VSAModule

1.6.0

Tests/VSAFakeHttp.ps1

                                # Shared test transport (F-67).

#

# Since v1.5.1 the module has a single HTTP stack built on System.Net.Http.HttpClient, so tests no

# longer simulate failures by mocking Invoke-RestMethod. Instead they install a fake

# HttpMessageHandler, which is the supported way to test HttpClient code: the real transport runs --

# its retry loop, status handling, Retry-After parsing, body reading and error typing are all

# genuinely exercised -- while the network is replaced by a scripted queue of responses.

#

# The injection seam is the module's own client cache ($script:VSAHttpClients), so no test-only hook

# exists in production code. Tests must clear that cache afterwards (see Reset-VSAFakeTransport

# usage) so subsequent code rebuilds a real client.

#

# NOTE: this file is deliberately NOT named *.Tests.ps1 -- it is dot-sourced by test files, not run

# as a test file itself.

if (-not ('FakeHttpMessageHandler' -as [type])) {

    $FakeHttpSource = @'

using System;

using System.Collections.Generic;

using System.Net;

using System.Net.Http;

using System.Net.Http.Headers;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

public class FakeHttpExchange

{

    public int Status;

    public string Body;

    public int RetryAfterSeconds;

    public bool Fault;

}

// Returns scripted responses in FIFO order and records what was actually sent.

public class FakeHttpMessageHandler : HttpMessageHandler

{

    public Queue<FakeHttpExchange> Script = new Queue<FakeHttpExchange>();

    public List<string> RequestUris = new List<string>();

    public List<string> RequestBodies = new List<string>();

    public List<string> ContentTypes = new List<string>();

    public List<string> AuthHeaders = new List<string>();

    public List<string> Methods = new List<string>();

    public int CallCount = 0;

    public void EnqueueResponse(int status, string body, int retryAfterSeconds)

    {

        Script.Enqueue(new FakeHttpExchange { Status = status, Body = body, RetryAfterSeconds = retryAfterSeconds, Fault = false });

    }

    // Simulates no HTTP response at all (socket reset / unreachable / blocked endpoint).

    public void EnqueueFault()

    {

        Script.Enqueue(new FakeHttpExchange { Fault = true });

    }

    protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)

    {

        CallCount++;

        Methods.Add(request.Method.Method);

        RequestUris.Add(request.RequestUri.ToString());

        AuthHeaders.Add(request.Headers.Contains("Authorization") ? string.Join(",", request.Headers.GetValues("Authorization")) : null);

        if (request.Content != null)

        {

            RequestBodies.Add(request.Content.ReadAsStringAsync().Result);

            ContentTypes.Add(request.Content.Headers.Contains("Content-Type") ? string.Join(",", request.Content.Headers.GetValues("Content-Type")) : null);

        }

        else { RequestBodies.Add(null); ContentTypes.Add(null); }

        if (Script.Count == 0)

            throw new InvalidOperationException("FakeHttpMessageHandler: no scripted exchange left for " + request.RequestUri);

        FakeHttpExchange x = Script.Dequeue();

        if (x.Fault) throw new HttpRequestException("simulated connection reset");

        var resp = new HttpResponseMessage((HttpStatusCode)x.Status);

        resp.Content = new StringContent(x.Body ?? string.Empty, Encoding.UTF8, "application/json");

        if (x.RetryAfterSeconds > 0)

            resp.Headers.RetryAfter = new RetryConditionHeaderValue(TimeSpan.FromSeconds(x.RetryAfterSeconds));

        return Task.FromResult(resp);

    }

}

'@

    # The framework reference set differs by edition; 5.1 resolves System.Net.Http from the GAC.

    $FakeHttpRefs = if ($PSVersionTable.PSEdition -eq 'Core') {

        @('System.Net.Http', 'System.Net.Primitives', 'System.Runtime', 'System.Collections', 'System.Threading.Tasks', 'netstandard')

    } else {

        @('System.Net.Http')

    }

    Add-Type -TypeDefinition $FakeHttpSource -ReferencedAssemblies $FakeHttpRefs -ErrorAction Stop

}