OpenApiCoverage for NodeJS

Measures code coverage in terms of calls being made to an API specified by an OpenAPI specification.

Installation

  npm install -D @berlund/openapicoverage

Usage

Just import the Code coverage class and hand over your Axios instance to it. Then point it to your OpenApi specification and you're good to go:

const axios = require('axios');
const { OpenApiCoverage } = require('@berlund/openapicoverage');

const axiosInstance = axios.create();
const coverage = OpenApiCoverage.use(axiosInstance).withSpecificationFromFile('./openapi.yaml');

Run your tests as usual, e.g.

  it('should run', async() => {
      await axiosInstance.get('https://example.com/some/path');
      await axiosInstance.get('https://example.com/some/path');
      await axiosInstance.post('https://example.com/path/to/post', {data: 'foo'});
  })

Multiple Axios instances

Multiple Axios instances can be chained:

OpenApiCoverage.use(firstAxiosInstance).use(anotherAxiosInstance)

Options for API definition

In case the path of your API calls isn't entirely defined in the API's paths but in the base path of your specification, a path prefix is accepted:

.withSpecification(path, { pathPrefix: '/v1' })

Report generation

Console

After your tests have been run, you can print a coverage report on the console.

 afterAll(() => {
    coverage.printCoverage();
  })

This will result in something like the following.

    ╔══════════════════════════════════╤════════╤════════╤═══════╗
    ║ Path                             │ Method │ Status │ Count ║
    ╟──────────────────────────────────┼────────┼────────┼───────╢
    ║ https://example.com/some/path    │ get    │ 200    │ 2     ║
    ╟──────────────────────────────────┼────────┼────────┼───────╢
    ║ https://example.com/path/to/post │ post   │ 202    │ 1     ║
    ╚══════════════════════════════════╧════════╧════════╧═══════╝

The following options will output all combinations of path, method and response status, even if they haven't been called:

coverage.printCoverage({ showZeroCounts: true })

File report

Another option is to configure a file output which is updated on every Api call:

OpenApiCoverage.use(axiosInstance, options)

where options can have the following properties:

Property	type	Description
outputFormat	none | html	none disables file output (default) or simple HTML formatted output
outputPath	string	A file path where output should be written to. Ignored if output format is set to none. Will default to the current working directory