ui5-test-runner/src/ui5.js

'use strict'

const { dirname, join } = require('path')
const { createWriteStream } = require('fs')
const { mkdir, unlink } = require('fs').promises
const { capture } = require('reserve')
const { getOutput } = require('./output')

module.exports = job => {
  if (job.disableUi5) {
    return []
  }

  const [, hostName] = /https?:\/\/([^/]*)/.exec(job.ui5)
  const [, version] = /(\d+\.\d+\.\d+)?$/.exec(job.ui5)
  const cacheBase = join(job.cache || '', hostName.replace(':', '_'), version || '')
  const match = /\/((?:test-)?resources\/.*)/
  const ifCacheEnabled = (request, url, match) => job.cache ? match : false
  const uncachable = {}
  const cachingInProgress = {}

  const mappings = [{
    /* Prevent caching issues :
     * - Caching was not possible (99% URL does not exist)
     * - Caching is in progress (must wait for the end of the writing stream)
     */
    match,
    'if-match': ifCacheEnabled,
    custom: async (request, response, path) => {
      if (uncachable[path]) {
        response.writeHead(404)
        response.end()
        return
      }
      const cachingPromise = cachingInProgress[path]
      /* istanbul ignore next */ // Hard to reproduce
      if (cachingPromise) {
        await cachingPromise
      }
    }
  }, {
    // UI5 from cache
    match,
    'if-match': ifCacheEnabled,
    file: join(cacheBase, '$1'),
    'ignore-if-not-found': true
  }, {
    // UI5 caching
    method: 'GET',
    match,
    'if-match': ifCacheEnabled,
    custom: async (request, response, path) => {
      const filePath = /([^?#]+)/.exec(unescape(path))[1] // filter URL parameters & hash (assuming resources are static)
      const cachePath = join(cacheBase, filePath)
      const cacheFolder = dirname(cachePath)
      await mkdir(cacheFolder, { recursive: true })
      if (cachingInProgress[path]) {
        return request.url // loop back to use cached result
      }
      const file = createWriteStream(cachePath)
      cachingInProgress[path] = capture(response, file)
        .catch(reason => {
          file.end()
          uncachable[path] = true
          if (response.statusCode !== 404) {
            getOutput(job).failedToCacheUI5resource(path, response.statusCode)
          }
          return unlink(cachePath)
        })
        .then(() => {
          delete cachingInProgress[path]
        })
    }
  }, {
    // UI5 from url
    method: ['GET', 'HEAD'],
    match,
    url: `${job.ui5}/$1`,
    'ignore-unverifiable-certificate': true
  }]

  job.libs.forEach(({ relative, source }) => {
    mappings.unshift({
      match: new RegExp(`\\/resources\\/${relative.replace(/\//g, '\\/')}(.*)`),
      file: join(source, '$1'),
      'ignore-if-not-found': true
    })
  })

  return mappings
}