server/site/js/source/base-http-extensions.js

/*
 Licensed to the Apache Software Foundation (ASF) under one or more
 contributor license agreements.  See the NOTICE file distributed with
 this work for additional information regarding copyright ownership.
 The ASF licenses this file to You under the Apache License, Version 2.0
 (the "License"); you may not use this file except in compliance with
 the License.  You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */


// URL calls currently 'in escrow'. This controls the spinny wheel animation
var async_escrow = {}
var async_maxwait = 250; // ms to wait before displaying spinner
var async_status = 'clear';
var async_cache = {}

// Escrow spinner check
async function escrow_check() {
    let now = new Date();
    let show_spinner = false;
    for (var k in async_escrow) {
        if ( (now - async_escrow[k]) > async_maxwait ) {
            show_spinner = true;
            break;
        }
    }
    // Fetch or create the spinner
    let spinner = document.getElementById('spinner');
    if (!spinner) {
        spinner = new HTML('div', { id: 'spinner', class: 'spinner'});
        spinwheel = new HTML('div', {id: 'spinwheel', class: 'spinwheel'});
        spinner.inject(spinwheel);
        spinner.inject(new HTML('h2', {}, "Loading, please wait.."));
        document.body.appendChild(spinner);
    }
    // Show or don't show spinner?
    if (show_spinner) {
        spinner.style.display = 'block';
        if (async_status === 'clear') {
            console.log("Waiting for JSON resource, deploying spinner");
            async_status = 'waiting';
        }
    } else {
        spinner.style.display = 'none';
        if (async_status === 'waiting') {
            console.log("All URLs out of escrow, dropping spinner");
            async_status = 'clear';
        }
    }
}

async function async_snap(error) {
    msg = await error.text();
    msg = (msg||"An unknown error occured, possibly an internal browser issue").replace(/<.*?>/g, ""); // strip HTML tags
    modal("An error occured", "An error code %u occured while trying to fetch %s:\n%s".format(error.status, error.url, msg), "error");
}


// Asynchronous GET call
async function GET(url, callback, state, snap, method, body) {
    method = method || 'get'
    console.log("Fetching JSON resource at %s".format(url))
    let pkey = "GET-%s-%s".format(callback, url);
    let res = undefined;
    let res_json = undefined;
    state = state || {};
    state.url = url;
    if (state && state.cached === true && async_cache[url]) {
        console.log("Fetching %s from cache".format(url));
        res_json = async_cache[url];
    }
    else {
        try {
            let meta = {method: method, credentials: 'include', referrerPolicy: 'unsafe-url', headers: {'x-original-referral': document.referrer}};
            if (body) {
                meta.body = body;
            }
            console.log("putting %s in escrow...".format(url));
            async_escrow[pkey] = new Date(); // Log start of request in escrow dict
            const rv = await fetch(url, meta); // Wait for resource...

            // Since this is an async request, the request may have been canceled
            // by the time we get a response. Only do callback if not.
            if (async_escrow[pkey] !== undefined) {
                delete async_escrow[pkey]; // move out of escrow when fetched
                res = rv;
            }
        }
        catch (e) {
            delete async_escrow[pkey]; // move out of escrow if failed
            console.log("The URL %s could not be fetched: %s".format(url, e));
            if (snap) snap({}, {reason: e});
            else {
                modal("An error occured", "An error occured while trying to fetch %s:\n%s".format(url, e), "error");
            }
        }
    }
    if (res !== undefined || res_json !== undefined) {
        // We expect a 2xx return code (usually 200 or 201), snap otherwise
        if ((res_json) || (res.status >= 200 && res.status < 300)) {
            console.log("Successfully fetched %s".format(url))
            if (res_json) {
                js = res_json;
            } else {
                js = await res.json();
                async_cache[url] = js;
            }
            if (callback) {
                callback(state, js);
            } else {
                console.log("No callback function was registered for %s, ignoring result.".format(url));
            }
        } else {
            console.log("URL %s returned HTTP code %u, snapping!".format(url, res.status));
            try {
                js = await res.json();
                snap(state, js);
                return;
            } catch (e) {}
            if (snap) snap(res);
            else async_snap(res);
        }
    }
}


// DELETE wrapper
async function DELETE(url, callback, state, snap, json) {
    return GET(url, callback, state, snap, 'delete', JSON.stringify(json));
}

// POST wrapper
async function POST(url, callback, state, snap, json) {
    return GET(url, callback, state, snap, 'post', JSON.stringify(json));
}

// PUT wrapper
async function PUT(url, callback, state, snap, json) {
    return GET(url, callback, state, snap, 'put', JSON.stringify(json));
}

// PATCH wrapper
async function PATCH(url, callback, state, snap, json) {
    return GET(url, callback, state, snap, 'PATCH', JSON.stringify(json));
}

// whatwg fetch for IE
(function(self) {
  'use strict';

  if (self.fetch) {
    return
  }

  var support = {
    searchParams: 'URLSearchParams' in self,
    iterable: 'Symbol' in self && 'iterator' in Symbol,
    blob: 'FileReader' in self && 'Blob' in self && (function() {
      try {
        new Blob()
        return true
      } catch(e) {
        return false
      }
    })(),
    formData: 'FormData' in self,
    arrayBuffer: 'ArrayBuffer' in self
  }

  if (support.arrayBuffer) {
    var viewClasses = [
      '[object Int8Array]',
      '[object Uint8Array]',
      '[object Uint8ClampedArray]',
      '[object Int16Array]',
      '[object Uint16Array]',
      '[object Int32Array]',
      '[object Uint32Array]',
      '[object Float32Array]',
      '[object Float64Array]'
    ]

    var isDataView = function(obj) {
      return obj && DataView.prototype.isPrototypeOf(obj)
    }

    var isArrayBufferView = ArrayBuffer.isView || function(obj) {
      return obj && viewClasses.indexOf(Object.prototype.toString.call(obj)) > -1
    }
  }

  function normalizeName(name) {
    if (typeof name !== 'string') {
      name = String(name)
    }
    if (/[^a-z0-9\-#$%&'*+.\^_`|~]/i.test(name)) {
      throw new TypeError('Invalid character in header field name')
    }
    return name.toLowerCase()
  }

  function normalizeValue(value) {
    if (typeof value !== 'string') {
      value = String(value)
    }
    return value
  }

  // Build a destructive iterator for the value list
  function iteratorFor(items) {
    var iterator = {
      next: function() {
        var value = items.shift()
        return {done: value === undefined, value: value}
      }
    }

    if (support.iterable) {
      iterator[Symbol.iterator] = function() {
        return iterator
      }
    }

    return iterator
  }

  function Headers(headers) {
    this.map = {}

    if (headers instanceof Headers) {
      headers.forEach(function(value, name) {
        this.append(name, value)
      }, this)
    } else if (Array.isArray(headers)) {
      headers.forEach(function(header) {
        this.append(header[0], header[1])
      }, this)
    } else if (headers) {
      Object.getOwnPropertyNames(headers).forEach(function(name) {
        this.append(name, headers[name])
      }, this)
    }
  }

  Headers.prototype.append = function(name, value) {
    name = normalizeName(name)
    value = normalizeValue(value)
    var oldValue = this.map[name]
    this.map[name] = oldValue ? oldValue+','+value : value
  }

  Headers.prototype['delete'] = function(name) {
    delete this.map[normalizeName(name)]
  }

  Headers.prototype.get = function(name) {
    name = normalizeName(name)
    return this.has(name) ? this.map[name] : null
  }

  Headers.prototype.has = function(name) {
    return this.map.hasOwnProperty(normalizeName(name))
  }

  Headers.prototype.set = function(name, value) {
    this.map[normalizeName(name)] = normalizeValue(value)
  }

  Headers.prototype.forEach = function(callback, thisArg) {
    for (var name in this.map) {
      if (this.map.hasOwnProperty(name)) {
        callback.call(thisArg, this.map[name], name, this)
      }
    }
  }

  Headers.prototype.keys = function() {
    var items = []
    this.forEach(function(value, name) { items.push(name) })
    return iteratorFor(items)
  }

  Headers.prototype.values = function() {
    var items = []
    this.forEach(function(value) { items.push(value) })
    return iteratorFor(items)
  }

  Headers.prototype.entries = function() {
    var items = []
    this.forEach(function(value, name) { items.push([name, value]) })
    return iteratorFor(items)
  }

  if (support.iterable) {
    Headers.prototype[Symbol.iterator] = Headers.prototype.entries
  }

  function consumed(body) {
    if (body.bodyUsed) {
      return Promise.reject(new TypeError('Already read'))
    }
    body.bodyUsed = true
  }

  function fileReaderReady(reader) {
    return new Promise(function(resolve, reject) {
      reader.onload = function() {
        resolve(reader.result)
      }
      reader.onerror = function() {
        reject(reader.error)
      }
    })
  }

  function readBlobAsArrayBuffer(blob) {
    var reader = new FileReader()
    var promise = fileReaderReady(reader)
    reader.readAsArrayBuffer(blob)
    return promise
  }

  function readBlobAsText(blob) {
    var reader = new FileReader()
    var promise = fileReaderReady(reader)
    reader.readAsText(blob)
    return promise
  }

  function readArrayBufferAsText(buf) {
    var view = new Uint8Array(buf)
    var chars = new Array(view.length)

    for (var i = 0; i < view.length; i++) {
      chars[i] = String.fromCharCode(view[i])
    }
    return chars.join('')
  }

  function bufferClone(buf) {
    if (buf.slice) {
      return buf.slice(0)
    } else {
      var view = new Uint8Array(buf.byteLength)
      view.set(new Uint8Array(buf))
      return view.buffer
    }
  }

  function Body() {
    this.bodyUsed = false

    this._initBody = function(body) {
      this._bodyInit = body
      if (!body) {
        this._bodyText = ''
      } else if (typeof body === 'string') {
        this._bodyText = body
      } else if (support.blob && Blob.prototype.isPrototypeOf(body)) {
        this._bodyBlob = body
      } else if (support.formData && FormData.prototype.isPrototypeOf(body)) {
        this._bodyFormData = body
      } else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
        this._bodyText = body.toString()
      } else if (support.arrayBuffer && support.blob && isDataView(body)) {
        this._bodyArrayBuffer = bufferClone(body.buffer)
        // IE 10-11 can't handle a DataView body.
        this._bodyInit = new Blob([this._bodyArrayBuffer])
      } else if (support.arrayBuffer && (ArrayBuffer.prototype.isPrototypeOf(body) || isArrayBufferView(body))) {
        this._bodyArrayBuffer = bufferClone(body)
      } else {
        throw new Error('unsupported BodyInit type')
      }

      if (!this.headers.get('content-type')) {
        if (typeof body === 'string') {
          this.headers.set('content-type', 'text/plain;charset=UTF-8')
        } else if (this._bodyBlob && this._bodyBlob.type) {
          this.headers.set('content-type', this._bodyBlob.type)
        } else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
          this.headers.set('content-type', 'application/x-www-form-urlencoded;charset=UTF-8')
        }
      }
    }

    if (support.blob) {
      this.blob = function() {
        var rejected = consumed(this)
        if (rejected) {
          return rejected
        }

        if (this._bodyBlob) {
          return Promise.resolve(this._bodyBlob)
        } else if (this._bodyArrayBuffer) {
          return Promise.resolve(new Blob([this._bodyArrayBuffer]))
        } else if (this._bodyFormData) {
          throw new Error('could not read FormData body as blob')
        } else {
          return Promise.resolve(new Blob([this._bodyText]))
        }
      }

      this.arrayBuffer = function() {
        if (this._bodyArrayBuffer) {
          return consumed(this) || Promise.resolve(this._bodyArrayBuffer)
        } else {
          return this.blob().then(readBlobAsArrayBuffer)
        }
      }
    }

    this.text = function() {
      var rejected = consumed(this)
      if (rejected) {
        return rejected
      }

      if (this._bodyBlob) {
        return readBlobAsText(this._bodyBlob)
      } else if (this._bodyArrayBuffer) {
        return Promise.resolve(readArrayBufferAsText(this._bodyArrayBuffer))
      } else if (this._bodyFormData) {
        throw new Error('could not read FormData body as text')
      } else {
        return Promise.resolve(this._bodyText)
      }
    }

    if (support.formData) {
      this.formData = function() {
        return this.text().then(decode)
      }
    }

    this.json = function() {
      return this.text().then(JSON.parse)
    }

    return this
  }

  // HTTP methods whose capitalization should be normalized
  var methods = ['DELETE', 'GET', 'HEAD', 'OPTIONS', 'POST', 'PUT']

  function normalizeMethod(method) {
    var upcased = method.toUpperCase()
    return (methods.indexOf(upcased) > -1) ? upcased : method
  }

  function Request(input, options) {
    options = options || {}
    var body = options.body

    if (input instanceof Request) {
      if (input.bodyUsed) {
        throw new TypeError('Already read')
      }
      this.url = input.url
      this.credentials = input.credentials
      if (!options.headers) {
        this.headers = new Headers(input.headers)
      }
      this.method = input.method
      this.mode = input.mode
      if (!body && input._bodyInit != null) {
        body = input._bodyInit
        input.bodyUsed = true
      }
    } else {
      this.url = String(input)
    }

    this.credentials = options.credentials || this.credentials || 'omit'
    if (options.headers || !this.headers) {
      this.headers = new Headers(options.headers)
    }
    this.method = normalizeMethod(options.method || this.method || 'GET')
    this.mode = options.mode || this.mode || null
    this.referrer = null

    if ((this.method === 'GET' || this.method === 'HEAD') && body) {
      throw new TypeError('Body not allowed for GET or HEAD requests')
    }
    this._initBody(body)
  }

  Request.prototype.clone = function() {
    return new Request(this, { body: this._bodyInit })
  }

  function decode(body) {
    var form = new FormData()
    body.trim().split('&').forEach(function(bytes) {
      if (bytes) {
        var split = bytes.split('=')
        var name = split.shift().replace(/\+/g, ' ')
        var value = split.join('=').replace(/\+/g, ' ')
        form.append(decodeURIComponent(name), decodeURIComponent(value))
      }
    })
    return form
  }

  function parseHeaders(rawHeaders) {
    var headers = new Headers()
    // Replace instances of \r\n and \n followed by at least one space or horizontal tab with a space
    // https://tools.ietf.org/html/rfc7230#section-3.2
    var preProcessedHeaders = rawHeaders.replace(/\r?\n[\t ]+/g, ' ')
    preProcessedHeaders.split(/\r?\n/).forEach(function(line) {
      var parts = line.split(':')
      var key = parts.shift().trim()
      if (key) {
        var value = parts.join(':').trim()
        headers.append(key, value)
      }
    })
    return headers
  }

  Body.call(Request.prototype)

  function Response(bodyInit, options) {
    if (!options) {
      options = {}
    }

    this.type = 'default'
    this.status = options.status === undefined ? 200 : options.status
    this.ok = this.status >= 200 && this.status < 300
    this.statusText = 'statusText' in options ? options.statusText : 'OK'
    this.headers = new Headers(options.headers)
    this.url = options.url || ''
    this._initBody(bodyInit)
  }

  Body.call(Response.prototype)

  Response.prototype.clone = function() {
    return new Response(this._bodyInit, {
      status: this.status,
      statusText: this.statusText,
      headers: new Headers(this.headers),
      url: this.url
    })
  }

  Response.error = function() {
    var response = new Response(null, {status: 0, statusText: ''})
    response.type = 'error'
    return response
  }

  var redirectStatuses = [301, 302, 303, 307, 308]

  Response.redirect = function(url, status) {
    if (redirectStatuses.indexOf(status) === -1) {
      throw new RangeError('Invalid status code')
    }

    return new Response(null, {status: status, headers: {location: url}})
  }

  self.Headers = Headers
  self.Request = Request
  self.Response = Response

  self.fetch = function(input, init) {
    return new Promise(function(resolve, reject) {
      var request = new Request(input, init)
      var xhr = new XMLHttpRequest()

      xhr.onload = function() {
        var options = {
          status: xhr.status,
          statusText: xhr.statusText,
          headers: parseHeaders(xhr.getAllResponseHeaders() || '')
        }
        options.url = 'responseURL' in xhr ? xhr.responseURL : options.headers.get('X-Request-URL')
        var body = 'response' in xhr ? xhr.response : xhr.responseText
        resolve(new Response(body, options))
      }

      xhr.onerror = function() {
        reject(new TypeError('Network request failed'))
      }

      xhr.ontimeout = function() {
        reject(new TypeError('Network request failed'))
      }

      xhr.open(request.method, request.url, true)

      if (request.credentials === 'include') {
        xhr.withCredentials = true
      } else if (request.credentials === 'omit') {
        xhr.withCredentials = false
      }

      if ('responseType' in xhr && support.blob) {
        xhr.responseType = 'blob'
      }

      request.headers.forEach(function(value, name) {
        xhr.setRequestHeader(name, value)
      })

      xhr.send(typeof request._bodyInit === 'undefined' ? null : request._bodyInit)
    })
  }
  self.fetch.polyfill = true
})(typeof self !== 'undefined' ? self : this);