OpenTok Network Test
This Node module lets you check network connectivity to resources and services required
to use OpenTok. Run this on a web client to get the following information:
-
Whether the client will be able to succeed in connecting to an OpenTok session
-
MOS estimates for the audio and video quality
the client will experience
-
A recommended frame rate and resolution to use for publishing to a session
For a sample that uses this module, see the OpenTok Pre-call Test
tool.
Example Usage in Node/Browserify/Webpack
First, install the package:
$ npm install opentok-network-test-js
Now load the OpenTok Network Test in your project. The module exports two objects:
Using CommonJS:
const NetworkTest = require('opentok-network-test-js').default;
const ErrorNames = require('opentok-network-test-js').ErrorNames;
... or ES6 ...
import NetworkTest, { ErrorNames } from 'opentok-network-test-js';
Load the OpenTok.js library.
Instantiate an instance of the test object, passing in the OpenTok.js OT object and
a configuration object. The configuration object contains an API key for your app's
OpenTok project, a session ID for a test session, and a token for that session:
const otNetworkTest = new NetworkTest(OT, {
apiKey: '123456',
sessionId: '1_MX40NzIwMzJ-fjE1MDElGQkJJfn4',
token: 'T1==cGFydG5lcXN0PQ=='
});
Use the OpenTok server SDKs to generate a
unique session ID for each client. This session ID is used for the network test, and it must
be different than the session ID used for communication in the app. The test session must be
a routed session -- one that uses the OpenTok Media
Router. Also generate a test
token that has publish privileges.
Then run the test methods:
otNetworkTest.testConnectivity().then((results) => {
console.log('OpenTok connectivity test results', results);
otNetworkTest.testQuality(function updateCallback(stats) {
console.log('intermediate testQuality stats', stats);
}).then((results) => {
console.log('OpenTok quality results', results);
let publisherSettings = {};
if (results.video.reason) {
console.log('Video not supported:', results.video.reason);
publisherSettings.videoSource = null;
} else {
publisherSettings.frameRate = results.video.recommendedFrameRate;
publisherSettings.resolution = results.video.recommendedResolution;
}
if (!results.audio.supported) {
console.log('Audio not supported:', results.audio.reason);
publisherSettings.audioSource = null;
}
if (!publisherSettings.videoSource && !publisherSettings.audioSource) {
} else {
}
}).catch((error) => {
console.log('OpenTok quality test error', error);
});
}).catch(function(error) {
console.log('OpenTok connectivity test error', error);
});
You can also run the tests in audio-only mode by passing in an options
object
with audioOnly
set to true
into the constructor:
const sessionInfo = {
apiKey: '123456',
sessionId: '1_MX40NzIwMzJ-fjE1MDElGQkJJfn4',
token: 'T1==cGFydG5lcXN0PQ=='
}
const options = {audioOnly: true};
const otNetworkTest = new NetworkTest(OT, sessionInfo, options);
otNetworkTest.testQuality(function updateCallback(stats) {
const currentStats = stats[stats.length - 1];
console.log('testQuality stats', currentStats);
}).then((results) => {
console.log('OpenTok quality results', results);
}).catch((error) => {
console.log('OpenTok quality test error', error);
});
This code uses Promises returned by the OTNetworkTest.testConnectivity()
and OTNetworkTest.testQuality()
methods. Alternatively, you can pass completion
handler functions into each of these methods.
See the following section for details on using the test results.
See the /sample subdirectory (and the /sample/README.md file) for a sample app.
Supported browsers
The OTNetworkTest.testConnectivity()
method is supported in Chrome, Firefox, Safari,
Opera, and Edge.
The OTNetworkTest.testQuality()
method is supported in Chrome, Firefox, Safari,
Opera, and Chromium-based versions of Edge (versions 79+).
It is not supported in non-Chromium-based versions of Edge.
API reference
The OTNetworkTest NPM module includes three public methods:
-
The OTNetworkTest() constructor method
-
The OTNetworkTest.testConnectivity()
method
-
The OTNetworkTest.testQuality()
method
Note: Some API changes were introduced in v2. See the
releases page for details.
OTNetworkTest() constructor
The OTNetworkTest()
constructor includes the following parameters:
-
ot
-- A reference to the OpenTok.js OT
object. You must load OpenTok.js into the
web page and pass the OpenTok.js OT
into the OTNetworkTest()
constructor.
Note that you may load OpenTok.js from the opentok.com server
(https://static.opentok.com/v2/js/opentok.js) or via NPM
(https://www.npmjs.com/package/@opentok/client). Or if your OpenTok project uses the enterprise
environment,
you will load OpenTok.js from the enterprise URL.
Passing the OT object into the OTNetworkTest()
constructor ensures that the tests will
use the same version of OpenTok and the same OpenTok environment that will be used by the
main OpenTok session in your application.
-
sessionInfo
-- An object containing the following:
-
apiKey
-- The API key corresponding to the OpenTok project the app uses.
-
sessionId
-- A test session ID. This must be an ID for a different session than
the one that your application will be used for communication. Generate a unique
session ID for each client. This session ID is used for the network test, and it
must be different than the session ID used for communication in the app.
The test session must be a routed session -- one that uses the OpenTok Media
Router.
To test connectivity
in a specific region, specify a location hint when creating the test
session.
-
token
-- A token corresponding to the test session. The role of the token must be
either publisher
or moderator
.
The sessionInfo
parameter is required.
-
options
--The options
parameter is an object containing the following properties,
each of which are optional:
audioOnly
(Boolean) -- Set this property to true
to run audio-only tests.
When this option is set to false
(the default), the quality test will try to run
an audio-video quality test (using both the camera and microphone). If there is no
camera available, or if the results of the audio-video test do not support adequate
audio quality, the test continues in audio-only mode.
Setting the audioOnly
to true
will reduce the time of the quality test on systems that
have both a microphone and camera attached (since the audio-only test is shorter than the audio-video test).
-
timeout
(Number) -- Set this property to the maximum duration of the testQuality()
test, in milliseconds. Set this to a value greater than 5000 (5 seconds) but less than
30000 (30 seconds). (Values outside of this range are ignored.) If you do not set this value,
the testQuality()
test will run for approximately 30 seconds for an audio-video test or for 10 seconds for an audio-only test.
The timeout period begins when the quality test starts publishing (after the user grants
access to the camera and microphone).
Setting a lower timeout duration may result in less accurate results, including MOS ratings.
-
audioSource
(String) -- The ID of the audio input device (such as a microphone)
to be used by the test publisher. You can obtain a list of available devices,
including audio input devices, by calling the OT.getDevices()
method.
You may want to set this to have the OpenTok Network Test use the same device that
will be used in the real OpenTok session. This way, the test prompts the end user
to grant permission to the correct device. Note that changing the audio device may not
influence the quality test score.
-
videoSource
(String) -- The ID of the video input device (such as a camera)
to be used by the test publisher. You can obtain a list of available devices,
including audio input devices, by calling the OT.getDevices()
method.
You may want to set this to have the OpenTok Network Test use the same device that
will be used in the real OpenTok session. This way, the test prompts the end user
to grant permission to the correct device. Note that changing the video device may not
influence the quality test score.
-
initSessionOptions
(Object) -- An object that includes optional options
for initializing the session
(Session Options).
This object includes the following properties:
ipWhitelist
(Boolean) -- This is available as an add-on feature
for enterprise accounts. Set this to true if IP white listing
is enabled for your project. The default value is false.iceConfig
(Object) -- This feature is part of the configurable TURN add-on feature.
-
proxyServerUrl
(String) -- (Optional) Set this to the proxy server URL
you use in the OpenTok client SDKs (for example, when calling OT.setProxyUrl()
in OpenTok.js). For more information, please check the
IP Proxy Documentation.
-
scalableVideo
(Boolean) -- (Optional) Whether to use
scalable video
(true
) or not (false
, the default). Disabling scalable video
was added in OpenTok.js version 2.24.7.
The options
parameter is optional.
The constructor throws an Error object with a message
property and a name
property. The
message property describes the error. You should check the name
property to determine the
type of error. The name
property will be set to one of the values defined as properties of
the ErrorNames
object (see ErrorNames). For example:
try {
const otNetworkTest = new NetworkTest(OT, sessionInfo);
} catch (error) {
switch (error.name) {
case ErrorNames.MISSING_OPENTOK_INSTANCE:
console.error('Missing OT instance in constructor.');
break;
case ErrorNames.INCOMPLETE_SESSON_CREDENTIALS:
case ErrorNames.MISSING_SESSON_CREDENTIALS:
case ErrorNames.INVALID_SESSON_CREDENTIALS:
console.error('Missing or invalid OpenTok session credentials.');
break;
default:
console.error('Unknown error .');
}
}
OTNetworkTest.testConnectivity()
This method checks to see if the client can connect to OpenTok servers. The method returns
a Promise that is resolved when the connectivity check completes. The promise is resolved
with a results
object that has the following two properties:
-
success
(Boolean) -- true
if connectivity to OpenTok servers succeeded; false
if
any connectivity test failed.
-
failedTests
(Array) -- If connectivity failed, this array contains an object for each
failure type. The object has two properties, type
and errors
:
-
type
-- A sting defining the failure type. It will be set to one of the following values:
-
'api'
-- The test could not connect to the OpenTok API server. Connection to this
server is required to connect to an OpenTok session.
-
'messaging'
-- The test could not establish a connection to the OpenTok messaging WebSocket.
This connection is required to connect to an OpenTok session. In addition to other causes
for WebSocket connectivity failures, this failure type will occur if you pass an invalid
OpenTok API key, session ID, or token into the OTNetworkTest()
constructor.
-
'media'
-- The test could not connect to the OpenTok Media Router. If your app uses
a routed session, it will not succeed in using OpenTok. However, if your app uses
a relayed session, the client may still succeed in using the OpenTok session, although
it may fail if the relayed session requires use of a TURN server.
-
'logging'
-- The test could not connect to the OpenTok logging server. The OpenTok.js
library periodically logs data (such as video and audio quality) to this server. The client
can still connect to an OpenTok session, however TokBox will not collect data that may help
you debug issues with the session, using tools like OpenTok
Inspector.
-
error
-- An object defining the reason for the type of failure. This object includes
a message
property and a name
property. The message property describes the error.
You should check the name
property to determine the type of error. The name
property
will be set to one of the values defined as properties of the ErrorNames
object (see ErrorNames):
For example:
otNetworkTest.testConnectivity(function(results) {
results.failedTests && results.failedTests.forEach(result) => {
switch (failedTest.error.name) {
case ErrorNames.FAILED_TO_OBTAIN_MEDIA_DEVICES:
break;
case ErrorNames.NO_AUDIO_CAPTURE_DEVICES:
case ErrorNames.NO_VIDEO_CAPTURE_DEVICES:
break;
default:
console.error('Unknown error .');
}
}
});
If all connectivity tests succeed, the failedTests
property is undefined.
OTNetworkTest.testQuality(updateCallback)
This function runs a test publisher (using the API key, session ID and token provided in the constructor). Based on the measured video bitrate, audio bitrate, and the audio packet loss for
the published stream, it provides the following results:
-
Whether audio and video are supported and a reason why they aren't supported (if they aren't).
-
The MOS estimate (from 0 - 4.5) for the the audio and video published by the client.
-
Statistics for the test, including bitrate and packet loss ratio (for both audio and video),
as well as the video packet loss ratio.
-
The recommended supported publisher settings. These settings include the recommended video
frame rate and resolution for a stream published by the client. Or, if the stats do not support
video, the results indicate whether an audio-only published is recommended or not, based on the
measured audio bitrate and packet loss.
This method takes one parameter: updateCallback
. The method returns a Promise.
updateCallback
The updateCallback
function is called periodically during the test (at a 1-second test interval).
The object passed into the updateCallback
function includes statistics about the audio and
video in the test stream. The object has the following data:
{
audio: {
timestamp: 1509747314,
bytesReceived: 434349, // The total number of audio bytes received, cumulative
packetsReceived: 24234, // The total number of audio packets received, cumulative
packetsLost: 0 // The total number of audio packets lost, cumulative
},
video: {
timestamp: 1509747314,
bytesReceived: 434349, // The total number of video bytes received, cumulative
frameRate: 15, // The video frame rate
packetsReceived: 24234, // The total number of video packets received, cumulative
packetsLost: 0 // The total number of video packets lost, cumulative
},
timestamp: 1512679143897, // The timestamp of the sample
phase: 'audio-video' // Either 'audio-video' or 'audio-only'
}
The phase
property is set to 'audio-video' during the initial audio-video test. If a
secondary audio-only test is required (because audio quality was not acceptable during the
audio-video test), the property is set to 'audio-only'.
Pass in a null
value if you do not want to register an updateCallback
function.
Promise returned
The Promise returned by the OTNetworkTest.testQuality()
method is resolved when
the connectivity check completes. The promise is resolved with a results
object that has the
following properties:
results
is undefined if there was an error in running the tests (and the error
parameter
is unset).
Important: v1 included a results.mos
property (an overall MOS rating for the test). This
was removed in v2 and replaced with results.audio.mos
and results.video.mos
properties.
The results, including the MOS estimates and the recommended video resolution and frame rate are
subjective. You can adjust the values used in the source code, or you can use the data passed into
the updateCallback()
function and apply your own quality analysis algorithm.
The Promise returned by the OTNetworkTest.testQuality()
method is rejected when the connectivity
check encounters an error. The promise is reject with an error
object that has two properties:
a message
property and a name
property. The message property describes the error.
You should check the name
property to determine the type of error. The name
property
will be set to one of the values defined as properties of the ErrorNames
object
(see Error.name values).
otNetworkTest.testQuality(null, function updateCallback() {
}).then((results) => {
}).catch((error) => {
switch (error.name) {
case ErrorNames.UNSUPPORTED_BROWSER:
break;
case ErrorNames.CONNECT_TO_SESSION_NETWORK_ERROR:
break;
case ErrorNames.FAILED_TO_OBTAIN_MEDIA_DEVICES:
break;
case ErrorNames.NO_AUDIO_CAPTURE_DEVICES:
case ErrorNames.NO_VIDEO_CAPTURE_DEVICES:
break;
default:
console.error('Unknown error .');
}
});
OTNetworkTest.stop()
Stops the testConnectivity()
test if it is running. The test will not stop until it has been
running for at least 5 seconds (after the user has granted access to the camera and microphone).
While you can call stop()
prior to this, results will not be returned until the 5-second mark.
ErrorNames
The ErrorNames object includes properties that enumerate values used in the
name
property of OTNetworkTest error objects. You should check the name
property of
an error object (against the values defined in ErrorNames) to determine the type of error.
Errors thrown by the OTNetworkTest() constructor
Error.name property set to this property of ErrorNames ... | Description |
---|
MISSING_OPENTOK_INSTANCE | An instance of OT, the OpenTok.js client SDK, was not passed into the constructor. |
INCOMPLETE_SESSON_CREDENTIALS | The sessionInfo object passed into the constructor did not include an apiKey , sessionId , or token object. |
MISSING_SESSON_CREDENTIALS | No sessionInfo object was passed into the constructor. |
testConnectivity() errors
The testConnectivity()
returns a JavaScript promise that succeeds with a results
object.
The results
object contains a failedTests
array, and each element of this array (if there are
any elements) has an error
property, which is error object has a name
property set to one of
the following:
Error.name property set to this property of ErrorNames ... | Description |
---|
API_CONNECTIVITY_ERROR | The test failed to connect to OpenTOK API Server. |
CONNECT_TO_SESSION_ERROR | The test failed to connect to the test OpenTok session due to a network error. |
CONNECT_TO_SESSION_TOKEN_ERROR | The test failed to connect to the test OpenTok session due to an invalid token. |
CONNECT_TO_SESSION_ID_ERROR | The test failed to connect to the test OpenTok session due to an invalid session ID. |
CONNECT_TO_SESSION_NETWORK_ERROR | The test failed to connect to the test OpenTok session due to a network error. |
FAILED_TO_OBTAIN_MEDIA_DEVICES | The test failed to obtain media devices (a camera or microphone). |
NO_AUDIO_CAPTURE_DEVICES | The browser cannot access a microphone. |
NO_VIDEO_CAPTURE_DEVICES | The browser cannot access a camera. |
PUBLISH_TO_SESSION_ERROR | Encountered an unknown error while attempting to publish to a session. |
FAILED_MESSAGING_SERVER_TEST | The test failed to connect to media server due to messaging server connection failure. |
FAILED_TO_CREATE_LOCAL_PUBLISHER | The test failed to create a local publisher object. |
PUBLISH_TO_SESSION_NOT_CONNECTED | The test failed to publish to the test session because the client was not connected to the session. |
PUBLISH_TO_SESSION_PERMISSION_OR_TIMEOUT_ERROR | The test failed to publish to the test session due a permissions error or timeout. |
PUBLISH_TO_SESSION_NETWORK_ERROR | The test failed to publish to the test session due a network error. |
SUBSCRIBE_TO_SESSION_ERROR | The test encountered an unknown error while attempting to subscribe to a test stream. |
LOGGING_SERVER_CONNECTION_ERROR | The test failed to connect to the OpenTok logging server. |
testQuality() errors
If the promised returned by the testQuality()
is rejected, the error passed into the .catch()
method has a name
property set to one of the following:
Error.name property set to this property of ErrorNames ... | Description |
---|
INVALID_ON_UPDATE_CALLBACK | The updateCallback parameter is invalid. It must be a function that accepts a single parameter. |
UNSUPPORTED_BROWSER | The test is running on an unsupported browser (see Supported browsers). |
CONNECT_TO_SESSION_ERROR | The test failed to connect to the test OpenTok session due to a network error. |
CONNECT_TO_SESSION_TOKEN_ERROR | The test failed to connect to the test OpenTok session due to an invalid token. |
CONNECT_TO_SESSION_ID_ERROR | The test failed to connect to the test OpenTok session due to an invalid session ID. |
CONNECT_TO_SESSION_NETWORK_ERROR | The test failed to connect to the test OpenTok session due to a network error. |
FAILED_TO_OBTAIN_MEDIA_DEVICES | The test failed to obtain media devices (a camera or microphone). |
NO_AUDIO_CAPTURE_DEVICES | The browser cannot access a microphone. |
NO_VIDEO_CAPTURE_DEVICES | The browser cannot access a camera. |
PUBLISH_TO_SESSION_ERROR | The test encountered an unknown error while attempting to publish to a session. |
INIT_PUBLISHER_ERROR | The test failed to initialize a publisher. |
PUBLISH_TO_SESSION_NOT_CONNECTED | The test failed to publish to the test session because the client was not connected to the session. |
PUBLISH_TO_SESSION_PERMISSION_OR_TIMEOUT_ERROR | The test failed to publish to the test session due a permissions error or timeout. |
SUBSCRIBE_TO_SESSION_ERROR | The test encountered an unknown error while attempting to subscribe to a test stream. |
SUBSCRIBER_GET_STATS_ERROR | The test failed to get audio and video statistics for the test stream. |
MOS estimates
The testQuality()
results include MOS estimates for video (if supported) and audio (if supported).
A MOS estimate is a rating of audio or video quality. In subjective scoring, a user is asked
to rate quality from 1 (bad) to 5 (excellent). This module uses an objective test, calculating
the MOS value based on bitrate, packet loss ratio, and (for video) resolution. For example,
the audio MOS calculation is based on the ITU G.107 specification. These algorithms
limit the range of scores from 1.0 to 4.5.
MOS value | Meaning |
---|
3.8 - 4.5 | Excellent |
3.1 - 3.79 | Good |
2.4 - 3.09 | Fair |
1.7 - 2.39 | Poor |
1.0 - 1.69 | Bad |
Note: The audio MOS estimate is less accurate when using OpenTok.js version 2.17.5 or lower
or on Chrome version 57 or lower, because the OpenTok Network Test cannot access the round-trip time
for audio, which is factored into the MOS calculation.
Building the module
To build the module:
$ npm install
$ npm run build
Sample app
See the /sample subdirectory (and the /sample/README.md file) for a sample app.