Fix python-fastapi free-form objects mapping and forward ref type hints (#9723)

* map free-form objects to Dict[str, Any]

* support Forward Type References

Forward type references will be supported by default from Python 3.10 on only. Until then (and starting with Python 3.7), we can opt in by a __future__ import, cf. https://docs.python.org/3.9/whatsnew/3.7.html?highlight=forward#pep-563-postponed-evaluation-of-annotations

* re-created pet-store sample

* bump required Python version to 3.7 for generated FastAPI projects

* make pydantic modell classes process forward type references

modules/openapi-generator/src/main/resources/python-fastapi/Dockerfile.mustache

@@ -1,4 +1,4 @@
-FROM python:3.6 AS builder
+FROM python:3.7 AS builder
 
 WORKDIR /usr/src/app
 
@@ -11,7 +11,7 @@ COPY . .
 RUN pip install --no-cache-dir .
 
 
-FROM python:3.6 AS test_runner
+FROM python:3.7 AS test_runner
 WORKDIR /tmp
 COPY --from=builder /venv /venv
 COPY --from=builder /usr/src/app/tests tests
@@ -24,7 +24,7 @@ RUN pip install pytest
 RUN pytest tests
 
 
-FROM python:3.6 AS service
+FROM python:3.7 AS service
 WORKDIR /root/app/site-packages
 COPY --from=test_runner /venv /venv
 ENV PATH=/venv/bin:$PATH

modules/openapi-generator/src/main/resources/python-fastapi/README.mustache

@@ -10,7 +10,7 @@ This Python package is automatically generated by the [OpenAPI Generator](https:
 
 ## Requirements.
 
-Python >= 3.6
+Python >= 3.7
 
 ## Installation & Usage
 

modules/openapi-generator/src/main/resources/python-fastapi/model.mustache

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 {{#models}}
@@ -71,3 +72,5 @@ class {{classname}}(BaseModel):
 {{/vars}}
 {{/model}}
 {{/models}}
+
+{{classname}}.update_forward_refs()

modules/openapi-generator/src/main/resources/python-fastapi/model_field_type.mustache

@@ -1 +1 @@
-{{#isEmail}}EmailStr{{/isEmail}}{{#isUri}}AnyUrl{{/isUri}}{{^isEmail}}{{^isUri}}{{dataType}}{{/isUri}}{{/isEmail}}
+{{#isEmail}}EmailStr{{/isEmail}}{{#isUri}}AnyUrl{{/isUri}}{{#isFreeFormObject}}Dict[str, Any]{{/isFreeFormObject}}{{^isEmail}}{{^isUri}}{{^isFreeFormObject}}{{dataType}}{{/isFreeFormObject}}{{/isUri}}{{/isEmail}}

modules/openapi-generator/src/main/resources/python-fastapi/setup_cfg.mustache

@@ -4,11 +4,11 @@ version = {{appVersion}}
 description = {{appDescription}}
 long_description = file: README.md
 keywords = OpenAPI {{appName}}
-python_requires = >= 3.6.*
+python_requires = >= 3.7.*
 classifiers =
     Operating System :: OS Independent
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
 
 [options]
 install_requires =

samples/server/petstore/python-fastapi/Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.6 AS builder
+FROM python:3.7 AS builder
 
 WORKDIR /usr/src/app
 
@@ -11,7 +11,7 @@ COPY . .
 RUN pip install --no-cache-dir .
 
 
-FROM python:3.6 AS test_runner
+FROM python:3.7 AS test_runner
 WORKDIR /tmp
 COPY --from=builder /venv /venv
 COPY --from=builder /usr/src/app/tests tests
@@ -24,7 +24,7 @@ RUN pip install pytest
 RUN pytest tests
 
 
-FROM python:3.6 AS service
+FROM python:3.7 AS service
 WORKDIR /root/app/site-packages
 COPY --from=test_runner /venv /venv
 ENV PATH=/venv/bin:$PATH

samples/server/petstore/python-fastapi/README.md

@@ -7,7 +7,7 @@ This Python package is automatically generated by the [OpenAPI Generator](https:
 
 ## Requirements.
 
-Python >= 3.6
+Python >= 3.7
 
 ## Installation & Usage
 

samples/server/petstore/python-fastapi/setup.cfg

@@ -4,11 +4,11 @@ version = 1.0.0
 description = This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
 long_description = file: README.md
 keywords = OpenAPI OpenAPI Petstore
-python_requires = >= 3.6.*
+python_requires = >= 3.7.*
 classifiers =
     Operating System :: OS Independent
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
 
 [options]
 install_requires =

samples/server/petstore/python-fastapi/src/openapi_server/models/api_response.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 
@@ -23,3 +24,5 @@ class ApiResponse(BaseModel):
     code: Optional[int] = None
     type: Optional[str] = None
     message: Optional[str] = None
+
+ApiResponse.update_forward_refs()

samples/server/petstore/python-fastapi/src/openapi_server/models/category.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 
@@ -26,3 +27,5 @@ class Category(BaseModel):
     def name_pattern(cls, value):
         assert value is not None and re.match(r"^[a-zA-Z0-9]+[a-zA-Z0-9\.\-_]*[a-zA-Z0-9]+$", value)
         return value
+
+Category.update_forward_refs()

samples/server/petstore/python-fastapi/src/openapi_server/models/order.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 
@@ -29,3 +30,5 @@ class Order(BaseModel):
     ship_date: Optional[datetime] = None
     status: Optional[str] = None
     complete: Optional[bool] = None
+
+Order.update_forward_refs()

samples/server/petstore/python-fastapi/src/openapi_server/models/pet.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 from openapi_server.models.category import Category
@@ -31,3 +32,5 @@ class Pet(BaseModel):
     photo_urls: List[str]
     tags: Optional[List[Tag]] = None
     status: Optional[str] = None
+
+Pet.update_forward_refs()

samples/server/petstore/python-fastapi/src/openapi_server/models/tag.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 
@@ -21,3 +22,5 @@ class Tag(BaseModel):
 
     id: Optional[int] = None
     name: Optional[str] = None
+
+Tag.update_forward_refs()

samples/server/petstore/python-fastapi/src/openapi_server/models/user.py

@@ -1,9 +1,10 @@
 # coding: utf-8
 
+from __future__ import annotations
 from datetime import date, datetime  # noqa: F401
 
 import re  # noqa: F401
-from typing import Dict, List, Optional  # noqa: F401
+from typing import Any, Dict, List, Optional  # noqa: F401
 
 from pydantic import AnyUrl, BaseModel, EmailStr, validator  # noqa: F401
 
@@ -33,3 +34,5 @@ class User(BaseModel):
     password: Optional[str] = None
     phone: Optional[str] = None
     user_status: Optional[int] = None
+
+User.update_forward_refs()