GetReadStreamResult.cs :  » 2.6.4-mono-.net-core » System.Data » System » Data » Services » Client » C# / CSharp Open Source

//Copyright 2010 Microsoft Corporation
//
//Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. 
//You may obtain a copy of the License at 
//
//http://www.apache.org/licenses/LICENSE-2.0 
//
//Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an 
//"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
//See the License for the specific language governing permissions and limitations under the License.


namespace System.Data.Services.Client{
    using System.Diagnostics;
#if !ASTORIA_LIGHT
    using System.Net;
#else    
    using System.Data.Services.Http;
#endif

    internal class GetReadStreamResult : BaseAsyncResult
    {
        private readonly HttpWebRequest request;

        private HttpWebResponse response;

        internal GetReadStreamResult(
            object source, 
            string method, 
            HttpWebRequest request, 
            AsyncCallback callback, 
            object state)
            : base(source, method, callback, state)
        {
            Debug.Assert(request != null, "Null request can't be wrapped to a result.");
            this.request = request;
            this.Abortable = request;
        }

        internal void Begin()
        {
            try
            {
                IAsyncResult asyncResult;
                asyncResult = BaseAsyncResult.InvokeAsync(this.request.BeginGetResponse, GetReadStreamResult.AsyncEndGetResponse, this);

                this.CompletedSynchronously &= asyncResult.CompletedSynchronously;
            }
            catch (Exception e)
            {
                this.HandleFailure(e);
                throw;
            }
            finally
            {
                this.HandleCompleted();
            }

            Debug.Assert(!this.CompletedSynchronously || this.IsCompleted, "if CompletedSynchronously then MUST IsCompleted");
        }

        internal DataServiceStreamResponse End()
        {
            if (this.response != null)
            {
                DataServiceStreamResponse streamResponse = new DataServiceStreamResponse(this.response);
                return streamResponse;
            }
            else 
            {
                return null;
            }
        }

#if !ASTORIA_LIGHT
        internal DataServiceStreamResponse Execute()
        {
            try
            {
                System.Net.HttpWebResponse webresponse = null;
                try
                {
                    webresponse = (System.Net.HttpWebResponse)this.request.GetResponse();
                }
                catch (System.Net.WebException ex)
                {
                    webresponse = (System.Net.HttpWebResponse)ex.Response;
                    if (null == webresponse)
                    {
                        throw;
                    }
                }

                this.SetHttpWebResponse(webresponse);
            }
            catch (Exception e)
            {
                this.HandleFailure(e);
                throw;
            }
            finally
            {
                this.SetCompleted();
                this.CompletedRequest();
            }

            if (null != this.Failure)
            {
                throw this.Failure;
            }

            return this.End();
        }
#endif

        protected override void CompletedRequest()
        {
            Debug.Assert(null != this.response || null != this.Failure, "should have response or exception");
            if (null != this.response)
            {
                InvalidOperationException failure = null;
                if (!WebUtil.SuccessStatusCode(this.response.StatusCode))
                {
                    failure = DataServiceContext.GetResponseText(this.response.GetResponseStream, this.response.StatusCode);
                }

                if (failure != null)
                {
                    this.response.Close();
                    this.HandleFailure(failure);
                }
            }
        }

        private static void AsyncEndGetResponse(IAsyncResult asyncResult)
        {
            GetReadStreamResult state = asyncResult.AsyncState as GetReadStreamResult;
            Debug.Assert(state != null, "Async callback got called for different request.");

            try
            {
                state.CompletedSynchronously &= asyncResult.CompletedSynchronously;                HttpWebRequest request = Util.NullCheck(state.request, InternalError.InvalidEndGetResponseRequest);

                HttpWebResponse webresponse = null;
                try
                {
                    webresponse = (HttpWebResponse)request.EndGetResponse(asyncResult);
                }
                catch (WebException e)
                {
                    webresponse = (HttpWebResponse)e.Response;
                    if (null == webresponse)
                    {
                        throw;
                    }
                }

                state.SetHttpWebResponse(webresponse);
                state.SetCompleted();
            }
            catch (Exception e)
            {
                if (state.HandleFailure(e))
                {
                    throw;
                }
            }
            finally
            {
                state.HandleCompleted();
            }
        }

        private void SetHttpWebResponse(HttpWebResponse webResponse)
        {
            Debug.Assert(webResponse != null, "Can't set a null response.");
            this.response = webResponse;
        }
    }
}