Azure Easy Apis InvokeApi Method is calling GET instead of POST

Question

I am currently working on creating a custom authentication for a Xamarin.Android app using Azure. I have successfully created my API and it is properly returning values when submitting a raw payload using Advanced REST Client.

I am now trying to implement this on Xamarin.Android using Azure's MobileServiceClient SDK and when using the invokeApi method as demonstrated below in my code, I am getting an exception indicating that it is calling GET instead of POST. Is anyone aware of what I might be doing wrong?

ex.Message returns

"Cannot GET /api/register?username=azureAccountTest&password=testingpassword"

    public async Task RegisterAsync()
    {
        Dictionary<string, string> user = new Dictionary<string, string>
        {
            { "username", username },
            { "password", password }
        };
        try
        {
            CancellationToken ct;
            var result = await client.InvokeApiAsync("register", HttpMethod.Post, user, ct);
        }
        catch(Exception ex)
        {
            var message = ex.Message;
        }
    }

Answer 1

According to your description, I tested this issue on my local side and I could retrieve the authenticationToken as follows:

You used the following method for InvokeApiAsync:

public Task<JToken> InvokeApiAsync(string apiName, HttpMethod method, IDictionary<string, string> parameters, CancellationToken cancellationToken = default(CancellationToken));

Note: It summarizes that the Additional data will sent to through the query string.

Per my understanding, you could refer to the following method for sending additional data though the HTTP content as follows:

JObject user = new JObject();
user.Add("username", "bruce");
user.Add("password", "123456");
var result = await App.MobileService.InvokeApiAsync("/.auth/login/custom", HttpMethod.Post, user, ct);

Additionally, you need to specific the mobileAppUri with https endpoint when deploy to azure side. Here is a similar issue, you could refer to here. Moreover, I would recommend you refer to adrian hall's book about Custom Authentication.

UPDATE:

Based on your comment, I checked the custom authentication and found the following note from adrian hall's book about Custom Authentication:

You must turn on Authentication / Authorization in your App Service. Set the Action to take when request is not authenticated to Allow Request (no action) and do not configure any of the supported authentication providers.