Adsk.Platform.HttpClient 0.1.3

Adsk.Platform.HttpClient

Adsk.Platform.HttpClient is a dependency of the APS toolkit libraries, and it's used by default to make HTTP requests to the Autodesk Platform (APS) API endpoints.

Adsk.Platform.HttpClient is a implementation of System.Net.Http.HttpClient.

Compare to the standard System.Net.Http.HttpClient, this implementation has the following features:

• Retry logic
• Response decompression
• Error handling
• Url Redirection
• Concurrency rate limit

Installation

dotnet add package Adsk.Platform.DataManagement

This package is a dependency of the other packagesAdsk.Platform.*.

Usage

In the following example, we create a new instance of DataManagementClient is based on the HttpClient implementation.

using Autodesk.DataManagement;

public async Task<Hubs> GetHub()
{

    async Task<string> getAccessToken()
    {
        //return access token with your logic
    }

    var DMclient = new DataManagementClient(getAccessToken);

    var hubs = await DMclient.DataMgtApi.Project.V1.Hubs.GetAsync();

    return hubs;
}

Concurrency rate limit

The concurrency rate limit can be enabled with the HttpClient constructor. The rate limit is defined by the maximum number of concurrent requests and the time window. This limit is per endpoint.

public async Task GetUsersConcurrently()
{

    //Limit to 10 requests per second
    var requestTimeWindow = TimeSpan.FromMilliseconds(1000);
    var httpClient = Autodesk.Common.HttpClientLibrary.HttpClient.Create((10, requestTimeWindow));

    //Just run all tasks in parallel. The HttpClient will handle the concurrency rate limit
    var tasks = new List<Task>();
    for (int i = 0; i < 20; i++)
    {
        var resp = httpClient.GetAsync("https://randomuser.me/api/");
        tasks.Add(resp);

    }

    await Task.WhenAll(tasks);

    }

By default, the concurrency rate limit is disabled.

Note: The concurrency rate limit is per endpoint, not global.

Error handling

The error handler throw an HttpRequestException exception if:

• Status code is not in the range 200-299
• Status code is not handled by the retry logic or the redirection logic

The exception message contains the response status code and the endpoint response content as a string.

using Autodesk.DataManagement;

public async Task<Hubs> GetHub()
{

    async Task<string> getAccessToken()
    {
        //return access token with your logic
    }

    var DMclient = new DataManagementClient(getAccessToken);

    try {

        var hubs = await DMclient.DataMgtApi.Project.V1.Hubs.GetAsync();
        return hubs;

    } catch (HttpRequestException ex) {

        Console.WriteLine(ex.StatusCode);
        Console.WriteLine(ex.Message); //Response content returned by the API endpoint

    }
}

Retry logic

The client uses the default retry logic provided with Kiota. The code below shows which status codes are considered as 'retry-able'.

private static bool ShouldRetry(HttpStatusCode? statusCode)
{
    return statusCode switch
    {
        HttpStatusCode.ServiceUnavailable => true,
        HttpStatusCode.GatewayTimeout => true,
        (HttpStatusCode)429 => true,
        _ => false
    };
}

Url Redirection

The client uses the default redirection logic provided with Kiota. The code below shows which status codes are considered as redirection.

private static bool IsRedirect(HttpStatusCode statusCode)
{
    return statusCode switch
    {
        HttpStatusCode.MovedPermanently => true,
        HttpStatusCode.Found => true,
        HttpStatusCode.SeeOther => true,
        HttpStatusCode.TemporaryRedirect => true,
        (HttpStatusCode)308 => true,
        _ => false
    };
}

Bring your own HttpClient

This default httpClient can be replaced by your own implementation.

For example, the Polly library could be used to implement a retry policy.

using System;
using System.Net.Http;
using Microsoft.Extensions.Http;
using Microsoft.Extensions.Http.Resilience;
using Polly;
using Autodesk.DataManagement;

public async Task<Hubs> GetHub()
{

    async Task<string> getAccessToken()
    {
        //return access token with your logic
    }

    // Create a custom HttpClient
    var customHttpClient = CreateHttpClient();

    //Pass it to the DataManagementClient
    var DMclient = new DataManagementClient(getAccessToken, customHttpClient);

    var hubs = await DMclient.DataMgtApi.Project.V1.Hubs.GetAsync();

    return hubs;
}

// Create a custom HttpClient with a Polly retry policy
private HttpClient CreateHttpClient() {

    var retryPipeline = new ResiliencePipelineBuilder<HttpResponseMessage>()
        .AddRetry(new HttpRetryStrategyOptions
        {
            BackoffType = DelayBackoffType.Exponential,
            MaxRetryAttempts = 3
        })
        .Build();
    
    var socketHandler = new SocketsHttpHandler
    {
        PooledConnectionLifetime = TimeSpan.FromMinutes(15)
    };

    var resilienceHandler = new ResilienceHandler(retryPipeline)
    {
        InnerHandler = socketHandler,
    };
    
    return new HttpClient(resilienceHandler);
}