Using Moq to test HttpClient RequestClientCredentialsTokenAsync-CodePudding

I am trying to mock an Http Client that uses the IdentityModel extension to request a client credentials token.

var tokenResponse = await _httpClient.RequestClientCredentialsTokenAsync(requestContent);

I started doing the setup with:

var httpClient = new Mock<HttpClient>();


var httpResponseMessage = new HttpResponseMessage(HttpStatusCode.OK)
{
    Content = JsonContent.Create(new
    {
        access_token = "token",
        expires_in = 5000
    })
};

var tokenResponse = ProtocolResponse.FromHttpResponseAsync<TokenResponse>(httpResponseMessage);

httpClient.Setup(x => x.RequestClientCredentialsTokenAsync(It.IsAny<ClientCredentialsTokenRequest>(), It.IsAny<CancellationToken>())).Returns(tokenResponse);

But i end up with:

System.NotSupportedException : Unsupported expression: x => x.RequestClientCredentialsTokenAsync(It.IsAny(), It.IsAny()) Extension methods (here: HttpClientTokenRequestExtensions.RequestClientCredentialsTokenAsync) may not be used in setup / verification expressions.

How can i mock the RequestClientCredentialsTokenAsync extension?

CodePudding user response：

Looking at the internals of RequestClientCredentialsTokenAsync we can see that the base request it is using is SendAsync, so we need to mock SendAsync.

Extension call:

response = await client.SendAsync(request, cancellationToken).ConfigureAwait();

Final Setup:

var httpClient = new Mock<HttpClient>();

var httpResponseMessage = new HttpResponseMessage(HttpStatusCode.OK)
{
    Content = JsonContent.Create(new
    {
        access_token = "token",
        expires_in = 5000
    })
};

httpClient.Setup(x => x.SendAsync(It.IsAny<HttpRequestMessage>(), It.IsAny<CancellationToken>())).Returns(Task.FromResult(httpResponseMessage));

Result: