Pa11y CI Reporter Runner

Pa11y CI Reporter Runner facilitates testing of Pa11y CI reporters. Given a Pa11y CI JSON results file and optional configuration it performs the Pa11y CI calls to the reporter, including proper transformation of results and configuration data. Functionally, it's an emulation of the Pa11y CI side of the reporter interface with explicit control over execution of each step.

Installation

Install Pa11y CI Reporter Runner via npm.

npm install pa11y-ci-reporter-runner

Usage

Pa11y CI Reporter Runner exports a factory function createRunner that creates a reporter runner. This function takes four arguments:

• resultsFileName: Path to a Pa11y CI JSON results file.
• reporterName: Name of the reporter to execute. Can be an npm module, for example pa11y-ci-reporter-html, or a path to a reporter file.
• options: Optional reporter options.
• config: Optional Pa11y CI configuration file that produces the Pa11y CI JSON results.

Runner states

Pa11y CI Reporter Runner emulates calls from Pa11y CI to the given reporter for the given results file. There are five distinct states for the runner, as shown below:

%% It's unfortunate that mermaid charts don't render on npmjs.com,
%% see the README in the repository to view the flowchart
flowchart LR;
    init-->beforeAll;
    beforeAll-->beginUrl;
    beginUrl-->urlResults;
    urlResults-->beginUrl;
    urlResults-->afterAll;

• init: The initial state of the runner.
• beforeAll: In this state the runner calls the reporter beforeAll function.
• beginUrl: In this state the runner calls the reporter begin function for a given URL.
• urlResults: In this state the runner calls the reporter results or error function depending on the result for that URL. If there are subsequent URLs, the runner next moves to beginUrl for the next URL. If this is the last URL, the runner moves to afterAll.
• afterAll: In this state the runner calls the reporter afterAll function.

When calling reporter functions, the runner transforms the Pa11y CI results and configuration data to provide the appropriate arguments. For example, the results function is called with the results as returned from Pa11y (slightly different than those returned from Pa11y CI) and the consolidated configuration for the analysis of that URL.

The runner state can be obtained via the following runner functions:

• getCurrentState(): The current state of the runner.
• getNextState(): The next state of the runner (that is, the state that would be obtained by calling the runNext() function).

Both functions return an object with the following properties:

• state: The current runner state (any state value shown previously)
• url: The current URL for any state with an applicable URL (beginUrl and urlResults), otherwise undefined.

Runner execution

The reporter runner has five control functions:

• runAll(): Simulates Pa11y CI running the analysis from the provided JSON results file from the current state through the end, calling all associated reporter functions.
• runNext(): Simulates Pa11y CI running through the next state from the provided JSON results file, calling the associated reporter function as noted previously.
• runUntil(targetState, targetUrl): Simulates Pa11y CI running the analysis from the provided JSON results file from the current state through the specified state/URL, calling the associated reporter functions as noted above. An error is thrown if the end of the results are reached and the target wasn't found. This function takes the following arguments:
  • targetState: The target state of the runner (any state noted previously except init, or any valid value of the RunnerStates enum).
  • targetUrl: An optional target URL. If no URL is specified, the runner stops at the first instance of the target state.
• runUntilNext(targetState, targetUrl): Provides the same capability as runUntil, but execution ends at the state prior to the target state/URL, so that the target would execute if runNext() is subsequently called.
• reset(): Resets the runner to the init state and re-initializes the reporter. This can be sent from any state.

These command are all asynchronous and must be completed before another is sent, otherwise an error is thrown. In addition, once a run has been completed and the runner is in the afterAll state it must be reset before accepting any run command.

Example

A complete example is provided below:

const { createRunner, RunnerStates } = require('pa11y-ci-reporter-runner');

const resultsFileName = 'pa11yci-results.json';
const reporterName = '../test-reporter.js';
const reporterOptions = { isSomething: true };
const config = {
  defaults: {
    timeout: 30000
  },
  urls: [
    'http://localhost:8080/page1-with-errors.html',
    'http://localhost:8080/page1-no-errors.html',
    {
      url: 'https://pa11y.org/timed-out.html',
      timeout: 50
    }
  ]
};

test('test all reporter functions', async () => {
  const runner = createRunner(
    resultsFileName,
    reporterName,
    reporterOptions,
    config
  );

  await runner.runAll();

  // Test reporter results
});

test('test reporter at urlResults state', async () => {
  const runner = createRunner(
    resultsFileName,
    reporterName,
    reporterOptions,
    config
  );

  await runner.runUntil(
    RunnerStates.beginUrl,
    'http://localhost:8080/page1-no-errors.html'
  );
  let currentState = runner.getCurrentState();
  // { state: "beginUrl", url: "http://localhost:8080/page1-no-errors.html" }
  const nextState = runner.getNextState();
  // { state: "urlResults", url: "http://localhost:8080/page1-no-errors.html" }
  await runner.runNext();
  currentState = runner.getCurrentState();
  // { state: "urlResults", url: "http://localhost:8080/page1-no-errors.html" }

  // Test reporter results
});

Limitations

When passing config to results, error, and afterAll, Pa11y CI Reporter Runner includes the same properties as Pa11y CI except the browser property (with the puppeteer browser object used by Pa11y CI). If the browser object is needed, testing should be done with Pa11y CI to ensure proper browser capabilities are available.