# Use Open API data model

## Use Open API data model

## Prepare the REST API to Open API (swagger).

* To be simple comparison, I migrated [bookstore\_api](https://github.com/ccapeng/bookstore_api) project to [bookstore\_openapi](https://github.com/ccapeng/bookstore_openapi).
* What's in the bookstore\_openapi project?
  * Install [drf-yasg](https://github.com/axnsan12/drf-yasg) : `pip install -U drf-yasg`
* The lastest `djangorestframework` is 3.12, which is not compatible with `drf-yasg`.

  Make sure you have `pip install djangorestframework==3.11.1`
* Also check drf-yasg document <https://github.com/axnsan12/drf-yasg> for how to set up `settings.py` and `urls.py`
* Then copy the whole book models, serializers, api.
* Start server. In browser, open `http://127.0.0.1:8000/swagger.yaml`.

## Code Generator

* <https://openapi-generator.tech/> : this is openapi code generator home page,  &#x20;

  you may got lost in here.
* [jar file repository page](https://repo1.maven.org/maven2/org/openapitools/openapi-generator-cli/),\
  to download the latest one.\
  Or in windows, open PowerShell to download it :

  `Invoke-WebRequest -OutFile swagger-codegen-cli.jar https://repo1.maven.org/maven2/io/swagger/swagger-codegen-cli/2.4.15/swagger-codegen-cli-2.4.15.jar`
* To use cli
  * Generate Flask code

    ```
      d:\dvp\swagger>java -jar openapi-generator-cli.jar generate ^
        -i bookstore.yaml ^
        -g python-flask ^
        -o samples/bookstore/flask
    ```
  * Generate nodejs code : use the swagger-codegen-cli.jar.

    ```
      d:\dvp\swagger>java -jar swagger-codegen-cli.jar generate ^
        -i bookstore.yaml ^
        -l nodejs-server ^
        -o samples/bookstore/nodejs
    ```
  * Generate go code

    ```
      d:\dvp\swagger>java -jar openapi-generator-cli.jar generate ^
        -i bookstore.yaml ^
        -g go-gin-server ^
        -o samples/bookstore/gin
    ```

    ```
      d:\dvp\swagger>java -jar openapi-generator-cli.jar generate ^
        -i bookstore.yaml ^
        -g go-server ^
        -o samples/bookstore/go
    ```
  * [More generators](https://openapi-generator.tech/docs/generators)
* Actually, \[django REST framework support] OpenAPI(<https://www.django-rest-framework.org/community/3.10-announcement/>); however, the way to download yaml file is odd. Need further investigate.