABLED = Setting(bool, default=True) module-attribute

Determines if CSRF token handling is active in the Prefect client for API requests.

When enabled (True), the client automatically manages CSRF tokens by retrieving, storing, and including them in applicable state-changing requests (POST, PUT, PATCH, DELETE) to the API.

Disabling this setting (False) means the client will not handle CSRF tokens, which might be suitable for environments where CSRF protection is disabled.

Defaults to True, ensuring CSRF protection is enabled by default.

PREFECT_CLOUD_API_URL = Setting(str, default='https://api.prefect.cloud/api', value_callback=check_for_deprecated_cloud_url) module-attribute

API URL for Prefect Cloud. Used for authentication.

PREFECT_CLOUD_URL = Setting(str, default=None, deprecated=True, deprecated_start_date='Dec 2022', deprecated_help='Use `PREFECT_CLOUD_API_URL` instead.') module-attribute

PREFECT_UI_URL = Setting(Optional[str], default=None, value_callback=default_ui_url) module-attribute

The URL for the UI. By default, this is inferred from the PREFECT_API_URL.

When using Prefect Cloud, this will include the account and workspace. When using an ephemeral server, this will be None.

PREFECT_CLOUD_UI_URL = Setting(str, default=None, value_callback=default_cloud_ui_url) module-attribute

The URL for the Cloud UI. By default, this is inferred from the PREFECT_CLOUD_API_URL.

PREFECT_UI_URL will be workspace specific and will be usable in the open source too.

In contrast, this value is only valid for Cloud and will not include the workspace.

PREFECT_API_REQUEST_TIMEOUT = Setting(float, default=60.0) module-attribute

The default timeout for requests to the API

PREFECT_EXPERIMENTAL_WARN = Setting(bool, default=True) module-attribute

If enabled, warn on usage of experimental features.

PREFECT_PROFILES_PATH = Setting(Path, default=Path('${PREFECT_HOME}') / 'profiles.toml', value_callback=template_with_settings(PREFECT_HOME)) module-attribute

The path to a profiles configuration files.

PREFECT_RESULTS_DEFAULT_SERIALIZER = Setting(str, default='pickle') module-attribute

The default serializer to use when not otherwise specified.

PREFECT_RESULTS_PERSIST_BY_DEFAULT = Setting(bool, default=False) module-attribute

The default setting for persisting results when not otherwise specified. If enabled, flow and task results will be persisted unless they opt out.

PREFECT_TASKS_REFRESH_CACHE = Setting(bool, default=False) module-attribute

If True, enables a refresh of cached results: re-executing the task will refresh the cached results. Defaults to False.

PREFECT_TASK_DEFAULT_RETRIES = Setting(int, default=0) module-attribute

This value sets the default number of retries for all tasks. This value does not overwrite individually set retries values on tasks

PREFECT_FLOW_DEFAULT_RETRIES = Setting(int, default=0) module-attribute

This value sets the default number of retries for all flows. This value does not overwrite individually set retries values on a flow

PREFECT_FLOW_DEFAULT_RETRY_DELAY_SECONDS = Setting(Union[int, float], default=0) module-attribute

This value sets the retry delay seconds for all flows. This value does not overwrite individually set retry delay seconds

PREFECT_TASK_DEFAULT_RETRY_DELAY_SECONDS = Setting(Union[float, int, List[float]], default=0) module-attribute

This value sets the default retry delay seconds for all tasks. This value does not overwrite individually set retry delay seconds

PREFECT_TASK_RUN_TAG_CONCURRENCY_SLOT_WAIT_SECONDS = Setting(int, default=30) module-attribute

The number of seconds to wait before retrying when a task run cannot secure a concurrency slot from the server.

PREFECT_LOCAL_STORAGE_PATH = Setting(Path, default=Path('${PREFECT_HOME}') / 'storage', value_callback=template_with_settings(PREFECT_HOME)) module-attribute

The path to a block storage directory to store things in.

PREFECT_MEMO_STORE_PATH = Setting(Path, default=Path('${PREFECT_HOME}') / 'memo_store.toml', value_callback=template_with_settings(PREFECT_HOME)) module-attribute

The path to the memo store file.

PREFECT_MEMOIZE_BLOCK_AUTO_REGISTRATION = Setting(bool, default=True) module-attribute

Controls whether or not block auto-registration on start up should be memoized. Setting to False may result in slower server start up times.

PREFECT_LOGGING_LEVEL = Setting(str, default='INFO', value_callback=debug_mode_log_level) module-attribute

The default logging level for Prefect loggers. Defaults to "INFO" during normal operation. Is forced to "DEBUG" during debug mode.

PREFECT_LOGGING_INTERNAL_LEVEL = Setting(str, default='ERROR', value_callback=debug_mode_log_level) module-attribute

The default logging level for Prefect's internal machinery loggers. Defaults to "ERROR" during normal operation. Is forced to "DEBUG" during debug mode.

PREFECT_LOGGING_SERVER_LEVEL = Setting(str, default='WARNING') module-attribute

The default logging level for the Prefect API server.

PREFECT_LOGGING_SETTINGS_PATH = Setting(Path, default=Path('${PREFECT_HOME}') / 'logging.yml', value_callback=template_with_settings(PREFECT_HOME)) module-attribute

The path to a custom YAML logging configuration file. If no file is found, the default logging.yml is used. Defaults to a logging.yml in the Prefect home directory.

PREFECT_LOGGING_EXTRA_LOGGERS = Setting(str, default='', value_callback=get_extra_loggers) module-attribute

Additional loggers to attach to Prefect logging at runtime. Values should be comma separated. The handlers attached to the 'prefect' logger will be added to these loggers. Additionally, if the level is not set, it will be set to the same level as the 'prefect' logger.

PREFECT_LOGGING_LOG_PRINTS = Setting(bool, default=False) module-attribute

If set, print statements in flows and tasks will be redirected to the Prefect logger for the given run. This setting can be overridden by individual tasks and flows.

PREFECT_LOGGING_TO_API_ENABLED = Setting(bool, default=True) module-attribute

Toggles sending logs to the API. If False, logs sent to the API log handler will not be sent to the API.

PREFECT_LOGGING_TO_API_BATCH_INTERVAL = Setting(float, default=2.0) module-attribute

The number of seconds between batched writes of logs to the API.

PREFECT_LOGGING_TO_API_BATCH_SIZE = Setting(int, default=4000000) module-attribute

The maximum size in bytes for a batch of logs.

PREFECT_LOGGING_TO_API_MAX_LOG_SIZE = Setting(int, default=1000000) module-attribute

The maximum size in bytes for a single log.

PREFECT_LOGGING_TO_API_WHEN_MISSING_FLOW = Setting(Literal['warn', 'error', 'ignore'], default='warn') module-attribute

Controls the behavior when loggers attempt to send logs to the API handler from outside of a flow.

All logs sent to the API must be associated with a flow run. The API log handler can only be used outside of a flow by manually providing a flow run identifier. Logs that are not associated with a flow run will not be sent to the API. This setting can be used to determine if a warning or error is displayed when the identifier is missing.

The following options are available:

  • "warn": Log a warning message.
  • "error": Raise an error.
  • "ignore": Do not log a warning message or raise an error.

PREFECT_SQLALCHEMY_POOL_SIZE = Setting(int, default=None) module-attribute

Controls connection pool size when using a PostgreSQL database with the Prefect API. If not set, the default SQLAlchemy pool size will be used.

PREFECT_SQLALCHEMY_MAX_OVERFLOW = Setting(int, default=None) module-attribute

Controls maximum overflow of the connection pool when using a PostgreSQL database with the Prefect API. If not set, the default SQLAlchemy maximum overflow value will be used.

PREFECT_LOGGING_COLORS = Setting(bool, default=True) module-attribute

Whether to style console logs with color.

PREFECT_LOGGING_MARKUP = Setting(bool, default=False) module-attribute

Whether to interpret strings wrapped in square brackets as a style. This allows styles to be conveniently added to log messages, e.g. [red]This is a red message.[/red]. However, the downside is, if enabled, strings that contain square brackets may be inaccurately interpreted and lead to incomplete output, e.g. DROP TABLE [dbo].[SomeTable];" outputs DROP TABLE .[SomeTable];.

PREFECT_TASK_INTROSPECTION_WARN_THRESHOLD = Setting(float, default=10.0) module-attribute

Threshold time in seconds for logging a warning if task parameter introspection exceeds this duration. Parameter introspection can be a significant performance hit when the parameter is a large collection object, e.g. a large dictionary or DataFrame, and each element needs to be inspected. See prefect.utilities.annotations.quote for more details. Defaults to 10.0. Set to 0 to disable logging the warning.

PREFECT_AGENT_QUERY_INTERVAL = Setting(float, default=15) module-attribute

The agent loop interval, in seconds. Agents will check for new runs this often. Defaults to 15.

PREFECT_AGENT_PREFETCH_SECONDS = Setting(int, default=15) module-attribute

Agents will look for scheduled runs this many seconds in the future and attempt to run them. This accounts for any additional infrastructure spin-up time or latency in preparing a flow run. Note flow runs will not start before their scheduled time, even if they are prefetched. Defaults to 15.

PREFECT_ASYNC_FETCH_STATE_RESULT = Setting(bool, default=False) module-attribute

Determines whether State.result() fetches results automatically or not. In Prefect 2.6.0, the State.result() method was updated to be async to facilitate automatic retrieval of results from storage which means when writing async code you must await the call. For backwards compatibility, the result is not retrieved by default for async users. You may opt into this per call by passing fetch=True or toggle this setting to change the behavior globally. This setting does not affect users writing synchronous tasks and flows. This setting does not affect retrieval of results when using Future.result().

PREFECT_API_BLOCKS_REGISTER_ON_START = Setting(bool, default=True) module-attribute

If set, any block types that have been imported will be registered with the backend on application startup. If not set, block types must be manually registered.

PREFECT_API_DATABASE_PASSWORD = Setting(str, default=None, is_secret=True) module-attribute

Password to template into the PREFECT_API_DATABASE_CONNECTION_URL. This is useful if the password must be provided separately from the connection URL. To use this setting, you must include it in your connection URL.

PREFECT_API_DATABASE_CONNECTION_URL = Setting(str, default=None, value_callback=default_database_connection_url, is_secret=True) module-attribute

A database connection URL in a SQLAlchemy-compatible format. Prefect currently supports SQLite and Postgres. Note that all Prefect database engines must use an async driver - for SQLite, use sqlite+aiosqlite and for Postgres use postgresql+asyncpg.

SQLite in-memory databases can be used by providing the url sqlite+aiosqlite:///file::memory:?cache=shared&uri=true&check_same_thread=false, which will allow the database to be accessed by multiple threads. Note that in-memory databases can not be accessed from multiple processes and should only be used for simple tests.

Defaults to a sqlite database stored in the Prefect home directory.

If you need to provide password via a different environment variable, you use the PREFECT_API_DATABASE_PASSWORD setting. For example:

PREFECT_API_DATABASE_PASSWORD='mypassword'
PREFECT_API_DATABASE_CONNECTION_URL='postgresql+asyncpg://postgres:${PREFECT_API_DATABASE_PASSWORD}@localhost/prefect'

PREFECT_API_DATABASE_ECHO = Setting(bool, default=False) module-attribute

If True, SQLAlchemy will log all SQL issued to the database. Defaults to False.

PREFECT_API_DATABASE_MIGRATE_ON_START = Setting(bool, default=True) module-attribute

If True, the database will be upgraded on application creation. If False, the database will need to be upgraded manually.

PREFECT_API_DATABASE_TIMEOUT = Setting(Optional[float], default=10.0) module-attribute

A statement timeout, in seconds, applied to all database interactions made by the API. Defaults to 10 seconds.

PREFECT_API_DATABASE_CONNECTION_TIMEOUT = Setting(Optional[float], default=5) module-attribute

A connection timeout, in seconds, applied to database connections. Defaults to 5.

PREFECT_API_SERVICES_SCHEDULER_LOOP_SECONDS = Setting(float, default=60) module-attribute

The scheduler loop interval, in seconds. This determines how often the scheduler will attempt to schedule new flow runs, but has no impact on how quickly either flow runs or task runs are actually executed. Defaults to 60.

PREFECT_API_SERVICES_SCHEDULER_DEPLOYMENT_BATCH_SIZE = Setting(int, default=100) module-attribute

The number of deployments the scheduler will attempt to schedule in a single batch. If there are more deployments than the batch size, the scheduler immediately attempts to schedule the next batch; it does not sleep for scheduler_loop_seconds until it has visited every deployment once. Defaults to 100.

PREFECT_API_SERVICES_SCHEDULER_MAX_RUNS = Setting(int, default=100) module-attribute

The scheduler will attempt to schedule up to this many auto-scheduled runs in the future. Note that runs may have fewer than this many scheduled runs, depending on the value of scheduler_max_scheduled_time. Defaults to 100.

PREFECT_API_SERVICES_SCHEDULER_MIN_RUNS = Setting(int, default=3) module-attribute

The scheduler will attempt to schedule at least this many auto-scheduled runs in the future. Note that runs may have more than this many scheduled runs, depending on the value of scheduler_min_scheduled_time. Defaults to 3.

PREFECT_API_SERVICES_SCHEDULER_MAX_SCHEDULED_TIME = Setting(timedelta, default=timedelta(days=100)) module-attribute

The scheduler will create new runs up to this far in the future. Note that this setting will take precedence over scheduler_max_runs: if a flow runs once a month and scheduler_max_scheduled_time is three months, then only three runs will be scheduled. Defaults to 100 days (8640000 seconds).

PREFECT_API_SERVICES_SCHEDULER_MIN_SCHEDULED_TIME = Setting(timedelta, default=timedelta(hours=1)) module-attribute

The scheduler will create new runs at least this far in the future. Note that this setting will take precedence over scheduler_min_runs: if a flow runs every hour and scheduler_min_scheduled_time is three hours, then three runs will be scheduled even if scheduler_min_runs is 1. Defaults to 1 hour (3600 seconds).

PREFECT_API_SERVICES_SCHEDULER_INSERT_BATCH_SIZE = Setting(int, default=500) module-attribute

The number of flow runs the scheduler will attempt to insert in one batch across all deployments. If the number of flow runs to schedule exceeds this amount, the runs will be inserted in batches of this size. Defaults to 500.

PREFECT_API_SERVICES_LATE_RUNS_LOOP_SECONDS = Setting(float, default=5) module-attribute

The late runs service will look for runs to mark as late this often. Defaults to 5.

PREFECT_API_SERVICES_LATE_RUNS_AFTER_SECONDS = Setting(timedelta, default=timedelta(seconds=15)) module-attribute

The late runs service will mark runs as late after they have exceeded their scheduled start time by this many seconds. Defaults to 5 seconds.

PREFECT_API_SERVICES_PAUSE_EXPIRATIONS_LOOP_SECONDS = Setting(float, default=5) module-attribute

The pause expiration service will look for runs to mark as failed this often. Defaults to 5.

PREFECT_API_SERVICES_CANCELLATION_CLEANUP_LOOP_SECONDS = Setting(float, default=20) module-attribute

The cancellation cleanup service will look non-terminal tasks and subflows this often. Defaults to 20.

PREFECT_API_SERVICES_FOREMAN_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the Foreman service in the server application.

PREFECT_API_SERVICES_FOREMAN_LOOP_SECONDS = Setting(float, default=15) module-attribute

The number of seconds to wait between each iteration of the Foreman loop which checks for offline workers and updates work pool status.

PREFECT_API_SERVICES_FOREMAN_INACTIVITY_HEARTBEAT_MULTIPLE = Setting(int, default=3) module-attribute

The number of heartbeats that must be missed before a worker is marked as offline.

PREFECT_API_SERVICES_FOREMAN_FALLBACK_HEARTBEAT_INTERVAL_SECONDS = Setting(int, default=30) module-attribute

The number of seconds to use for online/offline evaluation if a worker's heartbeat interval is not set.

PREFECT_API_SERVICES_FOREMAN_DEPLOYMENT_LAST_POLLED_TIMEOUT_SECONDS = Setting(int, default=60) module-attribute

The number of seconds before a deployment is marked as not ready if it has not been polled.

PREFECT_API_SERVICES_FOREMAN_WORK_QUEUE_LAST_POLLED_TIMEOUT_SECONDS = Setting(int, default=60) module-attribute

The number of seconds before a work queue is marked as not ready if it has not been polled.

PREFECT_API_DEFAULT_LIMIT = Setting(int, default=200) module-attribute

The default limit applied to queries that can return multiple objects, such as POST /flow_runs/filter.

PREFECT_SERVER_API_HOST = Setting(str, default='127.0.0.1') module-attribute

The API's host address (defaults to 127.0.0.1).

PREFECT_SERVER_API_PORT = Setting(int, default=4200) module-attribute

The API's port address (defaults to 4200).

PREFECT_SERVER_API_KEEPALIVE_TIMEOUT = Setting(int, default=5) module-attribute

The API's keep alive timeout (defaults to 5). Refer to https://www.uvicorn.org/settings/#timeouts for details.

When the API is hosted behind a load balancer, you may want to set this to a value greater than the load balancer's idle timeout.

Note this setting only applies when calling prefect server start; if hosting the API with another tool you will need to configure this there instead.

PREFECT_SERVER_CSRF_PROTECTION_ENABLED = Setting(bool, default=False) module-attribute

Controls the activation of CSRF protection for the Prefect server API.

When enabled (True), the server enforces CSRF validation checks on incoming state-changing requests (POST, PUT, PATCH, DELETE), requiring a valid CSRF token to be included in the request headers or body. This adds a layer of security by preventing unauthorized or malicious sites from making requests on behalf of authenticated users.

It is recommended to enable this setting in production environments where the API is exposed to web clients to safeguard against CSRF attacks.

Note: Enabling this setting requires corresponding support in the client for CSRF token management. See PREFECT_CLIENT_CSRF_SUPPORT_ENABLED for more.

PREFECT_SERVER_CSRF_TOKEN_EXPIRATION = Setting(timedelta, default=timedelta(hours=1)) module-attribute

Specifies the duration for which a CSRF token remains valid after being issued by the server.

The default expiration time is set to 1 hour, which offers a reasonable compromise. Adjust this setting based on your specific security requirements and usage patterns.

PREFECT_UI_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to serve the Prefect UI.

PREFECT_UI_API_URL = Setting(str, default=None, value_callback=default_ui_api_url) module-attribute

The connection url for communication from the UI to the API. Defaults to PREFECT_API_URL if set. Otherwise, the default URL is generated from PREFECT_SERVER_API_HOST and PREFECT_SERVER_API_PORT. If providing a custom value, the aforementioned settings may be templated into the given string.

PREFECT_SERVER_ANALYTICS_ENABLED = Setting(bool, default=True) module-attribute

When enabled, Prefect sends anonymous data (e.g. count of flow runs, package version) on server startup to help us improve our product.

PREFECT_API_SERVICES_SCHEDULER_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the scheduling service in the server application. If disabled, you will need to run this service separately to schedule runs for deployments.

PREFECT_API_SERVICES_LATE_RUNS_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the late runs service in the server application. If disabled, you will need to run this service separately to have runs past their scheduled start time marked as late.

PREFECT_API_SERVICES_FLOW_RUN_NOTIFICATIONS_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the flow run notifications service in the server application. If disabled, you will need to run this service separately to send flow run notifications.

PREFECT_API_SERVICES_PAUSE_EXPIRATIONS_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the paused flow run expiration service in the server application. If disabled, paused flows that have timed out will remain in a Paused state until a resume attempt.

PREFECT_API_TASK_CACHE_KEY_MAX_LENGTH = Setting(int, default=2000) module-attribute

The maximum number of characters allowed for a task run cache key. This setting cannot be changed client-side, it must be set on the server.

PREFECT_API_SERVICES_CANCELLATION_CLEANUP_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the cancellation cleanup service in the server application. If disabled, task runs and subflow runs belonging to cancelled flows may remain in non-terminal states.

PREFECT_API_MAX_FLOW_RUN_GRAPH_NODES = Setting(int, default=10000) module-attribute

The maximum size of a flow run graph on the v2 API

PREFECT_API_MAX_FLOW_RUN_GRAPH_ARTIFACTS = Setting(int, default=10000) module-attribute

The maximum number of artifacts to show on a flow run graph on the v2 API

PREFECT_EXPERIMENTAL_ENABLE_ARTIFACTS_ON_FLOW_RUN_GRAPH = Setting(bool, default=True) module-attribute

Whether or not to enable artifacts on the flow run graph.

PREFECT_EXPERIMENTAL_ENABLE_STATES_ON_FLOW_RUN_GRAPH = Setting(bool, default=True) module-attribute

Whether or not to enable flow run states on the flow run graph.

PREFECT_EXPERIMENTAL_ENABLE_WORK_POOLS = Setting(bool, default=True) module-attribute

Whether or not to enable experimental Prefect work pools.

PREFECT_EXPERIMENTAL_WARN_WORK_POOLS = Setting(bool, default=False) module-attribute

Whether or not to warn when experimental Prefect work pools are used.

PREFECT_EXPERIMENTAL_ENABLE_WORKERS = Setting(bool, default=True) module-attribute

Whether or not to enable experimental Prefect workers.

PREFECT_EXPERIMENTAL_WARN_WORKERS = Setting(bool, default=False) module-attribute

Whether or not to warn when experimental Prefect workers are used.

PREFECT_EXPERIMENTAL_WARN_VISUALIZE = Setting(bool, default=False) module-attribute

Whether or not to warn when experimental Prefect visualize is used.

PREFECT_EXPERIMENTAL_ENABLE_ENHANCED_CANCELLATION = Setting(bool, default=True) module-attribute

Whether or not to enable experimental enhanced flow run cancellation.

PREFECT_EXPERIMENTAL_WARN_ENHANCED_CANCELLATION = Setting(bool, default=False) module-attribute

Whether or not to warn when experimental enhanced flow run cancellation is used.

PREFECT_EXPERIMENTAL_ENABLE_DEPLOYMENT_STATUS = Setting(bool, default=True) module-attribute

Whether or not to enable deployment status in the UI

PREFECT_EXPERIMENTAL_WARN_DEPLOYMENT_STATUS = Setting(bool, default=False) module-attribute

Whether or not to warn when deployment status is used.

PREFECT_EXPERIMENTAL_FLOW_RUN_INPUT = Setting(bool, default=False) module-attribute

Whether or not to enable flow run input.

PREFECT_EXPERIMENTAL_WARN_FLOW_RUN_INPUT = Setting(bool, default=True) module-attribute

Whether or not to enable flow run input.

PREFECT_EXPERIMENTAL_EVENTS = Setting(bool, default=False) module-attribute

Whether to enable Prefect's server-side event features. Note that Prefect Cloud clients will always emit events during flow and task runs regardless of this setting.

PREFECT_RUNNER_PROCESS_LIMIT = Setting(int, default=5) module-attribute

Maximum number of processes a runner will execute in parallel.

PREFECT_RUNNER_POLL_FREQUENCY = Setting(int, default=10) module-attribute

Number of seconds a runner should wait between queries for scheduled work.

PREFECT_RUNNER_SERVER_MISSED_POLLS_TOLERANCE = Setting(int, default=2) module-attribute

Number of missed polls before a runner is considered unhealthy by its webserver.

PREFECT_RUNNER_SERVER_HOST = Setting(str, default='localhost') module-attribute

The host address the runner's webserver should bind to.

PREFECT_RUNNER_SERVER_PORT = Setting(int, default=8080) module-attribute

The port the runner's webserver should bind to.

PREFECT_RUNNER_SERVER_LOG_LEVEL = Setting(str, default='error') module-attribute

The log level of the runner's webserver.

PREFECT_RUNNER_SERVER_ENABLE = Setting(bool, default=False) module-attribute

Whether or not to enable the runner's webserver.

PREFECT_DEPLOYMENT_SCHEDULE_MAX_SCHEDULED_RUNS = Setting(int, default=50) module-attribute

The maximum number of scheduled runs to create for a deployment.

PREFECT_WORKER_HEARTBEAT_SECONDS = Setting(float, default=30) module-attribute

Number of seconds a worker should wait between sending a heartbeat.

PREFECT_WORKER_QUERY_SECONDS = Setting(float, default=10) module-attribute

Number of seconds a worker should wait between queries for scheduled flow runs.

PREFECT_WORKER_PREFETCH_SECONDS = Setting(float, default=10) module-attribute

The number of seconds into the future a worker should query for scheduled flow runs. Can be used to compensate for infrastructure start up time for a worker.

PREFECT_WORKER_WEBSERVER_HOST = Setting(str, default='0.0.0.0') module-attribute

The host address the worker's webserver should bind to.

PREFECT_WORKER_WEBSERVER_PORT = Setting(int, default=8080) module-attribute

The port the worker's webserver should bind to.

PREFECT_TASK_SCHEDULING_DEFAULT_STORAGE_BLOCK = Setting(str, default='local-file-system/prefect-task-scheduling') module-attribute

The block-type/block-document slug of a block to use as the default storage for autonomous tasks.

PREFECT_TASK_SCHEDULING_DELETE_FAILED_SUBMISSIONS = Setting(bool, default=True) module-attribute

Whether or not to delete failed task submissions from the database.

PREFECT_TASK_SCHEDULING_MAX_SCHEDULED_QUEUE_SIZE = Setting(int, default=1000) module-attribute

The maximum number of scheduled tasks to queue for submission.

PREFECT_TASK_SCHEDULING_MAX_RETRY_QUEUE_SIZE = Setting(int, default=100) module-attribute

The maximum number of retries to queue for submission.

PREFECT_TASK_SCHEDULING_PENDING_TASK_TIMEOUT = Setting(timedelta, default=timedelta(seconds=30)) module-attribute

How long before a PENDING task are made available to another task server. In practice, a task server should move a task from PENDING to RUNNING very quickly, so runs stuck in PENDING for a while is a sign that the task server may have crashed.

PREFECT_EXPERIMENTAL_ENABLE_EXTRA_RUNNER_ENDPOINTS = Setting(bool, default=False) module-attribute

Whether or not to enable experimental worker webserver endpoints.

PREFECT_EXPERIMENTAL_ENABLE_ARTIFACTS = Setting(bool, default=True) module-attribute

Whether or not to enable experimental Prefect artifacts.

PREFECT_EXPERIMENTAL_WARN_ARTIFACTS = Setting(bool, default=False) module-attribute

Whether or not to warn when experimental Prefect artifacts are used.

PREFECT_EXPERIMENTAL_ENABLE_WORKSPACE_DASHBOARD = Setting(bool, default=True) module-attribute

Whether or not to enable the experimental workspace dashboard.

PREFECT_EXPERIMENTAL_WARN_WORKSPACE_DASHBOARD = Setting(bool, default=False) module-attribute

Whether or not to warn when the experimental workspace dashboard is enabled.

PREFECT_EXPERIMENTAL_ENABLE_TASK_SCHEDULING = Setting(bool, default=False) module-attribute

Whether or not to enable experimental task scheduling.

PREFECT_EXPERIMENTAL_ENABLE_WORK_QUEUE_STATUS = Setting(bool, default=True) module-attribute

Whether or not to enable experimental work queue status in-place of work queue health.

PREFECT_EXPERIMENTAL_ENABLE_NEW_ENGINE = Setting(bool, default=False) module-attribute

Whether or not to enable experimental new engine.

PREFECT_EXPERIMENTAL_DISABLE_SYNC_COMPAT = Setting(bool, default=False) module-attribute

Whether or not to disable the sync_compatible decorator utility.

PREFECT_DEFAULT_RESULT_STORAGE_BLOCK = Setting(str, default=None) module-attribute

The block-type/block-document slug of a block to use as the default result storage.

PREFECT_DEFAULT_WORK_POOL_NAME = Setting(str, default=None) module-attribute

The default work pool to deploy to.

PREFECT_DEFAULT_DOCKER_BUILD_NAMESPACE = Setting(str, default=None) module-attribute

The default Docker namespace to use when building images.

Can be either an organization/username or a registry URL with an organization/username.

PREFECT_UI_SERVE_BASE = Setting(str, default='/') module-attribute

The base URL path to serve the Prefect UI from.

Defaults to the root path.

PREFECT_UI_STATIC_DIRECTORY = Setting(str, default=None) module-attribute

The directory to serve static files from. This should be used when running into permissions issues when attempting to serve the UI from the default directory (for example when running in a Docker container)

PREFECT_MESSAGING_BROKER = Setting(str, default='prefect.server.utilities.messaging.memory') module-attribute

Which message broker implementation to use for the messaging system, should point to a module that exports a Publisher and Consumer class.

PREFECT_MESSAGING_CACHE = Setting(str, default='prefect.server.utilities.messaging.memory') module-attribute

Which cache implementation to use for the events system. Should point to a module that exports a Cache class.

PREFECT_EVENTS_MAXIMUM_LABELS_PER_RESOURCE = Setting(int, default=500) module-attribute

The maximum number of labels a resource may have.

The maximum number of related resources an Event may have.

PREFECT_EVENTS_MAXIMUM_SIZE_BYTES = Setting(int, default=1500000) module-attribute

The maximum size of an Event when serialized to JSON

PREFECT_API_SERVICES_EVENT_LOGGER_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the event debug logger service in the server application.

PREFECT_API_SERVICES_TRIGGERS_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the triggers service in the server application.

PREFECT_EVENTS_EXPIRED_BUCKET_BUFFER = Setting(timedelta, default=timedelta(seconds=60)) module-attribute

The amount of time to retain expired automation buckets

PREFECT_EVENTS_PROACTIVE_GRANULARITY = Setting(timedelta, default=timedelta(seconds=5)) module-attribute

How frequently proactive automations are evaluated

PREFECT_API_SERVICES_EVENT_PERSISTER_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to start the event persister service in the server application.

PREFECT_API_SERVICES_EVENT_PERSISTER_BATCH_SIZE = Setting(int, default=20, gt=0) module-attribute

The number of events the event persister will attempt to insert in one batch.

PREFECT_API_SERVICES_EVENT_PERSISTER_FLUSH_INTERVAL = Setting(float, default=5, gt=0.0) module-attribute

The maximum number of seconds between flushes of the event persister.

PREFECT_EVENTS_RETENTION_PERIOD = Setting(timedelta, default=timedelta(days=7)) module-attribute

The amount of time to retain events in the database.

PREFECT_API_EVENTS_STREAM_OUT_ENABLED = Setting(bool, default=True) module-attribute

Whether or not to allow streaming events out of via websockets.

How long to cache related resource data for emitting server-side vents

PREFECT_RUN_ON_COMPLETION_HOOKS_ON_CACHED = Setting(bool, default=False) module-attribute

Whether or not to run on_completion hooks on cached task runs.

Setting

Bases: Generic[T]

Setting definition type.

Source code in prefect/settings.py 
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class Setting(Generic[T]):
    """
    Setting definition type.
    """

    def __init__(
        self,
        type: Type[T],
        *,
        deprecated: bool = False,
        deprecated_start_date: Optional[str] = None,
        deprecated_end_date: Optional[str] = None,
        deprecated_help: str = "",
        deprecated_when_message: str = "",
        deprecated_when: Optional[Callable[[Any], bool]] = None,
        deprecated_renamed_to: Optional["Setting[T]"] = None,
        value_callback: Optional[Callable[["Settings", T], T]] = None,
        is_secret: bool = False,
        **kwargs: Any,
    ) -> None:
        self.field: fields.FieldInfo = Field(**kwargs)
        self.type = type
        self.value_callback = value_callback
        self._name = None
        self.is_secret = is_secret
        self.deprecated = deprecated
        self.deprecated_start_date = deprecated_start_date
        self.deprecated_end_date = deprecated_end_date
        self.deprecated_help = deprecated_help
        self.deprecated_when = deprecated_when or (lambda _: True)
        self.deprecated_when_message = deprecated_when_message
        self.deprecated_renamed_to = deprecated_renamed_to
        self.deprecated_renamed_from = None
        self.__doc__ = self.field.description

        # Validate the deprecation settings, will throw an error at setting definition
        # time if the developer has not configured it correctly
        if deprecated:
            generate_deprecation_message(
                name="...",  # setting names not populated until after init
                start_date=self.deprecated_start_date,
                end_date=self.deprecated_end_date,
                help=self.deprecated_help,
                when=self.deprecated_when_message,
            )

        if deprecated_renamed_to is not None:
            # Track the deprecation both ways
            deprecated_renamed_to.deprecated_renamed_from = self

    def value(self, bypass_callback: bool = False) -> T:
        """
        Get the current value of a setting.

        Example:
        ```python
        from prefect.settings import PREFECT_API_URL
        PREFECT_API_URL.value()
        ```
        """
        return self.value_from(get_current_settings(), bypass_callback=bypass_callback)

    def value_from(self, settings: "Settings", bypass_callback: bool = False) -> T:
        """
        Get the value of a setting from a settings object

        Example:
        ```python
        from prefect.settings import get_default_settings
        PREFECT_API_URL.value_from(get_default_settings())
        ```
        """
        value = settings.value_of(self, bypass_callback=bypass_callback)

        if not bypass_callback and self.deprecated and self.deprecated_when(value):
            # Check if this setting is deprecated and someone is accessing the value
            # via the old name
            warnings.warn(self.deprecated_message, DeprecationWarning, stacklevel=3)

            # If the the value is empty, return the new setting's value for compat
            if value is None and self.deprecated_renamed_to is not None:
                return self.deprecated_renamed_to.value_from(settings)

        if not bypass_callback and self.deprecated_renamed_from is not None:
            # Check if this setting is a rename of a deprecated setting and the
            # deprecated setting is set and should be used for compatibility
            deprecated_value = self.deprecated_renamed_from.value_from(
                settings, bypass_callback=True
            )
            if deprecated_value is not None:
                warnings.warn(
                    (
                        f"{self.deprecated_renamed_from.deprecated_message} Because"
                        f" {self.deprecated_renamed_from.name!r} is set it will be used"
                        f" instead of {self.name!r} for backwards compatibility."
                    ),
                    DeprecationWarning,
                    stacklevel=3,
                )
            return deprecated_value or value

        return value

    @property
    def name(self):
        if self._name:
            return self._name

        # Lookup the name on first access
        for name, val in tuple(globals().items()):
            if val == self:
                self._name = name
                return name

        raise ValueError("Setting not found in `prefect.settings` module.")

    @name.setter
    def name(self, value: str):
        self._name = value

    @property
    def deprecated_message(self):
        return generate_deprecation_message(
            name=f"Setting {self.name!r}",
            start_date=self.deprecated_start_date,
            end_date=self.deprecated_end_date,
            help=self.deprecated_help,
            when=self.deprecated_when_message,
        )

    def __repr__(self) -> str:
        return f"<{self.name}: {self.type.__name__}>"

    def __bool__(self) -> bool:
        """
        Returns a truthy check of the current value.
        """
        return bool(self.value())

    def __eq__(self, __o: object) -> bool:
        return __o.__eq__(self.value())

    def __hash__(self) -> int:
        return hash((type(self), self.name))

value

Get the current value of a setting.

Example: 

from prefect.settings import PREFECT_API_URL
PREFECT_API_URL.value()

Source code in prefect/settings.py 
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def value(self, bypass_callback: bool = False) -> T:
    """
    Get the current value of a setting.

    Example:
    ```python
    from prefect.settings import PREFECT_API_URL
    PREFECT_API_URL.value()
    ```
    """
    return self.value_from(get_current_settings(), bypass_callback=bypass_callback)

value_from

Get the value of a setting from a settings object

Example: 

from prefect.settings import get_default_settings
PREFECT_API_URL.value_from(get_default_settings())

Source code in prefect/settings.py 
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def value_from(self, settings: "Settings", bypass_callback: bool = False) -> T:
    """
    Get the value of a setting from a settings object

    Example:
    ```python
    from prefect.settings import get_default_settings
    PREFECT_API_URL.value_from(get_default_settings())
    ```
    """
    value = settings.value_of(self, bypass_callback=bypass_callback)

    if not bypass_callback and self.deprecated and self.deprecated_when(value):
        # Check if this setting is deprecated and someone is accessing the value
        # via the old name
        warnings.warn(self.deprecated_message, DeprecationWarning, stacklevel=3)

        # If the the value is empty, return the new setting's value for compat
        if value is None and self.deprecated_renamed_to is not None:
            return self.deprecated_renamed_to.value_from(settings)

    if not bypass_callback and self.deprecated_renamed_from is not None:
        # Check if this setting is a rename of a deprecated setting and the
        # deprecated setting is set and should be used for compatibility
        deprecated_value = self.deprecated_renamed_from.value_from(
            settings, bypass_callback=True
        )
        if deprecated_value is not None:
            warnings.warn(
                (
                    f"{self.deprecated_renamed_from.deprecated_message} Because"
                    f" {self.deprecated_renamed_from.name!r} is set it will be used"
                    f" instead of {self.name!r} for backwards compatibility."
                ),
                DeprecationWarning,
                stacklevel=3,
            )
        return deprecated_value or value

    return value

Settings

Bases: SettingsFieldsMixin

Contains validated Prefect settings.

Settings should be accessed using the relevant Setting object. For example: 

from prefect.settings import PREFECT_HOME
PREFECT_HOME.value()

Accessing a setting attribute directly will ignore any value_callback mutations. This is not recommended: 

from prefect.settings import Settings
Settings().PREFECT_PROFILES_PATH  # PosixPath('${PREFECT_HOME}/profiles.toml')

Source code in prefect/settings.py 
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@add_cloudpickle_reduction
class Settings(SettingsFieldsMixin):
    """
    Contains validated Prefect settings.

    Settings should be accessed using the relevant `Setting` object. For example:
    ```python
    from prefect.settings import PREFECT_HOME
    PREFECT_HOME.value()
    ```

    Accessing a setting attribute directly will ignore any `value_callback` mutations.
    This is not recommended:
    ```python
    from prefect.settings import Settings
    Settings().PREFECT_PROFILES_PATH  # PosixPath('${PREFECT_HOME}/profiles.toml')
    ```
    """

    def value_of(self, setting: Setting[T], bypass_callback: bool = False) -> T:
        """
        Retrieve a setting's value.
        """
        value = getattr(self, setting.name)
        if setting.value_callback and not bypass_callback:
            value = setting.value_callback(self, value)
        return value

    @validator(PREFECT_LOGGING_LEVEL.name, PREFECT_LOGGING_SERVER_LEVEL.name)
    def check_valid_log_level(cls, value):
        if isinstance(value, str):
            value = value.upper()
        logging._checkLevel(value)
        return value

    @root_validator
    def post_root_validators(cls, values):
        """
        Add root validation functions for settings here.
        """
        # TODO: We could probably register these dynamically but this is the simpler
        #       approach for now. We can explore more interesting validation features
        #       in the future.
        values = max_log_size_smaller_than_batch_size(values)
        values = warn_on_database_password_value_without_usage(values)
        if not values["PREFECT_SILENCE_API_URL_MISCONFIGURATION"]:
            values = warn_on_misconfigured_api_url(values)
        return values

    def copy_with_update(
        self,
        updates: Mapping[Setting, Any] = None,
        set_defaults: Mapping[Setting, Any] = None,
        restore_defaults: Iterable[Setting] = None,
    ) -> "Settings":
        """
        Create a new `Settings` object with validation.

        Arguments:
            updates: A mapping of settings to new values. Existing values for the
                given settings will be overridden.
            set_defaults: A mapping of settings to new default values. Existing values for
                the given settings will only be overridden if they were not set.
            restore_defaults: An iterable of settings to restore to their default values.

        Returns:
            A new `Settings` object.
        """
        updates = updates or {}
        set_defaults = set_defaults or {}
        restore_defaults = restore_defaults or set()
        restore_defaults_names = {setting.name for setting in restore_defaults}

        return self.__class__(
            **{
                **{setting.name: value for setting, value in set_defaults.items()},
                **self.dict(exclude_unset=True, exclude=restore_defaults_names),
                **{setting.name: value for setting, value in updates.items()},
            }
        )

    def with_obfuscated_secrets(self):
        """
        Returns a copy of this settings object with secret setting values obfuscated.
        """
        settings = self.copy(
            update={
                setting.name: obfuscate(self.value_of(setting))
                for setting in SETTING_VARIABLES.values()
                if setting.is_secret
                # Exclude deprecated settings with null values to avoid warnings
                and not (setting.deprecated and self.value_of(setting) is None)
            }
        )
        # Ensure that settings that have not been marked as "set" before are still so
        # after we have updated their value above
        settings.__fields_set__.intersection_update(self.__fields_set__)
        return settings

    def hash_key(self) -> str:
        """
        Return a hash key for the settings object.  This is needed since some
        settings may be unhashable.  An example is lists.
        """
        env_variables = self.to_environment_variables()
        return str(hash(tuple((key, value) for key, value in env_variables.items())))

    def to_environment_variables(
        self, include: Iterable[Setting] = None, exclude_unset: bool = False
    ) -> Dict[str, str]:
        """
        Convert the settings object to environment variables.

        Note that setting values will not be run through their `value_callback` allowing
        dynamic resolution to occur when loaded from the returned environment.

        Args:
            include_keys: An iterable of settings to include in the return value.
                If not set, all settings are used.
            exclude_unset: Only include settings that have been set (i.e. the value is
                not from the default). If set, unset keys will be dropped even if they
                are set in `include_keys`.

        Returns:
            A dictionary of settings with values cast to strings
        """
        include = set(include or SETTING_VARIABLES.values())

        if exclude_unset:
            set_keys = {
                # Collect all of the "set" keys and cast to `Setting` objects
                SETTING_VARIABLES[key]
                for key in self.dict(exclude_unset=True)
            }
            include.intersection_update(set_keys)

        # Validate the types of items in `include` to prevent exclusion bugs
        for key in include:
            if not isinstance(key, Setting):
                raise TypeError(
                    "Invalid type {type(key).__name__!r} for key in `include`."
                )

        env = {
            # Use `getattr` instead of `value_of` to avoid value callback resolution
            key: getattr(self, key)
            for key, setting in SETTING_VARIABLES.items()
            if setting in include
        }

        # Cast to strings and drop null values
        return {key: str(value) for key, value in env.items() if value is not None}

    class Config:
        frozen = True

value_of

Retrieve a setting's value.

Source code in prefect/settings.py 
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def value_of(self, setting: Setting[T], bypass_callback: bool = False) -> T:
    """
    Retrieve a setting's value.
    """
    value = getattr(self, setting.name)
    if setting.value_callback and not bypass_callback:
        value = setting.value_callback(self, value)
    return value

post_root_validators

Add root validation functions for settings here.

Source code in prefect/settings.py 
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@root_validator
def post_root_validators(cls, values):
    """
    Add root validation functions for settings here.
    """
    # TODO: We could probably register these dynamically but this is the simpler
    #       approach for now. We can explore more interesting validation features
    #       in the future.
    values = max_log_size_smaller_than_batch_size(values)
    values = warn_on_database_password_value_without_usage(values)
    if not values["PREFECT_SILENCE_API_URL_MISCONFIGURATION"]:
        values = warn_on_misconfigured_api_url(values)
    return values

with_obfuscated_secrets

Returns a copy of this settings object with secret setting values obfuscated.

Source code in prefect/settings.py 
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def with_obfuscated_secrets(self):
    """
    Returns a copy of this settings object with secret setting values obfuscated.
    """
    settings = self.copy(
        update={
            setting.name: obfuscate(self.value_of(setting))
            for setting in SETTING_VARIABLES.values()
            if setting.is_secret
            # Exclude deprecated settings with null values to avoid warnings
            and not (setting.deprecated and self.value_of(setting) is None)
        }
    )
    # Ensure that settings that have not been marked as "set" before are still so
    # after we have updated their value above
    settings.__fields_set__.intersection_update(self.__fields_set__)
    return settings

hash_key

Return a hash key for the settings object. This is needed since some settings may be unhashable. An example is lists.

Source code in prefect/settings.py 
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def hash_key(self) -> str:
    """
    Return a hash key for the settings object.  This is needed since some
    settings may be unhashable.  An example is lists.
    """
    env_variables = self.to_environment_variables()
    return str(hash(tuple((key, value) for key, value in env_variables.items())))

to_environment_variables

Convert the settings object to environment variables.

Note that setting values will not be run through their value_callback allowing dynamic resolution to occur when loaded from the returned environment.

Parameters:

Name Type Description Default
include_keys

An iterable of settings to include in the return value. If not set, all settings are used.

 required
exclude_unset bool

Only include settings that have been set (i.e. the value is not from the default). If set, unset keys will be dropped even if they are set in include_keys.

 False

Returns:

Type Description
Dict[str, str]

A dictionary of settings with values cast to strings
Source code in prefect/settings.py 
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def to_environment_variables(
    self, include: Iterable[Setting] = None, exclude_unset: bool = False
) -> Dict[str, str]:
    """
    Convert the settings object to environment variables.

    Note that setting values will not be run through their `value_callback` allowing
    dynamic resolution to occur when loaded from the returned environment.

    Args:
        include_keys: An iterable of settings to include in the return value.
            If not set, all settings are used.
        exclude_unset: Only include settings that have been set (i.e. the value is
            not from the default). If set, unset keys will be dropped even if they
            are set in `include_keys`.

    Returns:
        A dictionary of settings with values cast to strings
    """
    include = set(include or SETTING_VARIABLES.values())

    if exclude_unset:
        set_keys = {
            # Collect all of the "set" keys and cast to `Setting` objects
            SETTING_VARIABLES[key]
            for key in self.dict(exclude_unset=True)
        }
        include.intersection_update(set_keys)

    # Validate the types of items in `include` to prevent exclusion bugs
    for key in include:
        if not isinstance(key, Setting):
            raise TypeError(
                "Invalid type {type(key).__name__!r} for key in `include`."
            )

    env = {
        # Use `getattr` instead of `value_of` to avoid value callback resolution
        key: getattr(self, key)
        for key, setting in SETTING_VARIABLES.items()
        if setting in include
    }

    # Cast to strings and drop null values
    return {key: str(value) for key, value in env.items() if value is not None}

Profile

Bases: BaseModel

A user profile containing settings.

Source code in prefect/settings.py 
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class Profile(BaseModel):
    """
    A user profile containing settings.
    """

    name: str
    settings: Dict[Setting, Any] = Field(default_factory=dict)
    source: Optional[Path]

    @validator("settings", pre=True)
    def map_names_to_settings(cls, value):
        return validate_settings(value)

    def validate_settings(self) -> None:
        """
        Validate the settings contained in this profile.

        Raises:
            pydantic.ValidationError: When settings do not have valid values.
        """
        # Create a new `Settings` instance with the settings from this profile relying
        # on Pydantic validation to raise an error.
        # We do not return the `Settings` object because this is not the recommended
        # path for constructing settings with a profile. See `use_profile` instead.
        Settings(**{setting.name: value for setting, value in self.settings.items()})

    def convert_deprecated_renamed_settings(self) -> List[Tuple[Setting, Setting]]:
        """
        Update settings in place to replace deprecated settings with new settings when
        renamed.

        Returns a list of tuples with the old and new setting.
        """
        changed = []
        for setting in tuple(self.settings):
            if (
                setting.deprecated
                and setting.deprecated_renamed_to
                and setting.deprecated_renamed_to not in self.settings
            ):
                self.settings[setting.deprecated_renamed_to] = self.settings.pop(
                    setting
                )
                changed.append((setting, setting.deprecated_renamed_to))
        return changed

    class Config:
        arbitrary_types_allowed = True

validate_settings

Validate the settings contained in this profile.

Raises:

Type Description
ValidationError

When settings do not have valid values.
Source code in prefect/settings.py 
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def validate_settings(self) -> None:
    """
    Validate the settings contained in this profile.

    Raises:
        pydantic.ValidationError: When settings do not have valid values.
    """
    # Create a new `Settings` instance with the settings from this profile relying
    # on Pydantic validation to raise an error.
    # We do not return the `Settings` object because this is not the recommended
    # path for constructing settings with a profile. See `use_profile` instead.
    Settings(**{setting.name: value for setting, value in self.settings.items()})

convert_deprecated_renamed_settings

Update settings in place to replace deprecated settings with new settings when renamed.

Returns a list of tuples with the old and new setting.

Source code in prefect/settings.py 
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def convert_deprecated_renamed_settings(self) -> List[Tuple[Setting, Setting]]:
    """
    Update settings in place to replace deprecated settings with new settings when
    renamed.

    Returns a list of tuples with the old and new setting.
    """
    changed = []
    for setting in tuple(self.settings):
        if (
            setting.deprecated
            and setting.deprecated_renamed_to
            and setting.deprecated_renamed_to not in self.settings
        ):
            self.settings[setting.deprecated_renamed_to] = self.settings.pop(
                setting
            )
            changed.append((setting, setting.deprecated_renamed_to))
    return changed

ProfilesCollection

" A utility class for working with a collection of profiles.

Profiles in the collection must have unique names.

The collection may store the name of the active profile.

Source code in prefect/settings.py 
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class ProfilesCollection:
    """ "
    A utility class for working with a collection of profiles.

    Profiles in the collection must have unique names.

    The collection may store the name of the active profile.
    """

    def __init__(
        self, profiles: Iterable[Profile], active: Optional[str] = None
    ) -> None:
        self.profiles_by_name = {profile.name: profile for profile in profiles}
        self.active_name = active

    @property
    def names(self) -> Set[str]:
        """
        Return a set of profile names in this collection.
        """
        return set(self.profiles_by_name.keys())

    @property
    def active_profile(self) -> Optional[Profile]:
        """
        Retrieve the active profile in this collection.
        """
        if self.active_name is None:
            return None
        return self[self.active_name]

    def set_active(self, name: Optional[str], check: bool = True):
        """
        Set the active profile name in the collection.

        A null value may be passed to indicate that this collection does not determine
        the active profile.
        """
        if check and name is not None and name not in self.names:
            raise ValueError(f"Unknown profile name {name!r}.")
        self.active_name = name

    def update_profile(
        self, name: str, settings: Mapping[Union[Dict, str], Any], source: Path = None
    ) -> Profile:
        """
        Add a profile to the collection or update the existing on if the name is already
        present in this collection.

        If updating an existing profile, the settings will be merged. Settings can
        be dropped from the existing profile by setting them to `None` in the new
        profile.

        Returns the new profile object.
        """
        existing = self.profiles_by_name.get(name)

        # Convert the input to a `Profile` to cast settings to the correct type
        profile = Profile(name=name, settings=settings, source=source)

        if existing:
            new_settings = {**existing.settings, **profile.settings}

            # Drop null keys to restore to default
            for key, value in tuple(new_settings.items()):
                if value is None:
                    new_settings.pop(key)

            new_profile = Profile(
                name=profile.name,
                settings=new_settings,
                source=source or profile.source,
            )
        else:
            new_profile = profile

        self.profiles_by_name[new_profile.name] = new_profile

        return new_profile

    def add_profile(self, profile: Profile) -> None:
        """
        Add a profile to the collection.

        If the profile name already exists, an exception will be raised.
        """
        if profile.name in self.profiles_by_name:
            raise ValueError(
                f"Profile name {profile.name!r} already exists in collection."
            )

        self.profiles_by_name[profile.name] = profile

    def remove_profile(self, name: str) -> None:
        """
        Remove a profile from the collection.
        """
        self.profiles_by_name.pop(name)

    def without_profile_source(self, path: Optional[Path]) -> "ProfilesCollection":
        """
        Remove profiles that were loaded from a given path.

        Returns a new collection.
        """
        return ProfilesCollection(
            [
                profile
                for profile in self.profiles_by_name.values()
                if profile.source != path
            ],
            active=self.active_name,
        )

    def to_dict(self):
        """
        Convert to a dictionary suitable for writing to disk.
        """
        return {
            "active": self.active_name,
            "profiles": {
                profile.name: {
                    setting.name: value for setting, value in profile.settings.items()
                }
                for profile in self.profiles_by_name.values()
            },
        }

    def __getitem__(self, name: str) -> Profile:
        return self.profiles_by_name[name]

    def __iter__(self):
        return self.profiles_by_name.__iter__()

    def items(self):
        return self.profiles_by_name.items()

    def __eq__(self, __o: object) -> bool:
        if not isinstance(__o, ProfilesCollection):
            return False

        return (
            self.profiles_by_name == __o.profiles_by_name
            and self.active_name == __o.active_name
        )

    def __repr__(self) -> str:
        return (
            f"ProfilesCollection(profiles={list(self.profiles_by_name.values())!r},"
            f" active={self.active_name!r})>"
        )

names: Set[str] property

Return a set of profile names in this collection.

active_profile: Optional[Profile] property

Retrieve the active profile in this collection.

set_active

Set the active profile name in the collection.

A null value may be passed to indicate that this collection does not determine the active profile.

Source code in prefect/settings.py 
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def set_active(self, name: Optional[str], check: bool = True):
    """
    Set the active profile name in the collection.

    A null value may be passed to indicate that this collection does not determine
    the active profile.
    """
    if check and name is not None and name not in self.names:
        raise ValueError(f"Unknown profile name {name!r}.")
    self.active_name = name

update_profile

Add a profile to the collection or update the existing on if the name is already present in this collection.

If updating an existing profile, the settings will be merged. Settings can be dropped from the existing profile by setting them to None in the new profile.

Returns the new profile object.

Source code in prefect/settings.py 
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def update_profile(
    self, name: str, settings: Mapping[Union[Dict, str], Any], source: Path = None
) -> Profile:
    """
    Add a profile to the collection or update the existing on if the name is already
    present in this collection.

    If updating an existing profile, the settings will be merged. Settings can
    be dropped from the existing profile by setting them to `None` in the new
    profile.

    Returns the new profile object.
    """
    existing = self.profiles_by_name.get(name)

    # Convert the input to a `Profile` to cast settings to the correct type
    profile = Profile(name=name, settings=settings, source=source)

    if existing:
        new_settings = {**existing.settings, **profile.settings}

        # Drop null keys to restore to default
        for key, value in tuple(new_settings.items()):
            if value is None:
                new_settings.pop(key)

        new_profile = Profile(
            name=profile.name,
            settings=new_settings,
            source=source or profile.source,
        )
    else:
        new_profile = profile

    self.profiles_by_name[new_profile.name] = new_profile

    return new_profile

add_profile

Add a profile to the collection.

If the profile name already exists, an exception will be raised.

Source code in prefect/settings.py 
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def add_profile(self, profile: Profile) -> None:
    """
    Add a profile to the collection.

    If the profile name already exists, an exception will be raised.
    """
    if profile.name in self.profiles_by_name:
        raise ValueError(
            f"Profile name {profile.name!r} already exists in collection."
        )

    self.profiles_by_name[profile.name] = profile

remove_profile

Remove a profile from the collection.

Source code in prefect/settings.py 
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def remove_profile(self, name: str) -> None:
    """
    Remove a profile from the collection.
    """
    self.profiles_by_name.pop(name)

without_profile_source

Remove profiles that were loaded from a given path.

Returns a new collection.

Source code in prefect/settings.py 
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def without_profile_source(self, path: Optional[Path]) -> "ProfilesCollection":
    """
    Remove profiles that were loaded from a given path.

    Returns a new collection.
    """
    return ProfilesCollection(
        [
            profile
            for profile in self.profiles_by_name.values()
            if profile.source != path
        ],
        active=self.active_name,
    )

get_extra_loggers

value_callback for PREFECT_LOGGING_EXTRA_LOGGERSthat parses the CSV string into a list and trims whitespace from logger names.

Source code in prefect/settings.py 
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def get_extra_loggers(_: "Settings", value: str) -> List[str]:
    """
    `value_callback` for `PREFECT_LOGGING_EXTRA_LOGGERS`that parses the CSV string into a
    list and trims whitespace from logger names.
    """
    return [name.strip() for name in value.split(",")] if value else []

debug_mode_log_level

value_callback for PREFECT_LOGGING_LEVEL that overrides the log level to DEBUG when debug mode is enabled.

Source code in prefect/settings.py 
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def debug_mode_log_level(settings, value):
    """
    `value_callback` for `PREFECT_LOGGING_LEVEL` that overrides the log level to DEBUG
    when debug mode is enabled.
    """
    if PREFECT_DEBUG_MODE.value_from(settings):
        return "DEBUG"
    else:
        return value

only_return_value_in_test_mode

value_callback for PREFECT_TEST_SETTING that only allows access during test mode

Source code in prefect/settings.py 
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def only_return_value_in_test_mode(settings, value):
    """
    `value_callback` for `PREFECT_TEST_SETTING` that only allows access during test mode
    """
    if PREFECT_TEST_MODE.value_from(settings):
        return value
    else:
        return None

default_ui_api_url

value_callback for PREFECT_UI_API_URL that sets the default value to relative path '/api', otherwise it constructs an API URL from the API settings.

Source code in prefect/settings.py 
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def default_ui_api_url(settings, value):
    """
    `value_callback` for `PREFECT_UI_API_URL` that sets the default value to
    relative path '/api', otherwise it constructs an API URL from the API settings.
    """
    if value is None:
        # Set a default value
        value = "/api"

    return template_with_settings(
        PREFECT_SERVER_API_HOST, PREFECT_SERVER_API_PORT, PREFECT_API_URL
    )(settings, value)

status_codes_as_integers_in_range

value_callback for PREFECT_CLIENT_RETRY_EXTRA_CODES that ensures status codes are integers in the range 100-599.

Source code in prefect/settings.py 
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def status_codes_as_integers_in_range(_, value):
    """
    `value_callback` for `PREFECT_CLIENT_RETRY_EXTRA_CODES` that ensures status codes
    are integers in the range 100-599.
    """
    if value == "":
        return set()

    values = {v.strip() for v in value.split(",")}

    if any(not v.isdigit() or int(v) < 100 or int(v) > 599 for v in values):
        raise ValueError(
            "PREFECT_CLIENT_RETRY_EXTRA_CODES must be a comma separated list of "
            "integers between 100 and 599."
        )

    values = {int(v) for v in values}
    return values

template_with_settings

Returns a value_callback that will template the given settings into the runtime value for the setting.

Source code in prefect/settings.py 
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def template_with_settings(*upstream_settings: Setting) -> Callable[["Settings", T], T]:
    """
    Returns a `value_callback` that will template the given settings into the runtime
    value for the setting.
    """

    def templater(settings, value):
        if value is None:
            return value  # Do not attempt to template a null string

        original_type = type(value)
        template_values = {
            setting.name: setting.value_from(settings) for setting in upstream_settings
        }
        template = string.Template(str(value))
        # Note the use of `safe_substitute` to avoid raising an exception if a
        # template value is missing. In this case, template values will be left
        # as-is in the string. Using `safe_substitute` prevents us raising when
        # the DB password contains a `$` character.
        return original_type(template.safe_substitute(template_values))

    return templater

max_log_size_smaller_than_batch_size

Validator for settings asserting the batch size and match log size are compatible

Source code in prefect/settings.py 
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def max_log_size_smaller_than_batch_size(values):
    """
    Validator for settings asserting the batch size and match log size are compatible
    """
    if (
        values["PREFECT_LOGGING_TO_API_BATCH_SIZE"]
        < values["PREFECT_LOGGING_TO_API_MAX_LOG_SIZE"]
    ):
        raise ValueError(
            "`PREFECT_LOGGING_TO_API_MAX_LOG_SIZE` cannot be larger than"
            " `PREFECT_LOGGING_TO_API_BATCH_SIZE`"
        )
    return values

warn_on_database_password_value_without_usage

Validator for settings warning if the database password is set but not used.

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def warn_on_database_password_value_without_usage(values):
    """
    Validator for settings warning if the database password is set but not used.
    """
    value = values["PREFECT_API_DATABASE_PASSWORD"]
    if (
        value
        and not value.startswith(OBFUSCATED_PREFIX)
        and (
            "PREFECT_API_DATABASE_PASSWORD"
            not in values["PREFECT_API_DATABASE_CONNECTION_URL"]
        )
    ):
        warnings.warn(
            "PREFECT_API_DATABASE_PASSWORD is set but not included in the "
            "PREFECT_API_DATABASE_CONNECTION_URL. "
            "The provided password will be ignored."
        )
    return values

warn_on_misconfigured_api_url

Validator for settings warning if the API URL is misconfigured.

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def warn_on_misconfigured_api_url(values):
    """
    Validator for settings warning if the API URL is misconfigured.
    """
    api_url = values["PREFECT_API_URL"]
    if api_url is not None:
        misconfigured_mappings = {
            "app.prefect.cloud": (
                "`PREFECT_API_URL` points to `app.prefect.cloud`. Did you"
                " mean `api.prefect.cloud`?"
            ),
            "account/": (
                "`PREFECT_API_URL` uses `/account/` but should use `/accounts/`."
            ),
            "workspace/": (
                "`PREFECT_API_URL` uses `/workspace/` but should use `/workspaces/`."
            ),
        }
        warnings_list = []

        for misconfig, warning in misconfigured_mappings.items():
            if misconfig in api_url:
                warnings_list.append(warning)

        parsed_url = urlparse(api_url)
        if parsed_url.path and not parsed_url.path.startswith("/api"):
            warnings_list.append(
                "`PREFECT_API_URL` should have `/api` after the base URL."
            )

        if warnings_list:
            example = 'e.g. PREFECT_API_URL="https://api.prefect.cloud/api/accounts/[ACCOUNT-ID]/workspaces/[WORKSPACE-ID]"'
            warnings_list.append(example)

            warnings.warn("\n".join(warnings_list), stacklevel=2)

    return values

automation_settings_enabled

Whether or not automations are enabled.

Source code in prefect/settings.py 
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def automation_settings_enabled() -> bool:
    """
    Whether or not automations are enabled.
    """
    return (
        PREFECT_EXPERIMENTAL_EVENTS.value()
        and PREFECT_API_SERVICES_TRIGGERS_ENABLED.value()
    )

get_current_settings

Returns a settings object populated with values from the current settings context or, if no settings context is active, the environment.

Source code in prefect/settings.py 
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def get_current_settings() -> Settings:
    """
    Returns a settings object populated with values from the current settings context
    or, if no settings context is active, the environment.
    """
    from prefect.context import SettingsContext

    settings_context = SettingsContext.get()
    if settings_context is not None:
        return settings_context.settings

    return get_settings_from_env()

get_settings_from_env

Returns a settings object populated with default values and overrides from environment variables, ignoring any values in profiles.

Calls with the same environment return a cached object instead of reconstructing to avoid validation overhead.

Source code in prefect/settings.py 
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def get_settings_from_env() -> Settings:
    """
    Returns a settings object populated with default values and overrides from
    environment variables, ignoring any values in profiles.

    Calls with the same environment return a cached object instead of reconstructing
    to avoid validation overhead.
    """
    # Since os.environ is a Dict[str, str] we can safely hash it by contents, but we
    # must be careful to avoid hashing a generator instead of a tuple
    cache_key = hash(tuple((key, value) for key, value in os.environ.items()))

    if cache_key not in _FROM_ENV_CACHE:
        _FROM_ENV_CACHE[cache_key] = Settings()

    return _FROM_ENV_CACHE[cache_key]

get_default_settings

Returns a settings object populated with default values, ignoring any overrides from environment variables or profiles.

This is cached since the defaults should not change during the lifetime of the module.

Source code in prefect/settings.py 
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def get_default_settings() -> Settings:
    """
    Returns a settings object populated with default values, ignoring any overrides
    from environment variables or profiles.

    This is cached since the defaults should not change during the lifetime of the
    module.
    """
    global _DEFAULTS_CACHE

    if not _DEFAULTS_CACHE:
        old = os.environ
        try:
            os.environ = {}
            settings = get_settings_from_env()
        finally:
            os.environ = old

        _DEFAULTS_CACHE = settings

    return _DEFAULTS_CACHE

temporary_settings

Temporarily override the current settings by entering a new profile.

See Settings.copy_with_update for details on different argument behavior.

Examples:

>>> from prefect.settings import PREFECT_API_URL
>>>
>>> with temporary_settings(updates={PREFECT_API_URL: "foo"}):
>>>    assert PREFECT_API_URL.value() == "foo"
>>>
>>>    with temporary_settings(set_defaults={PREFECT_API_URL: "bar"}):
>>>         assert PREFECT_API_URL.value() == "foo"
>>>
>>>    with temporary_settings(restore_defaults={PREFECT_API_URL}):
>>>         assert PREFECT_API_URL.value() is None
>>>
>>>         with temporary_settings(set_defaults={PREFECT_API_URL: "bar"})
>>>             assert PREFECT_API_URL.value() == "bar"
>>> assert PREFECT_API_URL.value() is None
Source code in prefect/settings.py 
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@contextmanager
def temporary_settings(
    updates: Optional[Mapping[Setting[T], Any]] = None,
    set_defaults: Optional[Mapping[Setting[T], Any]] = None,
    restore_defaults: Optional[Iterable[Setting[T]]] = None,
) -> Generator[Settings, None, None]:
    """
    Temporarily override the current settings by entering a new profile.

    See `Settings.copy_with_update` for details on different argument behavior.

    Examples:
        >>> from prefect.settings import PREFECT_API_URL
        >>>
        >>> with temporary_settings(updates={PREFECT_API_URL: "foo"}):
        >>>    assert PREFECT_API_URL.value() == "foo"
        >>>
        >>>    with temporary_settings(set_defaults={PREFECT_API_URL: "bar"}):
        >>>         assert PREFECT_API_URL.value() == "foo"
        >>>
        >>>    with temporary_settings(restore_defaults={PREFECT_API_URL}):
        >>>         assert PREFECT_API_URL.value() is None
        >>>
        >>>         with temporary_settings(set_defaults={PREFECT_API_URL: "bar"})
        >>>             assert PREFECT_API_URL.value() == "bar"
        >>> assert PREFECT_API_URL.value() is None
    """
    import prefect.context

    context = prefect.context.get_settings_context()

    new_settings = context.settings.copy_with_update(
        updates=updates, set_defaults=set_defaults, restore_defaults=restore_defaults
    )

    with prefect.context.SettingsContext(
        profile=context.profile, settings=new_settings
    ):
        yield new_settings

load_profiles

Load all profiles from the default and current profile paths.

Source code in prefect/settings.py 
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def load_profiles() -> ProfilesCollection:
    """
    Load all profiles from the default and current profile paths.
    """
    profiles = _read_profiles_from(DEFAULT_PROFILES_PATH)

    user_profiles_path = PREFECT_PROFILES_PATH.value()
    if user_profiles_path.exists():
        user_profiles = _read_profiles_from(user_profiles_path)

        # Merge all of the user profiles with the defaults
        for name in user_profiles:
            profiles.update_profile(
                name,
                settings=user_profiles[name].settings,
                source=user_profiles[name].source,
            )

        if user_profiles.active_name:
            profiles.set_active(user_profiles.active_name, check=False)

    return profiles

load_current_profile

Load the current profile from the default and current profile paths.

This will not include settings from the current settings context. Only settings that have been persisted to the profiles file will be saved.

Source code in prefect/settings.py 
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def load_current_profile():
    """
    Load the current profile from the default and current profile paths.

    This will _not_ include settings from the current settings context. Only settings
    that have been persisted to the profiles file will be saved.
    """
    from prefect.context import SettingsContext

    profiles = load_profiles()
    context = SettingsContext.get()

    if context:
        profiles.set_active(context.profile.name)

    return profiles.active_profile

save_profiles

Writes all non-default profiles to the current profiles path.

Source code in prefect/settings.py 
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def save_profiles(profiles: ProfilesCollection) -> None:
    """
    Writes all non-default profiles to the current profiles path.
    """
    profiles_path = PREFECT_PROFILES_PATH.value()
    profiles = profiles.without_profile_source(DEFAULT_PROFILES_PATH)
    return _write_profiles_to(profiles_path, profiles)

load_profile

Load a single profile by name.

Source code in prefect/settings.py 
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def load_profile(name: str) -> Profile:
    """
    Load a single profile by name.
    """
    profiles = load_profiles()
    try:
        return profiles[name]
    except KeyError:
        raise ValueError(f"Profile {name!r} not found.")

update_current_profile

Update the persisted data for the profile currently in-use.

If the profile does not exist in the profiles file, it will be created.

Given settings will be merged with the existing settings as described in ProfilesCollection.update_profile.

Returns:

Type Description
Profile

The new profile.
Source code in prefect/settings.py 
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def update_current_profile(settings: Dict[Union[str, Setting], Any]) -> Profile:
    """
    Update the persisted data for the profile currently in-use.

    If the profile does not exist in the profiles file, it will be created.

    Given settings will be merged with the existing settings as described in
    `ProfilesCollection.update_profile`.

    Returns:
        The new profile.
    """
    import prefect.context

    current_profile = prefect.context.get_settings_context().profile

    if not current_profile:
        raise MissingProfileError("No profile is currently in use.")

    profiles = load_profiles()

    # Ensure the current profile's settings are present
    profiles.update_profile(current_profile.name, current_profile.settings)
    # Then merge the new settings in
    new_profile = profiles.update_profile(current_profile.name, settings)

    # Validate before saving
    new_profile.validate_settings()

    save_profiles(profiles)

    return profiles[current_profile.name]