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Cannot serialize stream data asp .net core

Trying to deserialize objects from HTTP response.
Response stream returns information in json and I already checked if it is valid in online deserializer.
I got the object class from the API framework so I think all of the properties should be configured for the response.
Code:
var request = new HttpRequestMessage(HttpMethod.Get,
"api_url");
var client = _clientFactory.CreateClient();
var response = await client.SendAsync(request);
if (response.IsSuccessStatusCode)
{
using var responseStream = await response.Content.ReadAsStreamAsync();
var reponseString = await response.Content.ReadAsStringAsync();
var data = await JsonSerializer.DeserializeAsync<IEnumerable<Tournament>>(responseStream);
}
else
{
GetBranchesError = true;
}
I see that information in responseString is correct but data objects are always null.
Weird part is that it partially works because it shows how many objects are in the responseStream but all of the object properties are nulls.
Also tried to set the stream position to 0 - didn't help.
Any idea what I am doing wrong to deserialize these objects?
Desirializer used - System.Text.Json;
Project asp .net core 3.1

The problem is that the properties you are looking for in the JSON array are actually wrapped inside an object called "tournament". It's easier to notice when you format the JSON string nicely like this for example:
[
{
"tournament": {
"id": 1,
"name": "name1",
...
}
},
{
"tournament": {
"id": 2,
"name": "name2",
...
}
}
]
To deserialize this I would suggest you make a wrapper class to handle that:
public class TournamentItem
{
[JsonPropertyName("tournament")]
public Tournament Tournament { get; set; }
}
And then deserialize to that class:
var data = await JsonSerializer.DeserializeAsync<IEnumerable<TournamentItem>>(responseStream);
Now data.Tournament will contain all the properties.
There might still be a few issues in your properties like Spam for example. The JSON string has a null as value, but the property is not nullable - I didn't check all your properties. DeserializeAsync will throw an error and tell you.

JsonDeserializer check before try to convert Model

Read simple api call code bellow. Here i am getting call response in- IRestResponse response and its a json response. Then using JsonDeserializer() i am trying to convert it to a C# Model which is WallMartData model. ( i think i dont need to share model code here bcoz it doesn't matter for this question ). Now from this same response sometime i will get a json response which match with my model WallMartData and some time it will return other json response. Now my question is- before i try to convert my json response to WallMartData Model i want to check if this is a valid convertable json. If its not valid convartable for this WallMartData model then it will skip try to convert. Bcoz when its fails to convert i am getting invalid json exception on c#. Thats why i need to check before try to convert. Any solution?
string url = "http://api.example.com/v1/items?apiKey=" + Token + "&upc=" + UPC;
var client = new RestClient(url);
var request = new RestRequest(Method.GET);
IRestResponse response = client.Execute(request);
var deserializer = new JsonDeserializer();
var wmr = deserializer.Deserialize<WallMartData>(response);

You can try to create a method use try .... catch to check the JSON string is or isn't valid.
private static bool IsValidJson<T>(string strInput,out T obj)
{
obj = default(T);
try
{
obj = JsonConvert.DeserializeObject<T>(strInput);
return true;
}
catch (JsonReaderException jex)
{
return false;
}
catch (Exception ex)
{
return false;
}
}
Then you can use bool to check the DeserializeObject whether success.
WallMartData wmr;
if(IsValidJson<WallMartData>(response,out wmr)){
//... your logic with wmr
}

I think you can just use try catch block and it will be enough. But if you really need to validate your JSON, you can use JSON Schema. You can generate schema for your class using JsonSchemaGenerator

I suggest using JsonSchema by Json.Net
more info here
let's say that your WallMartData class looks like this
public class WallMartData
{
[JsonProperty("email", Required = Required.Always)]
public string Email;
[JsonProperty("first_name")]
public string firstName;
[JsonProperty("last_name")]
public string lastName;
}
Then you can easily use the schema checker
JSchemaGenerator generator = new JSchemaGenerator();
JSchema schema = generator.Generate(typeof(WallMartData));
string json = #"...";
JObject wallMartData = JObject.Parse(json);
if(wallMartData.IsValid(schema))
{
//if json matching the schema aka the class account
}
else
{
//the json is invalid
}

Consuming WEB API using HttpClient in c# console application

I have created a web API in visual studio 2015 using a MySQL database. The API is working perfect.
So I decided to make a console client application in which I can consume my web-service (web API). The client code is based on HttpClient, and in the API I have used HttpResponse. Now when I run my console application code, I get nothing. Below is my code:
Class
class meters_info_dev
{
public int id { get; set; }
public string meter_msn { get; set; }
public string meter_kwh { get; set; }
}
This class is same as in my web API model class:
Model in web API
namespace WebServiceMySQL.Models
{
using System;
using System.Collections.Generic;
public partial class meters_info_dev
{
public int id { get; set; }
public string meter_msn { get; set; }
public string meter_kwh { get; set; }
}
Console application code
static HttpClient client = new HttpClient();
static void ShowAllProducts(meters_info_dev mi)
{
Console.WriteLine($"Meter Serial Number:{mi.meter_msn}\t Meter_kwh: {mi.meter_kwh}", "\n");
}
static async Task<List<meters_info_dev>> GetAllRecordsAsync(string path)
{
List<meters_info_dev> mID = new List<meters_info_dev>();
HttpResponseMessage response = await client.GetAsync(path);
if (response.IsSuccessStatusCode)
{
mID = await response.Content.ReadAsAsync<List<meters_info_dev>>();
}
else
{
Console.WriteLine("No Record Found");
}
return mID;
}
static void Main()
{
RunAsync().Wait();
}
static async Task RunAsync()
{
client.BaseAddress = new Uri("http://localhost:2813/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var m = await GetAllRecordsAsync("api/metersinfo/");
foreach(var b in m)
{
ShowAllProducts(b);
}
}
In my API I have 3 GET methods under a single controller, so I have created different routes for them. Also the URL for them is different.
http://localhost:2813/api/metersinfo/ will return all records
While debugging the code, I found that List<meters_info_dev> mID = new List<meters_info_dev>(); is empty:
While the response is 302 Found, the URL is also correct:
Update 1
After a suggestion I have done the following:
using (var client = new HttpClient())
{
List<meters_info_dev> mID = new List<meters_info_dev>();
HttpResponseMessage response = await client.GetAsync(path);
if (response.IsSuccessStatusCode)
{
mID = await response.Content.ReadAsAsync<List<meters_info_dev>>();
}
else
{
Console.WriteLine("No Record Found");
}
return mID;
}
When I run the application, I get the exception "An invalid request URI was provided. The request URI must either be an absolute URI or BaseAddress must be set."
Update 2
I have added a new piece of code:
using (var cl = new HttpClient())
{
var res = await cl.GetAsync("http://localhost:2813/api/metersinfo");
var resp = await res.Content.ReadAsStringAsync();
}
And in the response I am getting all the records:
I don't know why it's not working with the other logic and what the problem is. I have also read the questions Httpclient consume web api via console app C# and Consuming Api in Console Application.
Any help would be highly appreciated.

The code needs quite a bit of work.
The line you highlighted will always be empty because that's where you initialise the variable. What you want is run thorugh the code until you get the result back form the call.
First, make sure your api actually works, you can call the GET method you want in the browser and you see results.
using (var client = new HttpClient())
{
var result = await client.GetAsync("bla");
return await result.Content.ReadAsStringAsync();
}
that's an example of course, so replace that with your particular data and methods.
now, when you check the results just because your response.IsSuccessStatusCode is false that doesn't mean there are no records. What it means is that the call failed completely. Success result with an empty list is not the same thing as complete failure.
If you want to see what you get back you can alter your code a little bit:
if(response.IsSuccessStatusCode)
{
var responseData = await response.Content.ReadAsStringAsync();
//more stuff
}
put a breakpoint on this line and see what you actually get back, then you worry about casting the result to your list of objects. Just make sure you get back the same thing you get when you test the call in the browser.
<------------------------------->
More details after edit.
Why don't you simplify your code a little bit.
for example just set the URL of the request in one go :
using (var client = new HttpClient())
{
var result = await client.GetAsync("http://localhost:2813/api/metersinfo");
var response = await result.Content.ReadAsStringAsync();
//set debug point here and check to see if you get the correct data in the response object
}
Your first order of the day is to see if you can hit the url and get the data.
You can worry about the base address once you get a correct response. Start simple and work your way up from there, once you have a working sample.
<----------------- new edit ---------------->
Ok, now that you are getting a response back, you can serialise the string back to the list of objects using something like Newtonsoft.Json. This is a NuGet package, you might either have it already installed, if not just add it.
Add a using statement at the top of the file.
using Newtonsoft.Json;
then your code becomes something like :
using (var client = new HttpClient())
{
var result = await client.GetAsync("bla");
var response = await result.Content.ReadAsStringAsync();
var mID = JsonConvert.DeserializeObject<List<meters_info_dev>>(response);
}
At this point you should have your list of objects and you can do whatever else you need.

ASP.NET MVC handle request error

In my .Net MVC app I need to handle server side validation. If there was something wrong with request I get this:
{
"validationMessage": message
}
with StatusCode = 200.
Otherwise of course I get response proper for the call. My issue is that I have troubles checking for validation messages and then deserializing response (I always get null there though fiddler shows me that response comes back).
public static async Task<Response<T>> Response<T>(HttpResponseMessage response)
{
var res = new Response<T>();
if (response.IsSuccessStatusCode)
{
//check for validation messages
var serverErrorInfo = await response.Content.ReadAsAsync<ServerError>();
if (serverErrorInfo.ValidationMessage != null)
{
res.ErrorInfo = new ErrorInfo(serverErrorInfo.ValidationMessage);
}
else
{
var result = await response.Content.ReadAsAsync<T>();
res.IsSuccess = true;
res.Result = result;
}
return res;
}
What am I doing wrong? Does the response get disposed after first attempt to read it as a ServerError? Since I use generics I cannot first check if there is response and than read the validationMessage.
ServerError Code:
[JsonObject]
public class ServerError
{
public string validationMessage{ get; set; }
}

Probably a deserialization issue. Have you tried ValidationMessage with a capital V in the json response? Also, is serverErrorInfo null entirely, or is just the property ValidationMessage null? Can you check what the value of response.Content is, right before deserialization to ServerError?

In the end the solution was just using some ugly code:
var serverErrorInfo = JsonConvert.DeserializeObject<ServerError>(await response.Content.ReadAsStringAsync());
I am very unsure why ReadAsAsync fails there.

Consuming json input from url ,deserialize into c# & retrieve values from web API

I have been stuck in trying figure out the syntax for a particular scenario.
Scenario: When I give a JSON string as argument in the URL, I want the url to consume an API and retrieve the details from that API, as per the given input.
My project needs deserialization into c# so, I used JSON.NET for the same.
Say: input is - Profile-id : 123456789
The output should consume details pertaining to that Pid and display.
The i/p given in url:
https://www.docscores.com/widget/api/org-profile/demo-health/npi/123456789
The expected o/p:
json string
What i have been doing is :
string url = "https://www.docscores.com/widget/api/org-profile/demo-health/npi/?profile-id=ShowProfile";
string data = GET(url);
dynamic jsonDe = JsonConvert.DeserializeObject(data);
var phyRatings = Convert.ToString(jsonDe.profile.averageRating);
Console.WriteLine(phyRatings);
public string ShowProfile(string pid)
{
}
public static string GET(string url)
{
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader reader = new StreamReader(stream);
string data = reader.ReadToEnd();
reader.Close();
stream.Close();
return data;
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
return null;
}
So, when I pass profile-id as 123456789 in the url, I want the syntax to extract other info with this Profile-id
I AM totally confused with the syntax in C#. How can I pass the argument and write inside the ShowProfile function? I searched everywhere but not able to find the correct syntax.
Can someone please tell me if this is the right way to do it?

EDIT: Sounds like you have two questions here. First is how to pass your Profile-Id in the URL, and the second is how to deserialize the JSON result into a C# object. But let me know if I'm misunderstanding.
For passing 123456789 as your profile ID, you just need to concatenate it into the URL string. So you might have
public string ShowProfile(string pid)
{
ProfileInfo info = GET(pid);
// Do what you want with the info here.
}
public static ProfileInfo GET(int profileId)
{
try
// Note this ends in "=" now.
string basePath = "/widget/api/org-profile/demo-health/npi/?profile-id=";
string path = basePath + profileId.ToString();
//...
ProfileInfo would be your custom class to match the JSON structure.
Then to deserialize the result, in your GET() method, you might instead try calling the service using HttpClient from the Microsoft.AspNet.WebApi.Client NuGet package, and then read that directly into a C# object whose structure maps to the JSON response you get (see example below). Your GET() method could then return that object, and then it'd be trivial for the ShowProfile() method to read the properties you want from that C# object.
public static ProfileInfo GET(int profileId)
{
try
{
// Note this ends in "=" now.
string basePath = "/widget/api/org-profile/demo-health/npi/?profile-id=";
string path = basePath + profileId.ToString();
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("https://www.docscores.com");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.GetAsync(path);
if (response.IsSuccessStatusCode)
{
ProfileInfo info = await response.Content.ReadAsAsync<ProfileInfo>();
return info;
}
}
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
return null;
}
More code and info at MSDN: Calling a Web API From a .NET Client in ASP.NET Web API 2 (C#)