Adsk.Platform.HttpClient 0.1.15

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
• Error handling
• Url Redirection
• [Concurrency rate limit](#Preventive 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;
}

Preventive rate limit

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);
}