​
prefect.server.api.server

Defines the Prefect REST API FastAPI app.

​
Functions

​
is_client_retryable_exception 

is_client_retryable_exception(exc: Exception) -> bool

​
replace_placeholder_string_in_files 

replace_placeholder_string_in_files(directory: str, placeholder: str, replacement: str, allowed_extensions: list[str] | None = None) -> None
Recursively loops through all files in the given directory and replaces a placeholder string.

​
copy_directory 

copy_directory(directory: str, path: str) -> None

​
create_api_app 

create_api_app(dependencies: list[Any] | None = None, health_check_path: str = '/health', version_check_path: str = '/version', fast_api_app_kwargs: dict[str, Any] | None = None, final: bool = False, ignore_cache: bool = False) -> FastAPI
Create a FastAPI app that includes the Prefect REST API Args:
  • dependencies: a list of global dependencies to add to each Prefect REST API router
  • health_check_path: the health check route path
  • fast_api_app_kwargs: kwargs to pass to the FastAPI constructor
  • final: whether this will be the last instance of the Prefect server to be created in this process, so that additional optimizations may be applied
  • ignore_cache: if set, a new app will be created even if the settings and fast_api_app_kwargs match an existing app in the cache
Returns:
  • a FastAPI app that serves the Prefect REST API

​
create_ui_app 

create_ui_app(ephemeral: bool) -> FastAPI

​
create_app 

create_app(settings: Optional[prefect.settings.Settings] = None, ephemeral: bool = False, webserver_only: bool = False, final: bool = False, ignore_cache: bool = False) -> FastAPI
Create a FastAPI app that includes the Prefect REST API and UI Args:
  • settings: The settings to use to create the app. If not set, settings are pulled from the context.
  • ephemeral: If set, the application will be treated as ephemeral. The UI and services will be disabled.
  • webserver_only: If set, the webserver and UI will be available but all background services will be disabled.
  • final: whether this will be the last instance of the Prefect server to be created in this process, so that additional optimizations may be applied
  • ignore_cache: If set, a new application will be created even if the settings match. Otherwise, an application is returned from the cache.

​
Classes

​
SPAStaticFiles

Implementation of StaticFiles for serving single page applications. Adds get_response handling to ensure that when a resource isn’t found the application still returns the index.

​
RequestLimitMiddleware

A middleware that limits the number of concurrent requests handled by the API. This is a blunt tool for limiting SQLite concurrent writes which will cause failures at high volume. Ideally, we would only apply the limit to routes that perform writes.

​
SubprocessASGIServer

Methods:

​
find_available_port 

find_available_port(self) -> int

​
is_port_available 

is_port_available(port: int) -> bool

​
address 

address(self) -> str

​
api_url 

api_url(self) -> str

​
start 

start(self, timeout: Optional[int] = None) -> None
Start the server in a separate process. Safe to call multiple times; only starts the server once. Args:
  • timeout: The maximum time to wait for the server to start

​
stop 

stop(self) -> None