Automatic Validation of Swagger API Request In Express?

Question

Excuse me if this question seems obvious, but I am new to Express, Node, and Swagger.

I have written a Swagger specification for an API.

Are there tools in which you can pass a request to a Swagger documented API along with the Swagger.json file to validate that the required parameters are there, that the enum values for those parameters are correct, etc.?

Something akin to:

validator.validate ("./swagger.json", req, function (req, res, err) {
     if (err) {
       res.status('400').send(err.message());
     }
     else {
       // Call my controller
       swaggerController(req, res);
     }
});

I believe there is, but it's difficult to find or I'm not looking for the correct thing.

Answer 1

Yes, you can do this. There is a generator project that does exactly this, express-no-stress. Get it here:

When using it, each API request will be validated against your Swagger API description, provided by you, in Api.yaml.

For example, to validate the body of a POST request to /examples, you can do the following:

Edit Api.yaml

...
definitions:
  # define the example body i.e. require the property name
  ExampleBody:
    type: object
    title: example
    required:
      - name
    properties:
      name:
        type: string
        description: The example name
paths:
  # define your /examples POST endpoint
  # reference the ExamplesBody definition from above
  /examples:
    post:
      tags:
        - Examples
      description: Create a new example
      parameters:
        - name: example
          in: body
          description: number of items to skip
          required: true
          schema: 
            $ref: "#/definitions/ExampleBody"
      responses:
        200:
          description: Returns all examples
...

Next, in the Node.js code create a route handler for POSTs to /examples

e.g.

app.post('/examples', function (req, res) { /* your handler logic here */ /* no need to validate the request payload. it will be done automatically */ });

Note: include only your handler logic. Body validation will be handled automatically.