Serverless Auto Swagger

This plugin allows you to automatically generate a swagger endpoint, describing your application endpoints. This is built from your existing serverless config and typescript definitions, reducing the duplication of work.

Install

yarn add --dev serverless-auto-swagger
# or
npm install -D serverless-auto-swagger

Add the following plugin to your serverless.yml or serverless.ts:

plugins:
  - serverless-auto-swagger

plugins: ['serverless-auto-swagger']

Usage

This plugin is designed to work with vanilla Serverless Framework. All you need to do is add this plugin to your plugin list and it will generate the swagger file and add the endpoints required. When you deploy your API, your new swagger UI will be available at https://{your-url-domain}/swagger.

You can also run sls generate-swagger if you want to generate the swagger file without deploying the application.

Config Options

custom:
    autoswagger:
        apiType?: 'http' | 'httpApi'
        generateSwaggerOnDeploy?: true | false
        typefiles?: ['./src/types/typefile1.d.ts', './src/subfolder/helper.d.ts']
        swaggerFiles?: ['./doc/endpointFromPlugin.json', './doc/iCannotPutThisInHttpEvent.json', './doc/aDefinitionWithoutTypescript.json']
        swaggerPath?: 'string'
        apiKeyHeaders?: 'string[]'
        useStage?: true | false
        basePath?: '/string'
        schemes?: ['http', 'https', 'ws', 'wss']

generateSwaggerOnDeploy is a boolean which decides whether to generate a new swagger file on deployment. Default is true.

typefiles is an array of strings which defines where to find the typescript types to use for the request and response bodies. Default is ./src/types/api-types.d.ts.

swaggerFiles is an array of string which will merge custom json OpenApi 2.0 files to the generated swagger

swaggerPath is a string for customize swagger path. Default is swagger. Your new swagger UI will be available at https://{your-url-domain}/{swaggerPath}

apiType is the optional API type for which your Swagger UI and Swagger JSON lambdas should be deployed. Options are http and httpApi. Defaults to httpApi if not specified.

apiKeyHeaders is an array of strings used to define API keys used in auth headers. For example, if you want to send the Authorization and x-api-key, then you would set:

apiKeyHeaders: ['Authorization', 'x-api-key']

useStage is a bool to either use current stage in beginning of path or not. The Default is false. For example, if you use it enabled (true) and your stage is dev the swagger will be in dev/swagger

basePath is an optional string that can be prepended to every request (i.e. http://localhost/basePath/my-endpoint). Should include leading /.

schemes is an optional array (containing one of http, https, ws, or wss) for specifying schemes. If not provided, uses the scheme used to serve the API specification (reflecting Swagger's behavior)

Adding more details

The default swagger file from vanilla Serverless framework will have the correct paths and methods but no details about the requests or responses.

API Summary and Details

The optional attributes summary and description can be used to describe each HTTP request in Swagger.

swaggerTags is an optional array that can be used to group HTTP requests with a collapsible name (i.e. grouping two endpoints GET /dogs and POST /dogs together). If not specified, all HTTP requests will be grouped under default.

http: {
    summary: 'This is a cool API',
    description: 'Cool API description is here',
    swaggerTags: ['Dogs']
}

Adding Data Types

This plugin uses typescript types to generate the data types for the endpoints. By default, it pulls the types from src/types/api-types.d.ts.

You can then assign these typescript definitions to requests as bodyType on the http or https config, or to the response as seen just below.

Responses

You can also add expected responses to each of the http endpoint events. This is an object that contains the response code with some example details:

responseData: {
    // response with description and response body
    200: {
        description: 'this went well',
        bodyType: 'helloPostResponse',
    },

    // response with just a description
    400: {
        description: 'failed Post',
    },
    // shorthand for just a description
    502: 'server error',
}

Post request expected body

When you create a POST or PUT endpoint, you expect to receive a specific structure of data as the body of the request.

You can do that by adding a bodyType to the http event:

http: {
    path: 'hello',
    method: 'post',
    cors: true,
    bodyType: 'helloPostBody',
}

Query String Parameters

If you want to specify the query string parameters on an endpoint you can do this by adding an object of queryStringParameters to the event (original I know). This has two required properties of required and type as well as an optional description.

http: {
    path: 'goodbye',
    method: 'get',
    queryStringParameters: {
        bob: {
            required: true,
            type: 'string',
            description: 'bob',
        },
        count: {
            required: false,
            type: 'integer',
        },
    },
},

Multi-Valued Query String Parameters

If you use multi-value query string parameters (array), then you must specify that your type is array and specify your data type (string or integer) in arrayItemsType

http: {
    path: 'goodbye',
    method: 'get',
    queryStringParameters: {
        bob: {
            required: true,
            type: 'array',
            arrayItemsType : 'string',
            description: 'bob',
        },
        count: {
            required: false,
            type: 'array',
            arrayItemsType : 'integer',
        },
    },
},

Header Params

Works the same way as queryStringParameters, but for headers.

To use it, just define it under headerParameters:

http: {
    path: 'goodbye',
    method: 'get',
    headerParameters: {
        bob: {
            required: true,
            type: 'string',
            description: 'bob',
        },
        count: {
            required: false,
            type: 'integer',
        },
    },
},

Exclude an endpoint

You can exclude some endpoints from the swagger generation by adding exclude to the http event:

http: {
    path: 'hello',
    method: 'post',
    exclude: true,
}

with Serverless Offline

In the plugin list, you must list serverless-auto-swagger before the serverless-offline plugin. If you don't you won't get the required endpoints added to your local endpoints.