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Json – What's the best way to get result from ReadAsStringAsync response?

What I have

This code calling my API:

HttpResponseMessage response = await Http.GetAsync("https://localhost:7094/api/MyResource/94d0e5ca-2be7-42f7-94dc-13955c11595c");
response.EnsureSuccessStatusCode();
string responseBody = await response.Content.ReadAsStringAsync();

Console.WriteLine($"RESPONSE: {responseBody}");

var payload = JsonSerializer.Deserialize<MyClass>(responseBody);
var json = JsonSerializer.Serialize(payload);

Console.WriteLine($"PAYLOAD: {json}");

This code is called from OnInitializedAsync in a NET8 Blazor WASM client.

The response I get

The first WriteLine of the responseBody returns this:

{
    "creationOptions": 0,
    "id": 226,
    "isCanceled": false,
    "isCompleted": true,
    "isCompletedSuccessfully": true,
    "isFaulted": false,
    "result": {
        "content": {
            <Actual content>
        },
        "links": {
            <my hateoas links>
        }
    },
    "status": 5
}

That is correct.

What’s failing

The deserialize of MyClass does not seem to happen correctly, because the second writeline returns this:

PAYLOAD: null

That’s not unsurprising because the responseBody has added the http get results. I need to go down the json tree once.

I can’t do:

var payload = JsonSerializer.Deserialize<MyClass>(responseBody.result);

Because responseBody is of type string, as you can see above.

I have also tried

to use

var payload = Http.GetFromJsonAsync<Payload<MyClass>>("https://localhost:7094/api/MyResource/94d0e5ca-2be7-42f7-94dc-13955c11595c");

But that returns:

{ "content": null, "links": null }

I suspect that’s a timing issue (data is not ready yet when I writeline).

What’s the best way to get my actual payload from the json responseBody?

Tags:

2

Answers


  1. 0

    You can try:

    {
HttpResponseMessage response = await Http.GetAsync("API");
response.EnsureSuccessStatusCode();
string responseBody = await response.Content.ReadAsStringAsync();
Console.WriteLine($"RESPONSE: {responseBody}");
var fullResponse = JsonSerializer.Deserialize<MyClass>(responseBody);

var payload = fullResponse?.result?.content;

if (payload != null)
{
    var json = JsonSerializer.Serialize(payload);
    Console.WriteLine($"PAYLOAD: {json}");
}
else
{`enter code here`
    Console.WriteLine("Payload is null or not found in the response structure.");
}
}
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  2. 0

    Not a full answer but:

    The first WriteLine of the responseBody returns this:

    It seems that you need to fix your https://localhost:7094/api/MyResource/94d0e5ca-2be7-42f7-94dc-13955c11595c endpoint first. It seems that for some reason you are returning/serializing Task<TResult> instead of TResult which leads to the corresponding output. There are multiple possible reasons for that, like missing await in the code, or incorrect value used for serialization (the code for endpoint is needed for more precise advice).

    returns this: PAYLOAD: null
    That’s not unsurprising because the responseBody has added the http get results.

    That is actually surprising, since the response contains a JSON object, an non-null instance of MyClass should be deserialized to a non-nullable instance, though it properties obviously would not be correctly filled.

    Also if you are not actually serializing System.Task<TResult> instance then you can always create a container and use it for deserialization. Something along these lines:

    public ResponseResult<T>
{
   [JsonPropertyName("result")]
   public T Result { get; set; }
}

    MyClass payload = JsonSerializer.Deserialize<ResponseResult<MyClass>>(responseBody).Result;
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