Configuration¶

Basics¶

In Flask, the configuration system is built on top of the app.config attribute. It's a dict-like attribute; thus you can operate it as a dict.

This app.config attribute will contain the following configuration variables:

Flask's built-in configuration variables
Flask extension's built-in configuration variables
APIFlask's built-in configuration variables
Your application's configuration variables

Here is a simple example for basic operates:

from apiflask import APIFlask

app = APIFlask(__name__)

# set a config
app.config['DESCRIPTION'] = 'A wonderful API'

# read a config
description = app.config['DESCRIPTION']

Since it's dict-like object, you can also read a configuration variable with a default value via the app.config.get() method:

my_name = app.config.get('DESCRIPTION', 'default value')

Or update multiple values at once via app.config.update() method:

app.config.update(
    'DESCRIPTION'='A wonderful API',
    'FOO'='bar',
    'ITEMS_PER_PAGE'=15
)

For a large application, you can store all the configuration variable in a separate file, for example, a file called settings.py:

MY_CONFIG = 'A wonderful API'
FOO = 'bar'
ITEMS_PER_PAGE = 15

Now you can set the configuration variables with the app.config.from_pyfile() method:

from apiflask import APIFlask

app = APIFlask(__name__)

# set all configs from settings.py
app.config.from_pyfile('settings.py')

Read more about configuration management in Configuration Handling in Flask's documentation.

Warning

All configuration variables should be in uppercase.

Read a config outside of the application context

If you want to read a configuration variable outside of the application context, you will get an error like: "Working outside of the application context". This usually happened when you use an application factory.

When you use the application factory, you can access the config with current_app.config in the view function:

from flask import current_app

@bp.get('/foo')
def foo():
    bar = current_app.config['BAR']

However, when you define a data schema, there isn't an active application context, so you can't use current_app. In this situation, you can access the configration variables from the module you store them:

from apiflask import Schema

from .settings import CATEGORIES  # import the configuration variable

class PetIn(Schema):
    name = String(required=True, validate=Length(0, 10))
    category = String(required=True, validate=OneOf(CATEGORIES))  # use it

Below are all the built-in configuration variables in APIFlask.

OpenAPI fields¶

All the configurations of OpenAPI-related fields will be used when generating the OpenAPI spec. They will also be rendered by the API documentation.

OPENAPI_VERSION¶

The version of OpenAPI Specification (openapi.openapi). This configuration can also be configured from the app.openapi_version attribute.

Type: str
Default value: '3.0.3'
Examples:

app.config['OPENAPI_VERSION'] = '3.0.2'

Or:

app.openapi_version = '3.0.2'

Version >= 0.4.0

This configuration variable was added in the version 0.4.0.

SERVERS¶

The server information of the API (openapi.servers), accepts multiple server dicts. This configuration can also be configured from the app.servers attribute.

Type: List[Dict[str, str]]
Default value: None
Examples:

app.config['SERVERS'] = [
    {
        'name': 'Production Server',
        'url': 'http://api.example.com'
    }
]

Or:

app.servers = [
    {
        'name': 'Production Server',
        'url': 'http://api.example.com'
    }
]

TAGS¶

The tag list of the OpenAPI spec documentation (openapi.tags), accepts a list of dicts. You can also pass a simple list contains the tag name string. This configuration can also be configured from the app.tags attribute.

If not set, the blueprint names will use as tags, all the endpoints under the blueprint will be marked with the blueprint tag automatically.

Type: Union[List[str], List[Dict[str, str]]]
Default value: None
Examples:

Simple tag name list example:

app.config['TAGS'] = ['foo', 'bar', 'baz']

With tag description:

app.config['TAGS'] = [
    {'name': 'foo', 'description': 'The description of foo'},
    {'name': 'bar', 'description': 'The description of bar'},
    {'name': 'baz', 'description': 'The description of baz'}
]

Full OpenAPI tags example:

app.config['TAGS'] = [
    {
        'name': 'foo',
        'description': 'tag description',
        'externalDocs': {
            'description': 'Find more info here',
            'url': 'http://example.com'
        }
    }
]

Use attribute app.tags:

app.tags = ['foo', 'bar', 'baz']

EXTERNAL_DOCS¶

The external documentation information of the API (openapi.externalDocs). This configuration can also be configured from the app.external_docs attribute.

Type: Dict[str, str]
Default value: None
Examples:

app.config['EXTERNAL_DOCS'] = {
    'description': 'Find more info here',
    'url': 'http://docs.example.com'
}

Or:

app.external_docs = {
    'description': 'Find more info here',
    'url': 'http://docs.example.com'
}

INFO¶

The info field of the API (openapi.info). This configuration can also be configured from the app.info attribute. The info object (openapi.info), it accepts a dict contains following info fields: description, termsOfService, contact, license. You can use separate configuration variables to overwrite this dict.

Type: Dict[str, str]
Default value: None
Examples:

app.config['INFO'] = {
    'description': '...',
    'termsOfService': 'http://example.com',
    'contact': {
        'name': 'API Support',
        'url': 'http://www.example.com/support',
        'email': 'support@example.com'
    },
    'license': {
        'name': 'Apache 2.0',
        'url': 'http://www.apache.org/licenses/LICENSE-2.0.html'
    }
}

Or:

app.info = {
    'description': '...',
    'termsOfService': 'http://example.com',
    'contact': {
        'name': 'API Support',
        'url': 'http://www.example.com/support',
        'email': 'support@example.com'
    },
    'license': {
        'name': 'Apache 2.0',
        'url': 'http://www.apache.org/licenses/LICENSE-2.0.html'
    }
}

DESCRIPTION¶

The description of the API (openapi.info.description). This configuration can also be configured from the app.description attribute.

Type: str
Default value: None
Examples:

app.config['DESCRIPTION'] = 'Some description of my API.'

Or:

app.description = 'Some description of my API.'

TERMS_OF_SERVICE¶

The terms of service URL of the API (openapi.info.termsOfService). This configuration can also be configured from the app.terms_of_service attribute.

Type: str
Default value: None
Examples:

app.config['TERMS_OF_SERVICE'] = 'http://example.com/terms/'

Or:

app.terms_of_service = 'http://example.com/terms/'

CONTACT¶

The contact information of the API (openapi.info.contact). This configuration can also be configured from the app.contact attribute.

Type: Dict[str, str]
Default value: None
Examples:

app.config['CONTACT'] = {
    'name': 'API Support',
    'url': 'http://example.com',
    'email': 'support@example.com'
}

Or:

app.contact = {
    'name': 'API Support',
    'url': 'http://example.com',
    'email': 'support@example.com'
}

LICENSE¶

The license of the API (openapi.info.license). This configuration can also be configured from the app.license attribute.

Type: Dict[str, str]
Default value: None
Examples:

app.config['LICENSE'] = {
    'name': 'Apache 2.0',
    'url': 'http://www.apache.org/licenses/LICENSE-2.0.html'
}

Or:

app.license = {
    'name': 'Apache 2.0',
    'url': 'http://www.apache.org/licenses/LICENSE-2.0.html'
}

OpenAPI spec¶

Customize the generation of the OpenAPI spec.

SPEC_FORMAT¶

The format of the OpenAPI spec, accepts 'json', 'yaml' or 'yml'. This config will be used in the following conditions:

Serve the spec via the built-in route.
Execute flask spec without passing the --format/-f option.

Warning

The auto-detection of the format from the APIFlask(spec_path=...) was removed in favor of this config in 0.7.0.

Type: str
Default value: 'json'
Examples:

app.config['SPEC_FORMAT'] = 'yaml'

Version >= 0.7.0

This configuration variable was added in the version 0.7.0.

LOCAL_SPEC_PATH¶

The path to the local OpenAPI spec file.

Type: str
Default value: None
Examples:

app.config['LOCAL_SPEC_PATH'] = 'openapi.json'

Warning

If the path you passed is relative, do not put a leading slash in it.

Version >= 0.7.0

This configuration variable was added in the version 0.7.0.

LOCAL_SPEC_JSON_INDENT¶

The indentation of the local OpenAPI spec in JSON format.

Type: int
Default value: 2
Examples:

app.config['LOCAL_SPEC_JSON_INDENT'] = 4

Version >= 0.7.0

This configuration variable was added in the version 0.7.0.

SYNC_LOCAL_SPEC¶

If True, the local spec will be in sync automatically, see the example usage at Keep the local spec in sync automatically.

Type: bool
Default value: None
Examples:

app.config['SYNC_LOCAL_SPEC'] = True

Version >= 0.7.0

This configuration variable was added in the version 0.7.0.

JSON_SPEC_MIMETYPE¶

The MIME type string for JSON OpenAPI spec response.

Type: str
Default value: 'application/json'
Examples:

app.config['JSON_SPEC_MIMETYPE'] = 'application/custom-json'

Version >= 0.4.0

This configuration variable was added in the version 0.4.0.

YAML_SPEC_MIMETYPE¶

The MIME type string for YAML OpenAPI spec response.

Type: str
Default value: 'text/vnd.yaml'
Examples:

app.config['YAML_SPEC_MIMETYPE'] = 'text/x-yaml'

Version >= 0.4.0

This configuration variable was added in the version 0.4.0.

Automation behavior control¶

The following configuration variables are used to control the automation behavior of APIFlask. The default values of all these configuration variables are True, you can disable them if you needed.

AUTO_TAGS¶

Enable or disable auto tags (openapi.tags) generation from the name of the blueprint.

Tip

This automation behavior only happens when app.tags or config TAGS is not set.

Type: bool
Default value: True
Examples:

app.config['AUTO_TAGS'] = False

AUTO_OPERATION_SUMMARY¶

Enable or disable auto path summary from the name or docstring of the view function.

Tip

This automation behavior only happens when the view function doesn't decorate with @app.doc(summary=...).

Type: bool
Default value: True
Examples:

app.config['AUTO_OPERATION_SUMMARY'] = False

Warning

This variable was renamed from AUTO_PATH_SUMMARY to AUTO_OPERATION_SUMMARY since version 0.8.0.

AUTO_OPERATION_DESCRIPTION¶

Enable or disable auto path description from the docstring of the view function.

Tip

This automation behavior only happens when the view function doesn't decorate with @app.doc(description=...).

Type: bool
Default value: True
Examples:

app.config['AUTO_OPERATION_DESCRIPTION'] = False

Warning

This variable was renamed from AUTO_PATH_DESCRIPTION to AUTO_OPERATION_DESCRIPTION since version 0.8.0.

AUTO_OPERATION_ID¶

Version >= 0.10.0

This feature was added in the version 0.10.0.

Enable or disable auto operationId from the method and endpoint of the view function. See more details in Set operationId.

Type: bool
Default value: False
Examples:

app.config['AUTO_OPERATION_ID'] = True

AUTO_200_RESPONSE¶

If a view function doesn't decorate with either @app.input, @app.output, @app.auth_required or @app.doc, APIFlask will add a default 200 response for this view into OpenAPI spec. Set this config to False to disable this behavior.

Tip

You can change the description of the default 200 response with config SUCCESS_DESCRIPTION.

Type: bool
Default value: True
Examples:

app.config['AUTO_200_RESPONSE'] = False

`AUTO_404_RESPONSE`¶

If a view function's URL rule contains a variable. By default, APIFlask will add a 404 response for this view into OpenAPI spec. Set this config to False to disable this behavior.

Tip

You can change the description of the automatic 404 response with config NOT_FOUND_DESCRIPTION.

Type: bool
Default value: True
Examples:

app.config['AUTO_404_RESPONSE'] = False

Version >= 0.8.0

This configuration variable was added in the version 0.8.0.

AUTO_VALIDATION_ERROR_RESPONSE¶

If a view function uses @app.input to validate input request data, APIFlask will add a validation error response into OpenAPI spec for this view. Set this config to False to disable this behavior.

Type: bool
Default value: True
Examples:

app.config['AUTO_VALIDATION_ERROR_RESPONSE'] = False

AUTO_AUTH_ERROR_RESPONSE¶

If a view function uses @app.auth_required to restrict the access, APIFlask will add an authentication error response into OpenAPI spec for this view. Set this config to False to disable this behavior.

Type: bool
Default value: True
Examples:

app.config['AUTO_AUTH_ERROR_RESPONSE'] = False

Response customization¶

The following configuration variables are used to customize auto-responses.

SUCCESS_DESCRIPTION¶

The default OpenAPI description of the 2XX responses.

Type: str
Default value: Successful response
Examples:

app.config['SUCCESS_DESCRIPTION'] = 'Success!'

Version >= 0.4.0

This configuration variable was added in the version 0.4.0.

NOT_FOUND_DESCRIPTION¶

The default OpenAPI description of the 404 response.

Type: str
Default value: Not found
Examples:

app.config['NOT_FOUND_DESCRIPTION'] = 'Missing'

Version >= 0.8.0

This configuration variable was added in the version 0.8.0.

VALIDATION_ERROR_STATUS_CODE¶

The status code of validation error response.

Type: int
Default value: 400
Examples:

app.config['VALIDATION_ERROR_STATUS_CODE'] = 422

VALIDATION_ERROR_DESCRIPTION¶

The OpenAPI description of validation error response.

Type: str
Default value: 'Validation error'
Examples:

app.config['VALIDATION_ERROR_DESCRIPTION'] = 'Invalid JSON body'

VALIDATION_ERROR_SCHEMA¶

The schema of validation error response, accepts a schema class or a dict of OpenAPI schema definition.

Type: Union[Schema, dict]
Default value: apiflask.schemas.validation_error_schema
Examples:

app.config['VALIDATION_ERROR_SCHEMA'] = CustomValidationErrorSchema

AUTH_ERROR_STATUS_CODE¶

The status code of authentication error response.

Type: int
Default value: 401
Examples:

app.config['AUTH_ERROR_STATUS_CODE'] = 403

AUTH_ERROR_DESCRIPTION¶

The OpenAPI description of authentication error response.

Type: str
Default value: 'Authentication error'
Examples:

app.config['AUTH_ERROR_DESCRIPTION'] = 'Auth error'

HTTP_ERROR_SCHEMA¶

The schema of generic HTTP error response, accepts a schema class or a dict of OpenAPI schema definition.

Type: Union[Schema, dict]
Default value: apiflask.schemas.http_error_schema
Examples:

app.config['HTTP_ERROR_SCHEMA'] = CustomHTTPErrorSchema

BASE_RESPONSE_SCHEMA¶

The schema of base response schema, accepts a schema class or a dict of OpenAPI schema definition.

Type: Union[Schema, dict]
Default value: None
Examples:

from apiflask import APIFlask, Schema
from apiflask.fields import String, Integer, Field

app = APIFlask(__name__)

class BaseResponse(Schema):
    message = String()
    status_code = Integer()
    data = Field()

app.config['BASE_RESPONSE_SCHEMA'] = BaseResponse

Version >= 0.9.0

This configuration variable was added in the version 0.9.0.

BASE_RESPONSE_DATA_KEY¶

The data key of the base response, it should match the data field name in the base response schema.

Type: str
Default value: 'data'
Examples:

app.config['BASE_RESPONSE_DATA_KEY'] = 'data'

Version >= 0.9.0

This configuration variable was added in the version 0.9.0.

API documentation¶

The following configuration variables used to customize API documentation.

DOCS_FAVICON¶

The absolute or relative URL of the favicon image file of API documentations.

Type: str
Default value: 'https://apiflask.com/_assets/favicon.png'
Examples:

app.config['DOCS_FAVICON'] = 'https://cdn.example.com/favicon.png'

REDOC_USE_GOOGLE_FONT¶

Enable or disable Google font in Redoc documentation.

Type: bool
Default value: True
Examples:

app.config['REDOC_USE_GOOGLE_FONT'] = False

REDOC_CONFIG¶

The configuration options pass to Redoc. See the available options in the Redoc documentation.

Type: dict
Default value: None
Examples:

app.config['REDOC_CONFIG'] = {'disableSearch': True, 'hideLoading': True}

Version >= 0.9.0

This configuration variable was added in the version 0.9.0.

REDOC_STANDALONE_JS`¶

The absolute or relative URL of the Redoc standalone JavaScript file.

Type: str
Default value: 'https://cdn.jsdelivr.net/npm/redoc@next/bundles/redoc.standalone.js'
Examples:

app.config['REDOC_STANDALONE_JS'] = 'https://cdn.redoc.ly/redoc/latest/bundles/redoc.standalone.js'

SWAGGER_UI_CSS¶

The absolute or relative URL of the Swagger UI CSS file.

Type: str
Default value: 'https://cdn.jsdelivr.net/npm/swagger-ui-dist@3/swagger-ui.css'
Examples:

app.config['SWAGGER_UI_CSS'] = 'https://cdnjs.cloudflare.com/ajax/libs/swagger-ui/4.11.1/swagger-ui.min.css'

SWAGGER_UI_BUNDLE_JS¶

The absolute or relative URL of the Swagger UI bundle JavaScript file.

Type: str
Default value: 'https://cdn.jsdelivr.net/npm/swagger-ui-dist@3/swagger-ui-bundle.js'
Examples:

app.config['SWAGGER_UI_BUNDLE_JS'] = 'https://cdnjs.cloudflare.com/ajax/libs/swagger-ui/4.11.1/swagger-ui-bundle.min.js'

SWAGGER_UI_STANDALONE_PRESET_JS¶

The absolute or relative URL of the Swagger UI standalone preset JavaScript file.

Type: str
Default value: 'https://cdn.jsdelivr.net/npm/swagger-ui-dist@3/swagger-ui-standalone-preset.js'
Examples:

app.config['SWAGGER_UI_STANDALONE_PRESET_JS'] = 'https://cdnjs.cloudflare.com/ajax/libs/swagger-ui/4.11.1/swagger-ui-standalone-preset.min.js'

SWAGGER_UI_LAYOUT¶

The layout of Swagger UI, one of 'BaseLayout' and 'StandaloneLayout'.

Type: str
Default value: 'BaseLayout'
Examples:

app.config['SWAGGER_UI_LAYOUT'] = 'StandaloneLayout'

SWAGGER_UI_CONFIG¶

The config for Swagger UI, these config values will overwrite the existing config, such as SWAGGER_UI_LAYOUT.

Tip

See Configuration of the Swagger UI docs for available config options.

Type: dict
Default value: None
Examples:

app.config['SWAGGER_UI_CONFIG'] = {
    'layout': 'StandaloneLayout'
}

SWAGGER_UI_OAUTH_CONFIG¶

The config for Swagger UI OAuth:

ui.initOAuth(yourConfig)

Tip

See the OAuth 2.0 configuration in Swagger UI docs for available config options.

Type: dict
Default value: None
Examples:

app.config['SWAGGER_UI_OAUTH_CONFIG'] = {
    'realm': 'foo'
}

ELEMENTS_CSS¶

The absolute or relative URL of the Elements CSS file.

Type: str
Default value: 'https://unpkg.com/@stoplight/elements/styles.min.css'
Examples:

app.config['ELEMENTS_CSS'] = 'https://cdn.jsdelivr.net/npm/@stoplight/elements-dev-portal@1.7.4/styles.min.css'

ELEMENTS_JS¶

The absolute or relative URL of the Elements JavaScript file.

Type: str
Default value: 'https://unpkg.com/@stoplight/elements/web-components.min.js'
Examples:

app.config['ELEMENTS_JS'] = 'https://cdn.jsdelivr.net/npm/@stoplight/elements-dev-portal@1.7.4/web-components.min.js'

ELEMENTS_LAYOUT¶

The layout of Elements, one of 'sidebar' and 'stacked'.

Type: str
Default value: 'sidebar'
Examples:

app.config['ELEMENTS_LAYOUT'] = 'stacked'

ELEMENTS_CONFIG¶

The config for Elements, these config values will overwrite the existing config, such as ELEMENTS_LAYOUT.

Tip

See Elements Configuration Options for available config options.

Type: dict
Default value: None
Examples:

app.config['ELEMENTS_CONFIG'] = {
    'hideTryIt': 'true',
    'layout': 'stacked',
}

RAPIDOC_JS¶

The absolute or relative URL of the RapiDoc JavaScript file.

Type: str
Default value: 'https://unpkg.com/rapidoc/dist/rapidoc-min.js'
Examples:

app.config['RAPIDOC_JS'] = 'https://cdn.jsdelivr.net/npm/rapidoc@9.3.2/dist/rapidoc-min.min.js'

RAPIDOC_THEME¶

The theme of RapiDoc, one of 'light' and 'dark'.

Type: str
Default value: 'light'
Examples:

app.config['RAPIDOC_THEME'] = 'dark'

RAPIDOC_CONFIG¶

The config for RapiDoc, these config values will overwrite the existing config, such as RAPIDOC_THEME.

Tip

See RapiDoc API of the RapiDoc docs for available config options.

Type: dict
Default value: None
Examples:

app.config['RAPIDOC_CONFIG'] = {
    'update-route': False,
    'layout': 'row'
}

RAPIPDF_JS¶

The absolute or relative URL of the RapiPDF JavaScript file.

Type: str
Default value: 'https://unpkg.com/rapipdf/dist/rapipdf-min.js'
Examples:

app.config['RAPIPDF_JS'] = 'https://cdn.jsdelivr.net/npm/rapipdf@2.2.1/src/rapipdf.min.js'

RAPIPDF_CONFIG¶

The config for RapiPDF.

Tip

See RapiPDF API of the RapiPDF docs for available config options.

Type: dict
Default value: None
Examples:

app.config['RAPIPDF_CONFIG'] = {
    'include-example': True,
    'button-label': 'Generate!'
}

Flask built-in configuration variables¶

See Builtin Configuration Values for the built-in configuration variables provided by Flask.

Configuration¶

Basics¶

OpenAPI fields¶

OPENAPI_VERSION¶

SERVERS¶

TAGS¶

EXTERNAL_DOCS¶

INFO¶

DESCRIPTION¶

TERMS_OF_SERVICE¶

CONTACT¶

LICENSE¶

OpenAPI spec¶

SPEC_FORMAT¶

LOCAL_SPEC_PATH¶

LOCAL_SPEC_JSON_INDENT¶

SYNC_LOCAL_SPEC¶

JSON_SPEC_MIMETYPE¶

YAML_SPEC_MIMETYPE¶

Automation behavior control¶

AUTO_TAGS¶

AUTO_OPERATION_SUMMARY¶

AUTO_OPERATION_DESCRIPTION¶

AUTO_OPERATION_ID¶

AUTO_200_RESPONSE¶

AUTO_404_RESPONSE¶

AUTO_VALIDATION_ERROR_RESPONSE¶

AUTO_AUTH_ERROR_RESPONSE¶

Response customization¶

SUCCESS_DESCRIPTION¶

NOT_FOUND_DESCRIPTION¶

VALIDATION_ERROR_STATUS_CODE¶

VALIDATION_ERROR_DESCRIPTION¶

VALIDATION_ERROR_SCHEMA¶

AUTH_ERROR_STATUS_CODE¶

AUTH_ERROR_DESCRIPTION¶

HTTP_ERROR_SCHEMA¶

BASE_RESPONSE_SCHEMA¶

BASE_RESPONSE_DATA_KEY¶

API documentation¶

DOCS_FAVICON¶

REDOC_USE_GOOGLE_FONT¶

REDOC_CONFIG¶

REDOC_STANDALONE_JS`¶

SWAGGER_UI_CSS¶

SWAGGER_UI_BUNDLE_JS¶

SWAGGER_UI_STANDALONE_PRESET_JS¶

SWAGGER_UI_LAYOUT¶

SWAGGER_UI_CONFIG¶

SWAGGER_UI_OAUTH_CONFIG¶

ELEMENTS_CSS¶

ELEMENTS_JS¶

ELEMENTS_LAYOUT¶

ELEMENTS_CONFIG¶

RAPIDOC_JS¶

RAPIDOC_THEME¶

RAPIDOC_CONFIG¶

RAPIPDF_JS¶

RAPIPDF_CONFIG¶

Flask built-in configuration variables¶

`AUTO_404_RESPONSE`¶