html-validator.ts

// gulp-w3c-html-validator
// Gulp plugin to validate HTML using the W3C Markup Validation Service
// https://github.com/center-key/gulp-w3c-html-validator
// MIT License

// Types
export type AnalyzerOptions = ValidatorOptions;
export type ReporterSettings = {
   maxMessageLen: number,
   throwErrors:   boolean,
   };
export type ReporterOptions = Partial<ReporterSettings>;

// Imports
import { Transform } from 'stream';
import { ValidatorOptions, ValidatorResults, w3cHtmlValidator } from 'w3c-html-validator';
import PluginError from 'plugin-error';
import through2 from 'through2';

// Setup
const pluginName = 'gulp-w3c-html-validator';

// Gulp plugin
const htmlValidator = {

   analyzer(options: AnalyzerOptions): Transform {
      const validate: through2.TransformFunction = (file, _encoding, done) => {
         const handleValidation = (results: ValidatorResults) => {
            file.w3cHtmlValidator = results;
            done(null, file);
            };
         const validatorOptions = { ...options, ...{ html: file.contents.toString() } };
         if (file.isNull())
            done(null, file);
         else if (file.isStream())
            done(new PluginError(pluginName, 'Streaming not supported'));
         else
            w3cHtmlValidator.validate(validatorOptions).then(handleValidation);
         };
      return through2.obj(validate);
      },

   reporter(options: ReporterOptions): Transform {
      const defaults = { maxMessageLen: null, throwErrors: false };
      const settings = { ...defaults, ...options };
      const report: through2.TransformFunction = (file, _encoding, done) => {
         const reporterOptions = {
            title:          file.path,
            maxMessageLen:  settings.maxMessageLen,
            continueOnFail: true,
            };
         if (file.w3cHtmlValidator)
            w3cHtmlValidator.reporter(file.w3cHtmlValidator, reporterOptions);
         done(null, file);
         if (settings.throwErrors && file.w3cHtmlValidator && !file.w3cHtmlValidator.validates)
            throw new PluginError(pluginName, 'HTML validation failed');
         };
      return through2.obj(report);
      },

   };

export { htmlValidator };