Json sent by xamarin has no data at end - c#

I am trying to send the following JSON file to the web API I created. But, the API is working fine and sending no data and not taking the data from the sent JSON file. While it is being able to take data from postman sent JSON file.
I have tried using the ToString() method with the JSON object and also tried postman to verify if my API is working fine. The API seems to work properly with postman send JSON file but the file sent by the Xamarin forms is sending no data in the JSON file or something and database get no data in it.
There are no errors being shown but the data is not being uploaded to the database please do help me to get this done faster.
coding is below,
public async void check2(object sender, EventArgs e)
{
var httpClient = new HttpClient();
var post = new poster {user=username.Text, pass=password.Text};
string json = JsonConvert.SerializeObject(post);
var content = new StringContent(json,Encoding.UTF8, "application/json");
content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
var response = httpClient.PostAsync("http://licapi.witlyf.com/api/values", content);
App.Current.MainPage = new NavigationPage(new navigator(username.Text));
}

The answer has been met it seems I have put my JSON file variable names to be different than in web API so when I made the same the link worked the data was submitted to the database.

Related

API GET Request Returns HTML/Text instead of JSON

This is my first time working with a RESTful API and Xamarin and etc. I have so far made a simple REST API. I have written a GET call to it that, if I write http://localhost:[num]/api/Name, it will return a JSON file of the matching Emu's information. I have tested this with Postman, so I know that it works.
I have now written an app that will call this API in order to catch this information and then display it. So far, I've got it connected to the server hosting my API, but I'm unable to get it to return JSON. Instead it seems to be returning text/HTTP.
From what I've searched up on previous Stack Overflow threads, it seems that I was missing Headers requesting that reply be in a JSON format. When I added in code that was on the official .NET documentation on Microsoft's website, it gave me issues with my Json Deserialiser. I have also added in the information in the header to make sure that it returns json.
Here is the code for the function:
async private void Submit_OnClicked(object sender, EventArgs e)
{
var nameValue = EmuName.Text;
var baseAddr = new Uri("http://my_url/HelloEmu/");
var client = new HttpClient { BaseAddress = baseAddr };
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
string url = (string)nameValue;
var returnedJson = await client.GetStringAsync(url);
Models.EmuItemModel MyEmu = JsonConvert.DeserializeObject<Models.EmuItemModel>(returnedJson);
ReturnedName.Text = MyEmu.Name;
ReturnedAge.Text = MyEmu.Age.ToString();
ReturnedWeight.Text = MyEmu.Weight.ToString();
My code actually faults on the line ReturnedWeight.Text = MyEmu.Weight.ToString()
But I'm guessing the more majour issue is occuring during deserialisng the object, because it seemingly "skips" over the preceeding two lines when I run it in the debugger.
When I run it in Visual Studio 2019, the value of "returnedJson" is this:
"<html><head><meta http-equiv=\"refresh\" content=\"0;url=http://lookup.t-mobile.com/search/?q=http://my_url/HelloEmu/Keith&t=0\"/></head><body><script>window.location=\"http://lookup.t-mobile.com/search/?q=\"+escape(window.location)+\"&r=\"+escape(document.referrer)+\"&t=0\";</script></body></html>"
I think this is an HTML output. I would love any hints about what on earth I'm doing wrong!
EDIT: Since it almost seems like the HTML is returning an error message, perhaps it could do with my url??? I've published the website using the File system method. So to access the API in Postman I'll use http://localhost:[port]/api/values, calling my website in a regular ol' browser makes it go http://my_url/HelloEmu. I get a 403 "no directory" method in return...
EDIT: Here is the Postman code:
enter image description here
Usually it happens because there are missing headers or some other malformed request, Download RestSharp DLL from NuGet, and then you can use the following, in postman, go to "Code":
And choose C# you will see a code snippet (Example):

How to read Json data from Instagram RealTime API updates

I'm trying to use Instagram RealTime API to get updates whenever someone posts an image with an specific tag, I've followed all the steps, but I'm having problems to read the json data that is sent to my callback url. According to instagram's documentation :
When someone posts a new photo and it triggers an update of one of
your subscriptions, we make a POST request to the callback URL that
you defined in the subscription. The post body contains a raw text
JSON body with update objects.
I'm using C# and MVC 5, here's my code to read the "raw text JSON body", note that I'm saving the json string in a text file.
[HttpPost]
public HttpStatusCodeResult Receive()
{
string json;
using (var reader = new StreamReader(Request.InputStream))
{
json = reader.ReadToEnd();
}
File.WriteAllText(Path.Combine(Server.MapPath("~/"), "test.txt"), json);
return new HttpStatusCodeResult(200);
}
The problem is, when I receive the request, the file is create, but is always empty. There's something wrong with my code? Could it be some problem with Instagram's API? I'd appreciate some help with this.
Found it! Just set InputStream position to zero and it works!

how to conceptually make a post request to web api from c# program as if the it's coming from html form

I have been banging my head against the wall for the past 1 week now but without any success. Actually I'm writing a C# code(a web api controller action) to call another web api to make a post request with some json data payload in the request body. Syntax-wise there is nothing wrong with the code. But when I directly call the service(web api service) from web browser I get an Html form that has a multiline text box in it, rollback property (as radio button for true and false value for this property), drop down box with 2 options such as html and json (to get response in either format) and a button(for sending request to the server and making edits in the database). Now when I manually put json data inside text box and click the button on that html form edits are done successfully in the database but when programmatically(from my C# code) I send the same json data payload and make a post request edits are never done successfully rather I get an html response body through Fiddler that says status code success 200 but unable to complete operation,some parameters couldn't be recognized.
Here is my code
private static async Task<HttpResponseMessage> GeometryUpdateAsync(Feature updatedFeature, FeatureType featureType, int? objectid = null)
{
var jsonObject = new JObject();
dynamic esriId = jsonObject;
if (objectid == null)
{
objectid = updatedFeature.OBJECTID;
}
esriId.OBJECTID = objectid;
var mergedJsonString = JsonConvert.SerializeObject(new
{
geometry = JObject.Parse(updatedFeature.Geometry.ToString()),
attributes = JObject.Parse(esriId.ToString())
});
mergedJsonString = String.Format("[{0}]", mergedJsonString);
HttpResponseMessage response = null;
using (var client = new HttpClient())
{
//string arguments = "rollbackOnFailure=true&f=pjson&features=";
client.BaseAddress = new Uri("somebaseaddress");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.Timeout = TimeSpan.FromSeconds(500.00);
//response = await client.PostAsJsonAsync("someuri", arguments + mergedJsonString);
response = await client.PostAsync("someuri", mergedJsonString, new System.Net.Http.Formatting.JsonMediaTypeFormatter());
if (response.IsSuccessStatusCode)
{
var v = response.Content.ReadAsStringAsync().Result;
}
}
}
When I look at the request body (through fiddler while making a post request through Html form) request body looks like
features=%5B%7B%22geometry%22%3A%7B%22paths%22%3A%5B%5B%5B-91.3888577181506%2C39.703158271352621%5D%91.381838690201192%2C39.690323806398723%5D%2C%5B-91.383241723424632%2C39.689645139311914%5D%2C%5B-91.3849700567206%2C39.6888078408094%5D%2C%5B-91.3861256828518%2C39.688248198995353%5D%5D%5D%7D%2C%22attributes%22%3A%7B%22OBJECTID%22%3A21%7D%5D&gdbVersion=&rollbackOnFailure=true&f=pjson
and the request body for the post request made programmatically looks likes
"[{\"geometry\":{\"paths\":[[[-91.3888577181506,39.703158271352621],[-91.381838690201192,39.690323806398723],[-91.383241723424632,39.689645139311914],[-91.3849700567206,39.6888078408094],[-91.3861256828518,39.688248198995353]]]},\"attributes\":{\"OBJECTID\":21}}]"
Even I tried appending this
string arguments = "rollbackOnFailure=true&f=pjson&features=";
in my commented out code above (where I'm using PostAsJsonAsync) to make the request body look like as if it's coming from Html form. But no success, even I'm not sure whether the JSonFormatter takes this arguments string in to account or just leaves it while serializing/deserializing during the run time. And the post request body that I get after appending "arguments" string to Json string looks like this
"rollbackOnFailure=true&f=pjson&features=[{\"geometry\":{\"paths\":[[[-91.3877577181506,39.703158271352621],[-91.36047320856953,39.702616420911333],[-91.383241723424632,39.689645139311914],[-91.3849700567206,39.6888078408094],[-91.3861256828518,39.688248198995353]]]},\"attributes\":{\"OBJECTID\":21}}]"
But still no success, Now I'm totally running out of ideas as to how to call web api service from my C# code so that web api thinks it's coming from that Html form and end up successfully doing edits in the database programmatically. All suggestions and ideas will be highly appreciated.
The trick lies somewhere else, I was using HttpClient to simulate browser post request and get result in c#. But in this particular scenario HttpClient is of no use. I changed to HttpWebRequest after seeing a code at How to make a post call to a Web Api Action? from utlimate_programmer_BR and it did the trick, again HttpClient was a bad choice by me to get this particular thing done.

Deserializing a local xml file using Rest Sharp

I have no problem deserializing an xml into my class while using the following code. I was wondering if it was possible to use the same code on a local file, as our source files are saved locally for archival purposes and are occasionally reprocessed.
This works for remote xml but not for local xml:
RestRequest request = new RestRequest();
var client = new RestClient();
//doesnt work
client.BaseUrl = directory;
request.Resource = file;
//works
client.BaseUrl = baseURL;
request.Resource = url2;
IRestResponse<T> response = client.Execute<T>(request);
return response.Data;
Is there a way to use RestSharp from a local file? I was going to try to use the same function regardless of whether the xml is local or remote and just pass it the location of the xml to read.
This is in fact possible using built in JsonDeserializer class as below. I have used this method to stub API response for testing.
// Read the file
string fileContents = string.Empty;
using (System.IO.StreamReader reader = new System.IO.StreamReader(#"C:\Path_to_File.txt"))
{
fileContents = rd.ReadToEnd();
}
// Deserialize
RestResponse<T> restResponse = new RestResponse<T>();
restResponse.Content = fileContents;
RestSharp.Deserializers.JsonDeserializer deserializer = new RestSharp.Deserializers.JsonDeserializer();
T deserializedObject = deserializer.Deserialize<T>(restResponse);
This is not possible with standard functionality. For example "file://" URLs do not work with RestSharp.
I would recommend using RestSharp do get the returned data from a Uri and having another function to deserialize this data into an object.
You can use the same funcion then to deserialize from file data.
RestSharp is a library to do REST calls, not to deserialize from arbitrary sources. Even if there is a possibility to make RestSharp believe it is talking to a website instead of a file, it would be a hack.
If you need it you could still use the XmlDeserializer from RestSharp. It expects a IRestResponse object, but it only uses the Content property from it, so it should be easy to create. It still feels like a hack though and there are more than enough other XmlSerializers out there that will do a great job

"Disconnected" response from HttpClient.PostAync()

I'm trying to fix an issue with a legacy asp.net WebForms application written about 6 years ago. I'll try to explain and hope that someone can see a fix.
Our application supports what we call an "API". Really it's just a couple of pages intended to be displayed within the pages of our customers' websites. We also provice a sample application that shows how to use it.
The sample app has some form fields for the caller to provide values. When submitted, we create a string of HTML containing a elelement with the tag that
submit()'s the form on postgback.
Example:
...
form1.submit();
This method works successfully as long as the end user puts our domain in thier trusted sites. Otherwise the user gets permission denied errors. However, recently, we've had a couple customers refuse to add us to trusted sites and
want the issue fixed another way.
One approach I've tries is to use HttpClient.PostAsync() to do what the form/script above does but from the server side.
public HttpResponseMessage Post(string address, MediaTypeWithQualityHeaderValue acceptType, List<KeyValuePair<string, string>> data)
{
using (HttpClient client = new HttpClient())
{
//client.BaseAddress = new Uri(address);
client.DefaultRequestHeaders.Accept.Add(acceptType);
HttpContent content = new FormUrlEncodedContent(data);
HttpResponseMessage response = client.PostAsync(address, content).Result;
return response.EnsureSuccessStatusCode();
}
}
It's called like this:
string hash = GenerateHashValue();
List<KeyValuePair<string, string>> data = this.BuildPostData(hash);
MediaTypeWithQualityHeaderValue acceptType = new MediaTypeWithQualityHeaderValue("text/html");
HttpResponseMessage msg = Post(this.GetPostTargetUrl(), acceptType, data);
var task = msg.Content.ReadAsStringAsync();
task.Wait();
string result = task.Result;
Response.Write(result);
Response.End();
The response HTML is successfully written into the but it's essentally "disconnected" - nothing works after that. Normally, using the / method about uses can navigate in the iframe to other pages on our
site.Looking at it in fiddler, I see that some of the posts and redirects that I see when using the current / method is happeing and I get 404s for many of the javascript files coming from our site.
Can anyone suggest another approach in which I would not have XSS errors but a "connected" iframe?
Thanks,
Dan

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