The paths and operations of your API in the OpenAPI specification.

Introduction

Paths and operations are the building blocks of an API. Paths represent the URL endpoints of the API, while operations represent the HTTP methods (such as GET, POST, PUT, and DELETE) that are supported by those endpoints. In the OpenAPI specification, you can define paths and operations using the paths object.

Defining Paths

To define a path, you need to specify the path as a string and then list the operations that are supported by that path. For example, let's say you have an API that allows users to retrieve a list of products. You can define the path for this API as follows:

"/products":
  get:
    ...

Defining Operations

To define an operation, specify the HTTP method supported by the API endpoint. You can use any of the following HTTP methods in the OpenAPI specification:

• GET
• POST
• PUT
• DELETE
• PATCH
• HEAD
• OPTIONS

For example, let's say you want to define an operation that allows users to retrieve a single product. You can specify this operation as follows:

"/products/{productId}":
  get:
    ...

In this example, we have used the 'get' method to define the operation for retrieving a single product. We have also included a path parameter '{productId}' that represents the unique identifier for the product.

Adding Details to Operations

Once you have defined the paths and operations of your API, you can add additional details to describe the API operation. For example, you can specify the parameters the API operation requires, the expected responses, and any security requirements.

Here's an example of how to add details to an operation:

"/products/{productId}":
  get:
    summary: Retrieve a product by ID
    parameters:
      - name: productId
        in: path
        description: ID of the product to retrieve
        required: true
        schema:
          type: integer
          format: int64
    responses:
      '200':
        description: OK
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Product'
      '404':
        description: Not Found
    security:
      - api_key: []

In this example, we have added a 'summary' field to describe what the API operation does. We have also defined a 'parameter' for the 'productId' path parameter, specifying that it is required and should be an integer. We have also described the expected 'responses', including a 200 OK response and a 404 Not Found response. Finally, we have specified that the API operation requires an API key for authentication.

Conclusion

Defining the paths and operations of your API is an essential part of the API development process. In the OpenAPI specification, you can specify paths and operations using the 'paths' object, and add additional details to describe the API operation. With this guide, you should be able to start defining the paths and operations of your API in the OpenAPI specification.