51Degrees Device Detection .NET  4.2

Device detection services for 51Degrees Pipeline


Automatic updates example for 51Degrees device detection ‘Hash’ engine shows how to build a pipeline using the 51Degrees device detection pipeline builder and demonstrates how to configure the update polling interval. The automatic data file updates page explains the different options you can configure.

This example is available in full on GitHub.

This example requires a subscription to 51Degrees Device Data, a subscription can be acquired from the 51Degrees pricing page.

This example requires a local data file. Free data files can be acquired by pulling the submodules under this repository or from the device-detection-data GitHub repository.

Required NuGet Dependencies:

Expected output:

Using data file at '51Degrees-LiteV4.1.hash'
Data file published date: 13/04/2020 00:00:00
The pipeline has now been set up to poll for updates every ...
Update started for ...
Data file published date: 13/04/2020 00:00:00
Update completed. Status AUTO_UPDATE_SUCCESS
Data file published date: 02/07/2020 00:00:00
/* *********************************************************************
* 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.
* This Original Work is licensed under the European Union Public Licence (EUPL)
* v.1.2 and is subject to its terms as set out below.
* If a copy of the EUPL was not distributed with this file, You can obtain
* one at https://opensource.org/licenses/EUPL-1.2.
* The 'Compatible Licences' set out in the Appendix to the EUPL (as may be
* 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.
* 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
* in the end user terms of the application under an appropriate heading,
* such notice(s) shall fulfill the requirements of that article.
* ********************************************************************* */
using FiftyOne.Pipeline.Core.FlowElements;
using FiftyOne.Pipeline.Engines.Services;
using Microsoft.Extensions.Logging;
using System;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Threading;
public class Program
public class Example : ExampleBase
private IPipeline pipeline;
private int updatePollingInterval = 30;
private int pollingIntervalRandomisation = 10;
private EventWaitHandle ewh;
private string dataFile = "51Degrees.hash";
public void Run(string originalDataFile, string licenseKey)
// Copy the original data file to another location as we do not
// want to preserve the original for other examples.
File.Copy(originalDataFile, dataFile, true);
// Create an event wait handler to wait for the update complete
//event so that the example runs during the update process.
ewh = new EventWaitHandle(false, EventResetMode.AutoReset);
FileInfo f = new FileInfo(dataFile);
Console.WriteLine($"Using data file at '{f.FullName}'");
// Construct our own data update service so we can monitor update events.
var loggerFactory = new LoggerFactory();
var httpClient = new HttpClient();
var dataUpdateService = new DataUpdateService(loggerFactory.CreateLogger<DataUpdateService>(), httpClient);
// Bind a method to the CheckForUpdateComplete event and
// the CheckForUpdateStarted event which
// prints the published date of the data file.
dataUpdateService.CheckForUpdateComplete += LogPublishedDate;
dataUpdateService.CheckForUpdateStarted += LogPublishedDate;
// Build a new Pipeline to use an on-premise Hash engine and
// configure automatic updates.
pipeline = new DeviceDetectionPipelineBuilder(loggerFactory, httpClient, dataUpdateService)
// Use the On-Premise engine (aka Hash engine) and pass in
// the path to the data file, your license key and whether
// to use a temporary file.
// A license key is required otherwise automatic updates will
// remain disabled.
.UseOnPremise(dataFile, licenseKey, true)
// Enable automatic updates.
// Watch the data file on disk and refresh the engine
// as soon as that file is updated.
// Disable update on startup
// Set the frequency in seconds that the pipeline should
// check for updates to data files. A recommended
// polling interval in a production environment is
// around 30 minutes or 1800 seconds.
// Set the max ammount of time in seconds that should be
// added to the polling interval. This is useful in datacenter
// applications where mulitple instances may be polling for
// updates at the same time. A recommended ammount in production
// environments is 600 seconds.
// Get the published date of the data file from the Hash engine
// after building the pipeline.
var publishedDate = pipeline
Console.WriteLine($"Initial data file published date: {publishedDate}");
Console.WriteLine($"The pipeline has now been set up to poll for updates every {updatePollingInterval} seconds, " +
$"a random ammount of time up to {pollingIntervalRandomisation} seconds will be added.");
// Wait for the update complete event.
private void LogPublishedDate<T>(object sender, T e) where T : DataUpdateEventArgs
var publishedDate = pipeline
if (e is DataUpdateCompleteArgs completeArgs)
Console.WriteLine($"Update completed. Status {completeArgs.Status}");
// Set the event wait handler once the update is completed.
Console.WriteLine($"Update started for {e.DataFile.DataFilePath}");
Console.WriteLine($"Data file published date: {publishedDate}");
static void Main(string[] args)
var licenseKey = "!!Your license key!!";
if (licenseKey.StartsWith("!!"))
Console.WriteLine("You need a license key to run this example, " +
"you can obtain one by subscribing to a 51Degrees bundle: https://51degrees.com/pricing");
var defaultDataFile = "..\\..\\..\\..\\..\\..\\..\\..\\..\\device-detection-cxx\\device-detection-data\\51Degrees-LiteV4.1.hash";
var defaultDataFile = "..\\..\\..\\..\\..\\..\\..\\..\\device-detection-cxx\\device-detection-data\\51Degrees-LiteV4.1.hash";
var dataFile = args.Length > 0 ? args[0] : defaultDataFile;
new Example().Run(dataFile, licenseKey);
#if (DEBUG)
Console.WriteLine("Complete. Press key to exit.");