This code generator creates pydantic model and dataclasses.dataclass from an openapi file and others.
See documentation for more details.
To install datamodel-code-generator:
$ pip install datamodel-code-generatorYou can generate models from a local file.
$ datamodel-codegen --input api.yaml --output model.pyapi.yaml
openapi: "3.0.0"
info:
version: 1.0.0
title: Swagger Petstore
license:
name: MIT
servers:
- url: http://petstore.swagger.io/v1
paths:
/pets:
get:
summary: List all pets
operationId: listPets
tags:
- pets
parameters:
- name: limit
in: query
description: How many items to return at one time (max 100)
required: false
schema:
type: integer
format: int32
responses:
'200':
description: A paged array of pets
headers:
x-next:
description: A link to the next page of responses
schema:
type: string
content:
application/json:
schema:
$ref: "#/components/schemas/Pets"
default:
description: unexpected error
content:
application/json:
schema:
$ref: "#/components/schemas/Error"
x-amazon-apigateway-integration:
uri:
Fn::Sub: arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${PythonVersionFunction.Arn}/invocations
passthroughBehavior: when_no_templates
httpMethod: POST
type: aws_proxy
post:
summary: Create a pet
operationId: createPets
tags:
- pets
responses:
'201':
description: Null response
default:
description: unexpected error
content:
application/json:
schema:
$ref: "#/components/schemas/Error"
x-amazon-apigateway-integration:
uri:
Fn::Sub: arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${PythonVersionFunction.Arn}/invocations
passthroughBehavior: when_no_templates
httpMethod: POST
type: aws_proxy
/pets/{petId}:
get:
summary: Info for a specific pet
operationId: showPetById
tags:
- pets
parameters:
- name: petId
in: path
required: true
description: The id of the pet to retrieve
schema:
type: string
responses:
'200':
description: Expected response to a valid request
content:
application/json:
schema:
$ref: "#/components/schemas/Pets"
default:
description: unexpected error
content:
application/json:
schema:
$ref: "#/components/schemas/Error"
x-amazon-apigateway-integration:
uri:
Fn::Sub: arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${PythonVersionFunction.Arn}/invocations
passthroughBehavior: when_no_templates
httpMethod: POST
type: aws_proxy
components:
schemas:
Pet:
required:
- id
- name
properties:
id:
type: integer
format: int64
name:
type: string
tag:
type: string
Pets:
type: array
items:
$ref: "#/components/schemas/Pet"
Error:
required:
- code
- message
properties:
code:
type: integer
format: int32
message:
type: string
apis:
type: array
items:
type: object
properties:
apiKey:
type: string
description: To be used as a dataset parameter value
apiVersionNumber:
type: string
description: To be used as a version parameter value
apiUrl:
type: string
format: uri
description: "The URL describing the dataset's fields"
apiDocumentationUrl:
type: string
format: uri
description: A URL to the API console for each APImodel.py
# generated by datamodel-codegen:
# filename: api.yaml
# timestamp: 2020-06-02T05:28:24+00:00
from __future__ import annotations
from typing import List, Optional
from pydantic import AnyUrl, BaseModel, Field
class Pet(BaseModel):
id: int
name: str
tag: Optional[str] = None
class Pets(BaseModel):
__root__: List[Pet]
class Error(BaseModel):
code: int
message: str
class Api(BaseModel):
apiKey: Optional[str] = Field(
None, description='To be used as a dataset parameter value'
)
apiVersionNumber: Optional[str] = Field(
None, description='To be used as a version parameter value'
)
apiUrl: Optional[AnyUrl] = Field(
None, description="The URL describing the dataset's fields"
)
apiDocumentationUrl: Optional[AnyUrl] = Field(
None, description='A URL to the API console for each API'
)
class Apis(BaseModel):
__root__: List[Api]These OSS use datamodel-code-generator to generate many models. We can learn about use-cases from these projects.
- Netflix/consoleme
- DataDog/integrations-core
- awslabs/aws-lambda-powertools-python
- Not used. But, introduced advanced-use-cases in the official document
- open-metadata/OpenMetadata
- airbytehq/airbyte
- IBM/compliance-trestle
- SeldonIO/MLServer
- OpenAPI 3 (YAML/JSON, OpenAPI Data Type)
- JSON Schema (JSON Schema Core/JSON Schema Validation)
- JSON/YAML/CSV Data (it will be converted to JSON Schema)
- Python dictionary (it will be converted to JSON Schema)
- pydantic.BaseModel
- dataclasses.dataclass
To install datamodel-code-generator:
$ pip install datamodel-code-generatorIf you want to resolve $ref for remote files then you should specify http extra option.
$ pip install datamodel-code-generator[http]The docker image is in Docker Hub
$ docker pull koxudaxi/datamodel-code-generatorYou can genearte models from a URL.
$ datamodel-codegen --url https://<INPUT FILE URL> --output model.pyThis method needs http extra option
The datamodel-codegen command:
usage: datamodel-codegen [-h] [--input INPUT] [--url URL]
[--http-headers HTTP_HEADER [HTTP_HEADER ...]]
[--http-ignore-tls]
[--input-file-type {auto,openapi,jsonschema,json,yaml,dict,csv}]
[--output-model-type {pydantic.BaseModel,dataclasses.dataclass}]
[--openapi-scopes {schemas,paths,tags,parameters} [{schemas,paths,tags,parameters} ...]]
[--output OUTPUT] [--base-class BASE_CLASS]
[--field-constraints] [--use-annotated]
[--use-non-positive-negative-number-constrained-types]
[--field-extra-keys FIELD_EXTRA_KEYS [FIELD_EXTRA_KEYS ...]]
[--field-include-all-keys]
[--field-extra-keys-without-x-prefix FIELD_EXTRA_KEYS_WITHOUT_X_PREFIX [FIELD_EXTRA_KEYS_WITHOUT_X_PREFIX ...]]
[--snake-case-field]
[--original-field-name-delimiter ORIGINAL_FIELD_NAME_DELIMITER]
[--strip-default-none]
[--disable-appending-item-suffix]
[--allow-population-by-field-name]
[--allow-extra-fields] [--enable-faux-immutability]
[--use-default] [--force-optional]
[--strict-nullable]
[--strict-types {str,bytes,int,float,bool} [{str,bytes,int,float,bool} ...]]
[--disable-timestamp] [--use-standard-collections]
[--use-generic-container-types]
[--use-union-operator] [--use-schema-description]
[--use-field-description] [--use-default-kwarg]
[--reuse-model] [--keep-model-order]
[--collapse-root-models]
[--enum-field-as-literal {all,one}] [--use-one-literal-as-default]
[--set-default-enum-member]
[--empty-enum-field-name EMPTY_ENUM_FIELD_NAME]
[--capitalise-enum-members]
[--special-field-name-prefix SPECIAL_FIELD_NAME_PREFIX]
[--remove-special-field-name-prefix]
[--use-subclass-enum] [--class-name CLASS_NAME]
[--use-title-as-name]
[--custom-template-dir CUSTOM_TEMPLATE_DIR]
[--extra-template-data EXTRA_TEMPLATE_DATA]
[--aliases ALIASES]
[--target-python-version {3.6,3.7,3.8,3.9,3.10,3.11}]
[--wrap-string-literal] [--validation]
[--use-double-quotes] [--encoding ENCODING] [--debug]
[--disable-warnings] [--version]
options:
-h, --help show this help message and exit
--input INPUT Input file/directory (default: stdin)
--url URL Input file URL. `--input` is ignored when `--url` is
used
--http-headers HTTP_HEADER [HTTP_HEADER ...]
Set headers in HTTP requests to the remote host.
(example: "Authorization: Basic dXNlcjpwYXNz")
--http-ignore-tls Disable verification of the remote host's TLS
certificate
--input-file-type {auto,openapi,jsonschema,json,yaml,dict,csv}
Input file type (default: auto)
--output-model-type {pydantic.BaseModel,dataclasses.dataclass}
Output model type (default: pydantic.BaseModel)
--openapi-scopes {schemas,paths,tags,parameters} [{schemas,paths,tags,parameters} ...]
Scopes of OpenAPI model generation (default: schemas)
--output OUTPUT Output file (default: stdout)
--base-class BASE_CLASS
Base Class (default: pydantic.BaseModel)
--field-constraints Use field constraints and not con* annotations
--use-annotated Use typing.Annotated for Field(). Also, `--field-
constraints` option will be enabled.
--use-non-positive-negative-number-constrained-types
Use the Non{Positive,Negative}{FloatInt} types instead
of the corresponding con* constrained types.
--field-extra-keys FIELD_EXTRA_KEYS [FIELD_EXTRA_KEYS ...]
Add extra keys to field parameters
--field-include-all-keys
Add all keys to field parameters
--field-extra-keys-without-x-prefix
Add extra keys with `x-` prefix to field parameters.
The extra keys are stripped of the `x-` prefix.
--snake-case-field Change camel-case field name to snake-case
--original-field-name-delimiter ORIGINAL_FIELD_NAME_DELIMITER
Set delimiter to convert to snake case. This option
only can be used with --snake-case-field (default: `_`
)
--strip-default-none Strip default None on fields
--disable-appending-item-suffix
Disable appending `Item` suffix to model name in an
array
--allow-population-by-field-name
Allow population by field name
--allow-extra-fields Allow to pass extra fields, if this flag is not
passed, extra fields are forbidden.
--enable-faux-immutability
Enable faux immutability
--use-default Use default value even if a field is required
--force-optional Force optional for required fields
--strict-nullable Treat default field as a non-nullable field (Only
OpenAPI)
--strict-types {str,bytes,int,float,bool} [{str,bytes,int,float,bool} ...]
Use strict types
--disable-timestamp Disable timestamp on file headers
--use-standard-collections
Use standard collections for type hinting (list, dict)
--use-generic-container-types
Use generic container types for type hinting
(typing.Sequence, typing.Mapping). If `--use-standard-
collections` option is set, then import from
collections.abc instead of typing
--use-union-operator Use | operator for Union type (PEP 604).
--use-schema-description
Use schema description to populate class docstring
--use-field-description
Use schema description to populate field docstring
--use-default-kwarg Use `default=` instead of a positional argument for
Fields that have default values.
--reuse-model Re-use models on the field when a module has the model
with the same content
--keep-model-order Keep generated models' order
--collapse-root-models
Models generated with a root-type field will be
mergedinto the models using that root-type model
--enum-field-as-literal {all,one}
Parse enum field as literal. all: all enum field type
are Literal. one: field type is Literal when an enum
has only one possible value
--use-one-literal-as-default
Use one literal as default value for one literal field
--set-default-enum-member
Set enum members as default values for enum field
--empty-enum-field-name EMPTY_ENUM_FIELD_NAME
Set field name when enum value is empty (default: `_`)
--capitalise-enum-members
Capitalize field names on enum
--special-field-name-prefix SPECIAL_FIELD_NAME_PREFIX
Set field name prefix when first character can't be
used as Python field name (default: `field`)
--remove-special-field-name-prefix
Remove field name prefix when first character can't be
used as Python field name
--use-subclass-enum Define Enum class as subclass with field type when
enum has type (int, float, bytes, str)
--class-name CLASS_NAME
Set class name of root model
--use-title-as-name use titles as class names of models
--custom-template-dir CUSTOM_TEMPLATE_DIR
Custom template directory
--extra-template-data EXTRA_TEMPLATE_DATA
Extra template data
--aliases ALIASES Alias mapping file
--target-python-version {3.6,3.7,3.8,3.9,3.10,3.11}
target python version (default: 3.7)
--wrap-string-literal
Wrap string literal by using black `experimental-
string-processing` option (require black 20.8b0 or
later)
--validation Enable validation (Only OpenAPI)
--use-double-quotes Model generated with double quotes. Single quotes or
your black config skip_string_normalization value will
be used without this option.
--encoding ENCODING The encoding of input and output (default: cp1252)
--debug show debug message
--disable-warnings disable warnings
--version show version- string (include patter/minLength/maxLenght)
- number (include maximum/exclusiveMaximum/minimum/exclusiveMinimum/multipleOf/le/ge)
- integer (include maximum/exclusiveMaximum/minimum/exclusiveMinimum/multipleOf/le/ge)
- boolean
- array
- object
- date
- datetime
- time
- password
- idn-email
- uuid (uuid1/uuid2/uuid3/uuid4/uuid5)
- ipv4
- ipv6
- ipv4-network
- ipv6-network
- hostname
- decimal
- enum (as enum.Enum or typing.Literal)
- allOf (as Multiple inheritance)
- anyOf (as typing.Union)
- oneOf (as typing.Union)
- $ref (http extra is required when resolving $ref for remote files.)
- $id (for JSONSchema)
This code generator creates FastAPI app from an openapi file.
https://github.com/koxudaxi/fastapi-code-generator
A JetBrains PyCharm plugin for pydantic.
https://github.com/koxudaxi/pydantic-pycharm-plugin
https://pypi.org/project/datamodel-code-generator
datamodel-code-generator is released under the MIT License. http://www.opensource.org/licenses/mit-license