I am working on a WP7 application. If an error happens, I want to log the error back to my server. To handle this, I have created a WCF service operation. I want this operation to be REST ful so that I can later use it with iPhone and Android apps. Because I'm writing information to the database, I thought the POST method would be best. For this reason, I'm using WebInvoke. To do this, I'm using the following code:
[OperationContract]
[WebInvoke(UriTemplate = "/LogError/{message}/{stackTrace}", ResponseFormat = WebMessageFormat.Json)]
public void LogError(string message, string stackTrace)
{
// Write info to the database
}
From my WP7 app, I want to call this operaiton via a WebClient. My question is, how do I do that? I don't understand how to call the LogError operation and pass along the required data via the WebClient.
Thank you for your help!
If I am getting your Service method correctly, that method is not a POST method. You can just call that with a WebClient
WebClient wc = new WebClient()
Uri uri = new Uri("http://yourUri/LogError/ABC/XYZ"); //ABC is your message and XYZ is your stacktrace string.
wc.DownloadStringAsync(uri);
Or if you are thinking about real HTTP 'POST' then below might help.
You can use HttpWebRequest to do a POST on to any service which is accepting POST
This link may be helpful - WCF REST POST XML - The remote server returned an error: (400) Bad Request
Something along the lines:
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://serveraddress/LogError/{message}/{stackTrace}");
If you would want to send additional information later on, you can do so with:
request.Method = "POST";
request.BeginGetRequestStream(new AsyncCallback(ExecuteAction), request);
And have a callback:
void ExecuteAction(IAsyncResult result)
{
HttpWebRequest request = (HttpWebRequest)result.AsyncState;
using (Stream s = request.EndGetRequestStream(result))
{
s.Write(data, 0, data.Length);
}
}
If there is a specific string response from the service, you might as well include the data in the WebClient and use DownloadStringAsync to get the response data.
For starters, I found a website that should help you get started with calling the service from WP7.
Try this and let me know what you think
Have a look at this post http://blog.ike.to/2011/02/02/wp7-application-crash-reporter/
It sounds like it will pretty much do what you need already, although you might want to tweak it to suit your own service interface.
Related
I received a Postman json collection from an API vendor that works perfectly, but has something mystifying to me: The request is in a GET format, yet there is an x-www-form-urlencoded body.
URL: https://login.microsoftonline.com/d1e<secret>9563/oauth2/token
And when I look at the postman-generated c# code, the mystery continues:
var client = new RestClient("https://login.microsoftonline.com/d1e...d3/oauth2/token");
client.Timeout = -1;
var request = new RestRequest(Method.GET);
request.AddHeader("Content-Type", "application/x-www-form-urlencoded");
request.AddParameter("grant_type", "client_credentials");
request.AddParameter("client_id", "c06bb...79");
request.AddParameter("client_secret", "7~u...D");
request.AddParameter("resource", "https://vault.azure.net");
IRestResponse response = client.Execute(request);
Console.WriteLine(response.Content);
Note the AddParameter constructions for a GET call. To me, this must be a slight-of-hand for merely adding those values to the querystring. But when I look at the postman console I see:
In the postman console I would have expected to see those params appended to the url as a querystring, and then everything would have made sense. But you can see that it's a bonafide Request Body.
When I make GET calls in my c# code I like to use the simple yet solid WebClient object to call the DownloadString() method. But this method is only for GETs and there's no way to send a form-post style body, understandably.
Is postman truly sending a GET with all those values being appended to the url as a querystring? And should I do the same in my DownloadString() call? Or is there something else going on here? Should I instead, in my c#, be calling the UploadString() method and sending a form post BODY as a GET??
Http protocol supports adding a body to a request, but the WebClient class you use doesn't. Presumably because it isn't considered the norm.
I'm sure there's good reasons for Microsoft using it in the OAuth flow though. Those guys normally do things right!
HTTP GET with request body
API is just an abstraction , you can send what ever you want to the API . It depends on the implementation , how the server handles these data.
Some services considers only what it requires and ignores other information
some services considers the entire requests and validates that it has only the allowed data. what should be allowed depends on the service
Postman is just a client that sends data to server , its upto you to decide what all information it should send . If you dont need any body then keep it as none. if you need some thing then add it.
I am currently working on a OAuth2 implementation. However I am stuck on an Error 401. It seems like there is something wrong with my post request that is supposed to retrieve the access token from the Company the User logged in to. This is my code:
internal void RequestAccessToken(string code)
{
string requestBody = "grant_type="+ WebUtility.UrlEncode(GRANTTYPE)+ "&code=" + WebUtility.UrlEncode(code)+"&redirect_uri="+ WebUtility.UrlEncode(REDIRECT_URI);
WebClient client = new WebClient();
client.Headers.Add("Authorization",HeaderBase64Encode(CLIENT_ID, SECRETKEY));
var response = client.UploadString("https://thewebsiteiamcallingto.com/some/api", requestBody);
var responseString = client.OpenRead("https://thewebsiteiamcallingto.com/some/api");
}
My Questions are:
Is there anything wrong with the way I try to make the POST request ?
Is there a way to retrieve the whole string that is posted to the URI using UploadString?
P.S. I have seen this post regarding the POST creation. However I find the async part to be too complicated for my case.
Since we dont know the api documentation, I would suggest you to make a postman request and view the actual request sent and response received, and secondly make a request using your method and capture using a utility like wireshark and compare the difference.
I have 2 WCF services:
1. Inbound - the client calls this service.
2. Outbound - we send information to client.
We now know that the response from client will be in default http response for outbound, and they want us to send a default http response for inbound.
Right now, I have specified the response object as a class. How do I implement http response?, how can I manage my services to send a http response?.
I have tried to search around but I am not getting any starter links for this.
Could you please guide me in the right direction?
What should my response object look like in this case?
I solved my issue with this:
To set the response object with the value:
WebOperationContext ctx = WebOperationContext.Current;
ctx.OutgoingResponse.StatusCode = System.Net.HttpStatusCode.OK;
To retrieve the value I used this:
int statuscode = HttpContext.Current.Response.StatusCode;
string description = HttpContext.Current.Response.StatusDescription;
The lack of documentation on this subject coupled with the fact that I'm struggling with a learning curve on all fronts and making me really confused about where to start. I need to get this done using C# if possible. I apologize for the vagueness of this question, but I'm really lost. I would love links to comprehensive guides/references.
In my efforts to get this done, I've run into the following problems/questions:
I've created a web service using the otrs gui, with the operation CreateTicket, but requests via C# to my chosen namespace are returning 404 (not found). When I try to add a service reference or web reference with that namespace, I get the same error. However, when I plug that namespace into my browser as the url, it displays "customer.pl".
Can I send a soap request without adding the web service as a service reference in visual studio? Given the previous problem I'm having I can't do it that way. Would I just build the soap request string and write it to the web request's data stream with http://domain/rpc.pl as the uri?
If the answer to the previous question is yes... When trying the below code segment I get an internal server error (500) on the last line. However the header looks like a SOAP header which confuses me because I wouldn't have thought it got that far.
var document = new StringBuilder();
document.Append("<UserLogin>some user login</UserLogin>");
document.Append("<Password>some password</Password> ");
document.Append("<Ticket>");
document.Append("<Title>some title</Title> ");
document.Append("<CustomerUser>some customer user login</CustomerUser>");
document.Append("<Queue>some queue</Queue>");
document.Append("<State>some state</State>");
document.Append("<Priority>some priority</Priority>");
document.Append("</Ticket>");
document.Append("<Article>");
document.Append("<Subject>some subject</Subject>");
document.Append("<Body>some body</Body>");
document.Append("<ContentType>text/plain; charset=utf8</ContentType>");
document.Append("</Article>");
//var uri = new Uri("http://domain/injest");
var uri = new Uri("http://domain/rpc.pl");
var httpWebReq = (HttpWebRequest)WebRequest.Create(uri);
var bytePostData = Encoding.UTF8.GetBytes(document.ToString());
httpWebReq.Timeout = 5 * 1000;
httpWebReq.Method = "POST";
httpWebReq.ContentLength = bytePostData.Length;
httpWebReq.ContentType = "text/xml;charset=utf-8";
//httpWebReq.TransferEncoding=
//httpWebReq.ContentType = "application/xml";
//httpWebReq.Accept = "application/xml";
var dataStream = httpWebReq.GetRequestStream();
dataStream.Write(bytePostData, 0, bytePostData.Length);
dataStream.Close();
var httpWebResponse = (HttpWebResponse)httpWebReq.GetResponse();
Even if all you can offer is where to start, it would help me to know how to proceed, as I'm stumped.
You're using the rpc.pl endpoint which is part of the 'old' RPC-style interface.
You mention you added the web service via the GUI which means you're using the 'new' Generic Interface, which is indeed much easier from .Net.
The address of the endpoint is /otrs/nph-genericinterface.pl/Webservice/GenericTicketConnector or whatever you have called the web service in the admin section.
I have a simple Restful service being called from a console app so am using WebClient. I am wondering if this call for Delete is correct.
The url looks like localhost/RestService1/Person/1
using (var client = new WebClient())
{
client.UploadString(url, "DELETE", "");
}
I don't like that UploadString does not have an overload without a data parameter. The passing of an empty parameter is not sitting well with me. Is there a better method to use for a DELETE?
I could use WebRequest but I want to just use WebClient to keep it consistent.
Here is the WebRequest block
var request = WebRequest.Create(url);
request.Method = "DELETE";
var response = (HttpWebResponse)request.GetResponse();
Both blocks work fine but what is best? Or is there a better way?
The following works for me:
client.UploadValues(url, "DELETE", new NameValueCollection());
The WebClient class doesn't really lend well to restful api consumption, I've used 3rd party libraries like RestSharp in the past that are geared more towards this type of web request. I'm pretty sure RestSharp just uses HttpWebRequest under the covers, but it provides a lot of semantics that make consuming and reusing rest resources easier.
Go get the Microsoft.Net.Http client libraries http://nuget.org/packages/Microsoft.Net.Http
HttpClient is a much better client to use for working with an API.
Sorry this is my solution in vb.net i sure that anyone can translate to c#
It's very important to drop headers, i had to comment header about Accept and Content-Type and work fine..... of course I did send the token
Dim rest As WebClient = New WebClient()
rest.Headers.Add(HttpRequestHeader.Authorization, "Bearer " & Token)
'rest.Headers.Add(HttpRequestHeader.Accept, "application/json")
'rest.Headers.Add(HttpRequestHeader.ContentType, "application/json")
result = System.Text.Encoding.UTF8.GetString(rest.UploadValues(host_api & uri, "DELETE", New NameValueCollection()))