Rest API C# - how is it possible to pass Stream argument

Question

I need to call the following REST API

[OperationContract]
[WebInvoke(Method = "POST",
UriTemplate = "/{subscriptionId}/servers?op=ChangeSubscription")]
Stream ChangeAllServersSubscription(string subscriptionId, Stream requestStream);

How can I create and pass Stream requestStream? The stream will contain JSON formatted string

Answer 1

Before making use of any kind of Stream, you should ask the API supplier which stream he's expecting to receive.

Here's an example using a MemoryStream, after you create your JSON:

// Random objects, just to make the code clear
var myObject = new {Name = "Yakov"};
var myId = "1";
var myJson = JsonConvert.SerializeObject(myObject);

// Create a MemoryStream (Encoding should be as needed)
var memoryStream = new MemoryStream(Encoding.UTF8.GetBytes(myJson));

// Call your code
var responseStream = ChangeAllServersSubscription(myId, memoryStream);

// And dispose the MemoryStream after you're done.
memoryStream.Dispose();

Answer 2

You can create a HttpWebRequest on the client side, set the url to point to your service, set appropriate method- in your case POST. For example:

HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create("http://server/id/servers?op=ChangeSubscription");
request.Method = "POST";

Then use GetRequestStream() to get the stream on the client side, write your json into this stream, close the stream, then execute the request by calling GetResponse().

    Stream stream= request.GetRequestStream();
    //stream.Write write contents of your file here!
    stream.Close();
    HttpWebResponse response= (HttpWebResponse)request.GetResponse();
    //process the response from server

If everything went right your web service will get hit and receive your file.