webrtc-adapter
Version:
A shim to insulate apps from WebRTC spec changes and browser prefix differences
236 lines (224 loc) • 8.51 kB
JavaScript
/*
* Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree.
*/
/* eslint-env node */
;
var utils = require('../utils.js');
var logging = utils.log;
// Expose public methods.
module.exports = function(window) {
var browserDetails = utils.detectBrowser(window);
var navigator = window && window.navigator;
var constraintsToChrome_ = function(c) {
if (typeof c !== 'object' || c.mandatory || c.optional) {
return c;
}
var cc = {};
Object.keys(c).forEach(function(key) {
if (key === 'require' || key === 'advanced' || key === 'mediaSource') {
return;
}
var r = (typeof c[key] === 'object') ? c[key] : {ideal: c[key]};
if (r.exact !== undefined && typeof r.exact === 'number') {
r.min = r.max = r.exact;
}
var oldname_ = function(prefix, name) {
if (prefix) {
return prefix + name.charAt(0).toUpperCase() + name.slice(1);
}
return (name === 'deviceId') ? 'sourceId' : name;
};
if (r.ideal !== undefined) {
cc.optional = cc.optional || [];
var oc = {};
if (typeof r.ideal === 'number') {
oc[oldname_('min', key)] = r.ideal;
cc.optional.push(oc);
oc = {};
oc[oldname_('max', key)] = r.ideal;
cc.optional.push(oc);
} else {
oc[oldname_('', key)] = r.ideal;
cc.optional.push(oc);
}
}
if (r.exact !== undefined && typeof r.exact !== 'number') {
cc.mandatory = cc.mandatory || {};
cc.mandatory[oldname_('', key)] = r.exact;
} else {
['min', 'max'].forEach(function(mix) {
if (r[mix] !== undefined) {
cc.mandatory = cc.mandatory || {};
cc.mandatory[oldname_(mix, key)] = r[mix];
}
});
}
});
if (c.advanced) {
cc.optional = (cc.optional || []).concat(c.advanced);
}
return cc;
};
var shimConstraints_ = function(constraints, func) {
constraints = JSON.parse(JSON.stringify(constraints));
if (constraints && typeof constraints.audio === 'object') {
var remap = function(obj, a, b) {
if (a in obj && !(b in obj)) {
obj[b] = obj[a];
delete obj[a];
}
};
constraints = JSON.parse(JSON.stringify(constraints));
remap(constraints.audio, 'autoGainControl', 'googAutoGainControl');
remap(constraints.audio, 'noiseSuppression', 'googNoiseSuppression');
constraints.audio = constraintsToChrome_(constraints.audio);
}
if (constraints && typeof constraints.video === 'object') {
// Shim facingMode for mobile & surface pro.
var face = constraints.video.facingMode;
face = face && ((typeof face === 'object') ? face : {ideal: face});
var getSupportedFacingModeLies = browserDetails.version < 61;
if ((face && (face.exact === 'user' || face.exact === 'environment' ||
face.ideal === 'user' || face.ideal === 'environment')) &&
!(navigator.mediaDevices.getSupportedConstraints &&
navigator.mediaDevices.getSupportedConstraints().facingMode &&
!getSupportedFacingModeLies)) {
delete constraints.video.facingMode;
var matches;
if (face.exact === 'environment' || face.ideal === 'environment') {
matches = ['back', 'rear'];
} else if (face.exact === 'user' || face.ideal === 'user') {
matches = ['front'];
}
if (matches) {
// Look for matches in label, or use last cam for back (typical).
return navigator.mediaDevices.enumerateDevices()
.then(function(devices) {
devices = devices.filter(function(d) {
return d.kind === 'videoinput';
});
var dev = devices.find(function(d) {
return matches.some(function(match) {
return d.label.toLowerCase().indexOf(match) !== -1;
});
});
if (!dev && devices.length && matches.indexOf('back') !== -1) {
dev = devices[devices.length - 1]; // more likely the back cam
}
if (dev) {
constraints.video.deviceId = face.exact ? {exact: dev.deviceId} :
{ideal: dev.deviceId};
}
constraints.video = constraintsToChrome_(constraints.video);
logging('chrome: ' + JSON.stringify(constraints));
return func(constraints);
});
}
}
constraints.video = constraintsToChrome_(constraints.video);
}
logging('chrome: ' + JSON.stringify(constraints));
return func(constraints);
};
var shimError_ = function(e) {
return {
name: {
PermissionDeniedError: 'NotAllowedError',
InvalidStateError: 'NotReadableError',
DevicesNotFoundError: 'NotFoundError',
ConstraintNotSatisfiedError: 'OverconstrainedError',
TrackStartError: 'NotReadableError',
MediaDeviceFailedDueToShutdown: 'NotReadableError',
MediaDeviceKillSwitchOn: 'NotReadableError'
}[e.name] || e.name,
message: e.message,
constraint: e.constraintName,
toString: function() {
return this.name + (this.message && ': ') + this.message;
}
};
};
var getUserMedia_ = function(constraints, onSuccess, onError) {
shimConstraints_(constraints, function(c) {
navigator.webkitGetUserMedia(c, onSuccess, function(e) {
onError(shimError_(e));
});
});
};
navigator.getUserMedia = getUserMedia_;
// Returns the result of getUserMedia as a Promise.
var getUserMediaPromise_ = function(constraints) {
return new Promise(function(resolve, reject) {
navigator.getUserMedia(constraints, resolve, reject);
});
};
if (!navigator.mediaDevices) {
navigator.mediaDevices = {
getUserMedia: getUserMediaPromise_,
enumerateDevices: function() {
return new Promise(function(resolve) {
var kinds = {audio: 'audioinput', video: 'videoinput'};
return window.MediaStreamTrack.getSources(function(devices) {
resolve(devices.map(function(device) {
return {label: device.label,
kind: kinds[device.kind],
deviceId: device.id,
groupId: ''};
}));
});
});
},
getSupportedConstraints: function() {
return {
deviceId: true, echoCancellation: true, facingMode: true,
frameRate: true, height: true, width: true
};
}
};
}
// A shim for getUserMedia method on the mediaDevices object.
// TODO(KaptenJansson) remove once implemented in Chrome stable.
if (!navigator.mediaDevices.getUserMedia) {
navigator.mediaDevices.getUserMedia = function(constraints) {
return getUserMediaPromise_(constraints);
};
} else {
// Even though Chrome 45 has navigator.mediaDevices and a getUserMedia
// function which returns a Promise, it does not accept spec-style
// constraints.
var origGetUserMedia = navigator.mediaDevices.getUserMedia.
bind(navigator.mediaDevices);
navigator.mediaDevices.getUserMedia = function(cs) {
return shimConstraints_(cs, function(c) {
return origGetUserMedia(c).then(function(stream) {
if (c.audio && !stream.getAudioTracks().length ||
c.video && !stream.getVideoTracks().length) {
stream.getTracks().forEach(function(track) {
track.stop();
});
throw new DOMException('', 'NotFoundError');
}
return stream;
}, function(e) {
return Promise.reject(shimError_(e));
});
});
};
}
// Dummy devicechange event methods.
// TODO(KaptenJansson) remove once implemented in Chrome stable.
if (typeof navigator.mediaDevices.addEventListener === 'undefined') {
navigator.mediaDevices.addEventListener = function() {
logging('Dummy mediaDevices.addEventListener called.');
};
}
if (typeof navigator.mediaDevices.removeEventListener === 'undefined') {
navigator.mediaDevices.removeEventListener = function() {
logging('Dummy mediaDevices.removeEventListener called.');
};
}
};