CODEWITHSUNDEEP
c#.net.net-coreazure-functionsdotnet-httpclient
Genc Hani
Genc Hani

Reputation: 105

HttpClient get request cancellation, in case the operation takes longer than x minutes

I am writing an azure function which synchronizes data every 15 minutes. I am targeting .net 3.1 for azure function and I am using httpclient to send a get request to their API.

var response = await client.GetStringAsync()

It usually takes about 20 seconds to get the results, however, sometimes their server does not process the request correctly or it is just busy, and takes too long to do so or does not return any data. I've tested in postman, and I get status Ok 200, but it keeps loading for many minutes, and nothing happens. However, if you just cancel the operation, and try again, it is responds fine.

Now My question is, how could I keep track of the time it takes for the result to come from my get client.GetStringAsync() method, and somehow cancel the operation if lets say it is longer than 2 minutes?

Upvotes: 1

Views: 3392

Answers (1)

Frank Fajardo
Frank Fajardo

Reputation: 7359

If you are using .NET 5, you can use a CancellationTokenSource with a 'cancel after' and pass the token to client.GetStringAsync(), like this:

var cts = new CancellationTokenSource()
cts.CancelAfter(120000);  // Cancel after 2 minutes

try
{
    var response = await client.GetStringAsync(uri, cts.Token);
}
catch (TaskCanceledException)
{
    Console.WriteLine("\nTask cancelled due to timeout.\n");
}

Then you can wrap the operation in a try-catch block to see if the operation was cancelled by the token.

Reference: Cancel async tasks after a period of time (C#)

UPDATE

On .NET Core, you can specify a timeout for your HttpClient. Note however that this timeout applies to all requests you send using that instance of HttpClient. If you wish to do it that way, you can do as follows:

client.Timeout = TimeSpan.FromMinutes(2);

try
{
    var response = await client.GetStringAsync(uri);
}
catch (TaskCanceledException)
{
    Console.WriteLine("\nRequest cancelled due to timeout.\n");
}

Upvotes: 4

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