shaka-player
Version:
DASH/EME video player library
361 lines (322 loc) • 12.5 kB
JavaScript
/*! @license
* Shaka Player
* Copyright 2016 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
goog.provide('shaka.net.HttpFetchPlugin');
goog.require('goog.asserts');
goog.require('shaka.log');
goog.require('shaka.net.HttpPluginUtils');
goog.require('shaka.net.NetworkingEngine');
goog.require('shaka.util.AbortableOperation');
goog.require('shaka.util.Error');
goog.require('shaka.util.MapUtils');
goog.require('shaka.util.Timer');
/**
* @summary A networking plugin to handle http and https URIs via the Fetch API.
* @export
*/
shaka.net.HttpFetchPlugin = class {
/**
* @param {string} uri
* @param {shaka.extern.Request} request
* @param {shaka.net.NetworkingEngine.RequestType} requestType
* @param {shaka.extern.ProgressUpdated} progressUpdated Called when a
* progress event happened.
* @param {shaka.extern.HeadersReceived} headersReceived Called when the
* headers for the download are received, but before the body is.
* @param {shaka.extern.SchemePluginConfig} config
* @return {!shaka.extern.IAbortableOperation.<shaka.extern.Response>}
* @export
*/
static parse(uri, request, requestType, progressUpdated, headersReceived,
config) {
const headers = new shaka.net.HttpFetchPlugin.Headers_();
shaka.util.MapUtils.asMap(request.headers).forEach((value, key) => {
headers.append(key, value);
});
const controller = new shaka.net.HttpFetchPlugin.AbortController_();
/** @type {!RequestInit} */
const init = {
// Edge does not treat null as undefined for body; https://bit.ly/2luyE6x
body: request.body || undefined,
headers: headers,
method: request.method,
signal: controller.signal,
credentials: request.allowCrossSiteCredentials ? 'include' : undefined,
};
/** @type {shaka.net.HttpFetchPlugin.AbortStatus} */
const abortStatus = {
canceled: false,
timedOut: false,
};
const minBytes = config.minBytesForProgressEvents || 0;
const pendingRequest = shaka.net.HttpFetchPlugin.request_(
uri, request, requestType, init, abortStatus, progressUpdated,
headersReceived, request.streamDataCallback, minBytes);
/** @type {!shaka.util.AbortableOperation} */
const op = new shaka.util.AbortableOperation(pendingRequest, () => {
abortStatus.canceled = true;
controller.abort();
return Promise.resolve();
});
// The fetch API does not timeout natively, so do a timeout manually using
// the AbortController.
const timeoutMs = request.retryParameters.timeout;
if (timeoutMs) {
const timer = new shaka.util.Timer(() => {
abortStatus.timedOut = true;
controller.abort();
});
timer.tickAfter(timeoutMs / 1000);
// To avoid calling |abort| on the network request after it finished, we
// will stop the timer when the requests resolves/rejects.
op.finally(() => {
timer.stop();
});
}
return op;
}
/**
* @param {string} uri
* @param {shaka.extern.Request} request
* @param {shaka.net.NetworkingEngine.RequestType} requestType
* @param {!RequestInit} init
* @param {shaka.net.HttpFetchPlugin.AbortStatus} abortStatus
* @param {shaka.extern.ProgressUpdated} progressUpdated
* @param {shaka.extern.HeadersReceived} headersReceived
* @param {?function(BufferSource):!Promise} streamDataCallback
* @param {number} minBytes
* @return {!Promise<!shaka.extern.Response>}
* @private
*/
static async request_(uri, request, requestType, init, abortStatus,
progressUpdated, headersReceived, streamDataCallback, minBytes) {
const fetch = shaka.net.HttpFetchPlugin.fetch_;
const ReadableStream = shaka.net.HttpFetchPlugin.ReadableStream_;
let response;
let arrayBuffer = new ArrayBuffer(0);
let loaded = 0;
let lastLoaded = 0;
// Last time stamp when we got a progress event.
let lastTime = Date.now();
try {
// The promise returned by fetch resolves as soon as the HTTP response
// headers are available. The download itself isn't done until the promise
// for retrieving the data (arrayBuffer, blob, etc) has resolved.
response = await fetch(uri, init);
// At this point in the process, we have the headers of the response, but
// not the body yet.
headersReceived(shaka.net.HttpFetchPlugin.headersToGenericObject_(
response.headers));
// In new versions of Chromium, HEAD requests now have a response body
// that is null.
// So just don't try to download the body at all, if it's a HEAD request,
// to avoid null reference errors.
// See: https://crbug.com/1297060
if (init.method != 'HEAD') {
goog.asserts.assert(response.body,
'non-HEAD responses should have a body');
const contentLengthRaw = response.headers.get('Content-Length');
const contentLength =
contentLengthRaw ? parseInt(contentLengthRaw, 10) : 0;
// Fetch returning a ReadableStream response body is not currently
// supported by all browsers.
// Browser compatibility:
// https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API
// If it is not supported, returning the whole segment when
// it's ready (as xhr)
if (!response.body) {
arrayBuffer = await response.arrayBuffer();
const currentTime = Date.now();
// If the time between last time and this time we got progress event
// is long enough, or if a whole segment is downloaded, call
// progressUpdated().
progressUpdated(currentTime - lastTime, arrayBuffer.byteLength, 0);
} else {
// Getting the reader in this way allows us to observe the process of
// downloading the body, instead of just waiting for an opaque
// promise to resolve.
// We first clone the response because calling getReader lock the body
// stream; if we didn't clone it here, we would be unable to get the
// response's arrayBuffer later.
const reader = response.clone().body.getReader();
const start = (controller) => {
const push = async () => {
let readObj;
try {
readObj = await reader.read();
} catch (e) {
// If we abort the request, we'll get an error here.
// Just ignore it
// since real errors will be reported when we read
// the buffer below.
shaka.log.v1('error reading from stream', e.message);
return;
}
if (!readObj.done) {
loaded += readObj.value.byteLength;
if (streamDataCallback) {
await streamDataCallback(readObj.value);
}
}
const currentTime = Date.now();
const chunkSize = loaded - lastLoaded;
// If the time between last time and this time we got
// progress event is long enough, or if a whole segment
// is downloaded, call progressUpdated().
if ((currentTime - lastTime > 100 && chunkSize >= minBytes) ||
readObj.done) {
const numBytesRemaining =
readObj.done ? 0 : contentLength - loaded;
progressUpdated(currentTime - lastTime, chunkSize,
numBytesRemaining);
lastLoaded = loaded;
lastTime = currentTime;
}
if (readObj.done) {
goog.asserts.assert(!readObj.value,
'readObj should be unset when "done" is true.');
controller.close();
} else {
controller.enqueue(readObj.value);
push();
}
};
push();
};
// Create a ReadableStream to use the reader. We don't need to use the
// actual stream for anything, though, as we are using the response's
// arrayBuffer method to get the body, so we don't store the
// ReadableStream.
new ReadableStream({start}); // eslint-disable-line no-new
arrayBuffer = await response.arrayBuffer();
}
}
} catch (error) {
if (abortStatus.canceled) {
throw new shaka.util.Error(
shaka.util.Error.Severity.RECOVERABLE,
shaka.util.Error.Category.NETWORK,
shaka.util.Error.Code.OPERATION_ABORTED,
uri, requestType);
} else if (abortStatus.timedOut) {
throw new shaka.util.Error(
shaka.util.Error.Severity.RECOVERABLE,
shaka.util.Error.Category.NETWORK,
shaka.util.Error.Code.TIMEOUT,
uri, requestType);
} else {
throw new shaka.util.Error(
shaka.util.Error.Severity.RECOVERABLE,
shaka.util.Error.Category.NETWORK,
shaka.util.Error.Code.HTTP_ERROR,
uri, error, requestType);
}
}
const headers = shaka.net.HttpFetchPlugin.headersToGenericObject_(
response.headers);
return shaka.net.HttpPluginUtils.makeResponse(headers, arrayBuffer,
response.status, uri, response.url, request, requestType);
}
/**
* @param {!Headers} headers
* @return {!Object<string, string>}
* @private
*/
static headersToGenericObject_(headers) {
const headersObj = {};
headers.forEach((value, key) => {
// Since Edge incorrectly return the header with a leading new line
// character ('\n'), we trim the header here.
headersObj[key.trim()] = value;
});
return headersObj;
}
/**
* Determine if the Fetch API is supported in the browser. Note: this is
* deliberately exposed as a method to allow the client app to use the same
* logic as Shaka when determining support.
* @return {boolean}
* @export
*/
static isSupported() {
// On Edge, ReadableStream exists, but attempting to construct it results in
// an error. See https://bit.ly/2zwaFLL
// So this has to check that ReadableStream is present AND usable.
if (window.ReadableStream) {
try {
new ReadableStream({}); // eslint-disable-line no-new
} catch (e) {
return false;
}
} else {
return false;
}
// Old fetch implementations hasn't body and ReadableStream implementation
// See: https://github.com/shaka-project/shaka-player/issues/5088
if (window.Response) {
const response = new Response('');
if (!response.body) {
return false;
}
} else {
return false;
}
return !!(window.fetch && !('polyfill' in window.fetch) &&
window.AbortController);
}
};
/**
* @typedef {{
* canceled: boolean,
* timedOut: boolean
* }}
* @property {boolean} canceled
* Indicates if the request was canceled.
* @property {boolean} timedOut
* Indicates if the request timed out.
*/
shaka.net.HttpFetchPlugin.AbortStatus;
/**
* Overridden in unit tests, but compiled out in production.
*
* @const {function(string, !RequestInit)}
* @private
*/
shaka.net.HttpFetchPlugin.fetch_ = window.fetch;
/**
* Overridden in unit tests, but compiled out in production.
*
* @const {function(new: AbortController)}
* @private
*/
shaka.net.HttpFetchPlugin.AbortController_ = window.AbortController;
/**
* Overridden in unit tests, but compiled out in production.
*
* @const {function(new: ReadableStream, !Object)}
* @private
*/
shaka.net.HttpFetchPlugin.ReadableStream_ = window.ReadableStream;
/**
* Overridden in unit tests, but compiled out in production.
*
* @const {function(new: Headers)}
* @private
*/
shaka.net.HttpFetchPlugin.Headers_ = window.Headers;
if (shaka.net.HttpFetchPlugin.isSupported()) {
shaka.net.NetworkingEngine.registerScheme(
'http', shaka.net.HttpFetchPlugin.parse,
shaka.net.NetworkingEngine.PluginPriority.PREFERRED,
/* progressSupport= */ true);
shaka.net.NetworkingEngine.registerScheme(
'https', shaka.net.HttpFetchPlugin.parse,
shaka.net.NetworkingEngine.PluginPriority.PREFERRED,
/* progressSupport= */ true);
shaka.net.NetworkingEngine.registerScheme(
'blob', shaka.net.HttpFetchPlugin.parse,
shaka.net.NetworkingEngine.PluginPriority.PREFERRED,
/* progressSupport= */ true);
}