This example demonstrates device detection using user-agent client hints in a real-world scenario. When a clint-hints-enabled user first visits a website, the server will recieve the sec-ch-ua and sec-ch-ua-mobile headers. Along with the user-agent. This information is then used to determine if the client supports user-agent client hints and request them if needed by setting the Accept-CH header in the response. Clicking the button below will cause a new request to be sent to the server, along with any additional headers that have been requested.
This example is available in full on GitHub.
To run this example, you will need to create a resource key. The resource key is used as shorthand to store the particular set of properties you are interested in as well as any associated license keys that entitle you to increased request limits and/or paid-for properties.
You can create a resource key using the 51Degrees Configurator.
Make sure to include all the required properties used by this example.
Expected output:
User Agent Client Hints Example
Hardware Vendor: [...]
Hardware Name: [...]
Device Type: [...]
...
/* *********************************************************************
* This Original Work is copyright of 51 Degrees Mobile Experts Limited.
* Copyright 2019 51 Degrees Mobile Experts Limited, 5 Charlotte Close,
* Caversham, Reading, Berkshire, United Kingdom RG4 7BY.
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* v.1.2 and is subject to its terms as set out below.
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* amended by the European Commission) shall be deemed incompatible for
* the purposes of the Work and the provisions of the compatibility
* clause in Article 5 of the EUPL shall not apply.
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* If using the Work as, or as part of, a network application, by
* including the attribution notice(s) required under Article 5 of the EUPL
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const require51 = (requestedPackage) => {
try {
return require('/../../../' + requestedPackage);
} catch (e) {
return require(requestedPackage);
}
};
const core = require51('fiftyone.pipeline.core');
require((process.env.directory || __dirname) +
'/../../../deviceDetectionCloudPipelineBuilder');
// Helper function to read property values from flowData
const getValueHelper = (flowData, propertyKey) => {
var device = flowData.device;
try {
const property = device[propertyKey];
if (property.hasValue && property) {
return property.value;
} else {
return property.noValueMessage;
}
} catch (error) {
return 'Not found in cloud';
}
};
const myResourceKey = process.env.RESOURCE_KEY || '!!YOUR_RESOURCE_KEY!!';
// We need 'server' to be defined here so that, when this example
// is executed as part of a unit test, the server can be closed
// once the test is complete.
let server;
// Pipeline variable to be used
var pipeline;
const setPipeline = (resourceKey) => {
// Create a new Device Detection pipeline and set the config.
// You need to create a resource key at https://configure.51degrees.com
// and paste it into the code.
pipeline = new DeviceDetectionCloudPipelineBuilder({
resourceKey: resourceKey
}).build();
// Logging of errors and other messages.
// Valid logs types are info, debug, warn, error
pipeline.on('error', console.error);
};
if (myResourceKey === '!!YOUR_RESOURCE_KEY!!' &&
process.env.JEST_WORKER_ID === undefined) {
console.log('You need to create a resource key at ' +
'https://configure.51degrees.com and paste it into the code, ' +
'replacing !!YOUR_RESOURCE_KEY!!');
} else {
const http = require('http');
server = http.createServer((req, res) => {
const flowData = pipeline.createFlowData();
// Add any information from the request
// (headers, cookies and additional client side provided information)
flowData.evidence.addFromRequest(req);
flowData.process().then(function () {
res.statusCode = 200;
// Some browsers require that extra HTTP headers are explicitly
// requested. So set whatever headers are required by the browser in
// order to return the evidence needed by the pipeline.
// More info on this can be found at
// https://51degrees.com/blog/user-agent-client-hints
core.Helpers.setResponseHeaders(res, flowData);
res.setHeader('Content-Type', 'text/html');
let output = '';
// Generate the HTML
output = '<h2>User Agent Client Hints Example</h2>';
output += `
<p>
By default, the user-agent, sec-ch-ua and sec-ch-ua-mobile HTTP headers
are sent.
<br />
This means that on the first request, the server can determine the
browser from sec-ch-ua while other details must be derived from the
user-agent.
<br />
If the server determines that the browser supports client hints, then
it may request additional client hints headers by setting the
Accept-CH header in the response.
<br />
Select the <strong>Make second request</strong> button below,
to use send another request to the server. This time, any
additional client hints headers that have been requested
will be included.
</p>
<button type="button" onclick="redirect()">Make second request</button>
<script>
// This script will run when button will be clicked and device detection request will again
// be sent to the server with all additional client hints that was requested in the previous
// response by the server.
// Following sequence will be followed.
// 1. User will send the first request to the web server for detection.
// 2. Web Server will return the properties in response based on the headers sent in the request. Along
// with the properties, it will also send a new header field Accept-CH in response indicating the additional
// evidence it needs. It builds the new response header using SetHeader[Component name]Accept-CH properties
// where Component Name is the name of the component for which properties are required.
// 3. When "Make second request" button will be clicked, device detection request will again
// be sent to the server with all additional client hints that was requested in the previous
// response by the server.
// 4. Web Server will return the properties based on the new User Agent Client Hint headers
// being used as evidence.
function redirect() {
sessionStorage.reloadAfterPageLoad = true;
window.location.reload(true);
}
window.onload = function () {
if ( sessionStorage.reloadAfterPageLoad ) {
document.getElementById('description').innerHTML = "<p>The information shown below is determined using <strong>User Agent Client Hints</strong> that was sent in the request to obtain additional evidence. If no additional information appears then it may indicate an external problem such as <strong>User Agent Client Hints</strong> being disabled in your browser.</p>";
sessionStorage.reloadAfterPageLoad = false;
}
else{
document.getElementById('description').innerHTML = "<p>The following values are determined by sever-side device detection on the first request.</p>";
}
}
</script>
<div id="evidence">
<strong></br>Evidence values used: </strong>
<table>
<tr>
<th>Key</th>
<th>Value</th>
</tr>
`;
const evidences = pipeline.getElement('cloud').evidenceKeyFilter.filterEvidence(flowData.evidence.getAll());
for (const key in evidences) {
if (key.includes('header.user-agent') ||
key.includes('header.sec-ch')) {
output += '<tr>';
output += '<td>' + key + '</td>';
output += '<td>' + evidences[key] + '</td>';
output += '</>';
}
}
output += '</table>';
output += '</div>';
output += '<div id=description></div>';
output += '<div id="content">';
output += '<p>';
output += '<strong>Detection results:</strong></br></br>';
output += '<b>Hardware Vendor:</b> ' + getValueHelper(flowData, 'hardwarevendor');
output += '<br />';
output += '<b>Hardware Name:</b> ' + getValueHelper(flowData, 'hardwarename');
output += '<br />';
output += '<b>Device Type:</b> ' + getValueHelper(flowData, 'devicetype');
output += '<br />';
output += '<b>Platform Vendor:</b> ' + getValueHelper(flowData, 'platformvendor');
output += '<br />';
output += '<b>Platform Name:</b> ' + getValueHelper(flowData, 'platformname');
output += '<br />';
output += '<b>Platform Version:</b> ' + getValueHelper(flowData, 'platformversion');
output += '<br />';
output += '<b>Browser Vendor:</b> ' + getValueHelper(flowData, 'browservendor');
output += '<br />';
output += '<b>Browser Name:</b> ' + getValueHelper(flowData, 'browsername');
output += '<br />';
output += '<b>Browser Version:</b> ' + getValueHelper(flowData, 'browserversion');
output += '<br /></div>';
res.end(output);
});
});
// Don't run the server if under TEST
if (process.env.JEST_WORKER_ID === undefined) {
setPipeline(myResourceKey);
const port = 3000;
server.listen(port);
console.log('Server listening on port: ' + port);
};
}
module.exports = {
server: server,
setPipeline: setPipeline
};