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Connection reset issue in .net core api call (net::ERR_CONNECTION_RESET 200 (OK))

I have a .net core API service which is called from a angular client project.
When a user request a status of his payment, we will make call to this service api and this service will then call a payment gateway service to fetch the status of payment and the output result will return to the user.
When i try to integrate this i am facing this below error.
net::ERR_CONNECTION_RESET 200 (OK)
core.js:5967 ERROR Unknown Error
This above issue is not showing when i try to hit the service after putting one breakpoint. Its also returning the result.
This is how entire flow works
Client side call performs by user
this.dataservice.postFeed(method, JSON.stringify(this.initsearch)).subscribe(result => {
var response = result.body["data"];
console.log(response);
});
Server side code looks like
[HttpPost]
public async Task<IActionResult> Post([FromBody] ObjectModel searchValue)
{
ApiResponse<string> response = new ApiResponse<string>();
IBaseResult<string> result = await _adlerBo.GetPaymentStatus(searchValue);
response.Success = result.success;
response.Data = result.Data;
return Ok(response);
}
In BusinessObject.cs
public async Task<IBaseResult<string>> GetPaymentStatus(PaymentSearchModel requestModel){
string apiResponse = await PaymentStatusCheckUsingAPI(requestModel.orderid);
return apiResponse ;
}
private async Task<string> PaymentStatusCheckUsingAPI(string orderNumber)
{
string message = await PostPaymentRequestToGateway(statusApiUrl, authQueryUrlParam);
NameValueCollection param = await GetResponseMap(message);
string status = "";
string encResJson = "";
if (param != null && param.Count == 2)
{
for (int i = 0; i < param.Count; i++)
{
if ("status".Equals(param.Keys[i]))
{
status = param[i];
}
if ("enc_response".Equals(param.Keys[i]))
{
encResJson = param[i];
}
}
if (!"".Equals(status) && status.Equals("0"))
{
resJson = crypto.Decrypt(encResJson, workingKey);
}
else if (!"".Equals(status) && status.Equals("1"))
{
Console.WriteLine("failure response: " + encResJson);
}
}
return resJson;
}
private async Task<string> PostPaymentRequestToGateway(string queryUrl, string urlParam)
{
string message = "";
try
{
StreamWriter myWriter = null;// it will open a http connection with provided url
WebRequest objRequest = WebRequest.Create(queryUrl);//send data using objxmlhttp object
objRequest.Method = "POST";
//objRequest.ContentLength = TranRequest.Length;
objRequest.ContentType = "application/x-www-form-urlencoded";//to set content type
myWriter = new System.IO.StreamWriter(objRequest.GetRequestStream());
myWriter.Write(urlParam);//send data
myWriter.Close();//closed the myWriter object
// Getting Response
System.Net.HttpWebResponse objResponse = (System.Net.HttpWebResponse)objRequest.GetResponse();//receive the responce from objxmlhttp object
using (System.IO.StreamReader sr = new System.IO.StreamReader(objResponse.GetResponseStream()))
{
message = await sr.ReadToEndAsync();
//Response.Write(message);
}
}
catch (Exception exception)
{
Console.Write("Exception occured while connection." + exception);
}
return message;
}
private async Task<NameValueCollection> GetResponseMap(string message)
{
//await Task.Delay(2000); I did this with no Luck
NameValueCollection Params = new NameValueCollection();
if (message != null || !"".Equals(message))
{
string[] segments = message.Split('&');
foreach (string seg in segments)
{
string[] parts = seg.Split('=');
if (parts.Length > 0)
{
string Key = parts[0].Trim();
string Value = parts[1].Trim();
Params.Add(Key, Value);
}
}
}
return await Task.FromResult(Params);
}
Any idea how to fix this? Why its working when i put breakpoint and not otherwise.
Am i doing correct asynchronous implimentsion in my api?

Handling Parallel POST to API

I have a API Post method that takes is a string which represents a Bae64 string of bytes from a word document that the API converts to PDF. My test client sends multiple documents, each on its own task, to the API to be converted. The problem is with concurrency and writing the files. I end up with a file in use since the calls are parallel. I have tried a lot of different way to block the conversion process until a document is converted but none of it has worked. Everything works fine if it's jsut a single file being converted but as soon as it's 2 or more, the problem happens. Can anyone guide me in the correct direction to solve this issue?
API:
[HttpPost]
public async Task<SimpleResponse> Post([FromBody]string request)
{
var response = new SimpleResponse();
Task t = Task.Factory.StartNew(async () =>
{
try
{
Converter convert = new Converter();
var result = await convert.CovertDocToPDF(request, WebConfigurationManager.AppSettings["tempDocPath"], WebConfigurationManager.AppSettings["tempPdfPath"]);
response.Result = result;
response.Success = true;
}
catch (Exception ex)
{
response.Exception = ex;
response.Success = false;
response.Errors = new List<string>();
response.Errors.Add(string.Format("{0}, {1}", ex.Message, ex.InnerException?.Message ?? ""));
}
});
t.Wait();
return response;
}
Conversion code
public Task<string> CovertDocToPDF(string blob, string tempDocPath, string tempPdfPath)
{
try
{
// Convert blob back to bytes
byte[] bte = Convert.FromBase64String(blob);
// Process and return blob
return Process(bte, tempDocPath, tempPdfPath);
}
catch (Exception Ex)
{
throw Ex;
}
}
private async Task<string> Process(byte[] bytes, string tempDocPath, string tempPdfPath)
{
try
{
string rs = RandomString(16, true);
tempDocPath = tempDocPath + rs + ".docx";
tempPdfPath = tempPdfPath + rs + ".pdf";
// This is where the problem happens with concurrent calls. I added
// the try catch when the file is in use to generate a new
// filename but the error still happens.
try
{
// Create a temp file
File.WriteAllBytes(tempDocPath, bytes);
}
catch (Exception Ex)
{
rs = RandomString(16, true);
tempDocPath = tempDocPath + rs + ".docx";
tempPdfPath = tempPdfPath + rs + ".pdf";
File.WriteAllBytes(tempDocPath, bytes);
}
word.Application app = new word.Application();
word.Document doc = app.Documents.Open(tempDocPath);
doc.SaveAs2(tempPdfPath, word.WdSaveFormat.wdFormatPDF);
doc.Close();
app.Quit(); // Clean up the word instance.
// Need the bytes to return the blob
byte[] pdfFileBytes = File.ReadAllBytes(tempPdfPath);
// Delete temp files
File.Delete(tempDocPath);
File.Delete(tempPdfPath);
// return blob
return Convert.ToBase64String(pdfFileBytes);
}
catch (Exception Ex)
{
throw Ex;
}
}
Client:
public async void btnConvert_Click(object sender, EventArgs e)
{
var response = await StartConvert();
foreach (SimpleResponse sr in response)
{
if (sr.Success)
{
byte[] bte = Convert.FromBase64String(sr.Result.ToString());
string rs = RandomString(16, true);
string pdfFileName = tempPdfPath + rs + ".pdf";
if (File.Exists(pdfFileName))
{
File.Delete(pdfFileName);
}
System.IO.File.WriteAllBytes(pdfFileName, bte);
}
else
{
}
}
}
private async Task<IEnumerable<SimpleResponse>> StartConvert()
{
var tasks = new List<Task<SimpleResponse>>();
foreach (string s in docPaths)
{
byte[] bte = File.ReadAllBytes(s);
tasks.Add(ConvertDocuments(Convert.ToBase64String(bte)));
}
return (await Task.WhenAll(tasks));
}
private async Task<SimpleResponse> ConvertDocuments(string requests)
{
using (var client = new HttpClient(new HttpClientHandler() { UseDefaultCredentials = true }))
{
client.BaseAddress = new Uri(BaseApiUrl);
client.DefaultRequestHeaders.Add("Accept", "application/json");
// Add an Accept header for JSON format.
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));//application/json
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, BaseApiUrl + ApiUrl);
var data = JsonConvert.SerializeObject(requests);
request.Content = new StringContent(data, Encoding.UTF8, "application/json");
HttpResponseMessage response1 = await client.PostAsync(BaseApiUrl + ApiUrl, request.Content).ConfigureAwait(false);
var response = JsonConvert.DeserializeObject<SimpleResponse>(await response1.Content.ReadAsStringAsync());
return response;
}
}
Random String Generator
public string RandomString(int size, bool lowerCase = false)
{
var builder = new StringBuilder(size);
// Unicode/ASCII Letters are divided into two blocks
// (Letters 65–90 / 97–122):
// The first group containing the uppercase letters and
// the second group containing the lowercase.
// char is a single Unicode character
char offset = lowerCase ? 'a' : 'A';
const int lettersOffset = 26; // A...Z or a..z: length = 26
for (var i = 0; i < size; i++)
{
var #char = (char)_random.Next(offset, offset + lettersOffset);
builder.Append(#char);
}
return lowerCase ? builder.ToString().ToLower() : builder.ToString();
}

First, get rid of Task.Factory.StartNew ... t.Wait() - you don't need an additional task, the root level method is async and your blocking Wait just spoils the benefits of async by blocking synchronously.
Second, like a comment suggested above, the file name random string generator is most likely to be not really random. Either do not supply anything to the seed value of your pseudo-random gen, or use something like Environment.TickCount which should be sufficient for this. Guid.NewGuid() will work too.
Another good option for temp files is Path.GetTempFileName (also generates an empty file for you): https://learn.microsoft.com/en-us/dotnet/api/system.io.path.gettempfilename?view=netstandard-2.0
[HttpPost]
public async Task<SimpleResponse> Post([FromBody]string request)
{
var response = new SimpleResponse();
try
{
...
var result = await convert.CovertDocToPDF(...);
...
}
catch (Exception ex)
{
...
}
return response;
}

Based on your code it seems that you have a "faulty" random string generator for file name (I would say _random.Next is a suspect, possibly some locking and/or "app wide" instance could fix the issue). You can use Guid.NewGuid to create random part of file name (which in theory can have collisions also but in most practical cases should be fine) or Path.GetTempFileName:
var rs = Guid.NewGuid().ToString("N");
tempDocPath = tempDocPath + rs + ".docx";
tempPdfPath = tempPdfPath + rs + ".pdf";

Creating a load tester for an upload API with UploadFileAsync

What I am trying to accomplish here is to see how much this API can handle as far as requests per second. I am trying to consume the API in a console app that will ultimately be throwaway code. My idea was to make a for loop that would try to upload an xml document every 2 seconds. I've never done this sort of thing before so forgive my ignorance. Here's my Main method:
static void Main()
{
RunAsync().Wait();
}
And the RunAsync method:
static async Task RunAsync()
{
Uri apiUrl = new Uri("http://apiurl.com/upload/files/uploadfiles");
const string file = #"C:\simple.xml";
WebClient client = new WebClient();
for (int i = 0; i <= 100; i++)
{
client.UploadFileCompleted += FileUploadSuccess;
client.UploadFileAsync(apiUrl, file);
await Task.Delay(2000);
Console.WriteLine("Upload waiting 2 seconds...");
}
Console.WriteLine("Loop completed.");
}
And the success method:
private static void FileUploadSuccess(object sender, UploadFileCompletedEventArgs e)
{
string reply = System.Text.Encoding.UTF8.GetString(e.Result);
Console.WriteLine("The file result was: {0}", reply);
}
It throws an exception on the first time through on e.Result. Here's the exception:
An unhandled exception of type 'System.Reflection.TargetInvocationException' occurred in System.dll
After doing some research, apparently I can't call the API method (which returns an async Task) without await'ing it. Unfortunately it seems UploadFileAsync is not "awaitable."
Here's the API method:
public async Task<HttpResponseMessage> UploadFiles()
{
var pilotTokenObject = TokenHelper.CreatePilotTokenObject(Request);
byte[] fileBuffer = null;
HttpResponseMessage retVal = null;
if (pilotTokenObject != null)
{
var content = Request.Content;
if (content == null)
{
throw new PilotApiException("Empty request content", HttpStatusCode.NoContent);
}
if (!content.IsMimeMultipartContent())
{
throw new PilotApiException("Request does not contain not multi-part content");
}
var uploadModelController = new PilotUploadModelController();
//*SAVE STREAMED FILE*
string serverSavePath = ConfigurationManager.AppSettings["PilotUploadApiTempStoragePath"];
if (!Directory.Exists(serverSavePath))
Directory.CreateDirectory(serverSavePath);
var provider = new MultipartFormDataStreamProvider(serverSavePath);
await Request.Content.ReadAsMultipartAsync(provider);
var fileData = provider.FileData;
if (fileData == null || fileData.Count == 0)
{
throw new PilotApiException("No multipart/form file data present.");
}
bool uploaded = false;
//Loop through each file
fileData.ForEach((fileRequest) =>
{
if (RetryUntilFileReadable(Path.Combine(serverSavePath, fileRequest.LocalFileName), 1000, 5))
{
var fileHeader = fileRequest.Headers;
if (fileHeader != null && fileHeader.ContentDisposition != null)
{
var fileName = fileHeader.ContentDisposition.FileName.Replace("\"", "");
var fileBytes = File.ReadAllBytes(Path.Combine(serverSavePath, fileRequest.LocalFileName));
//Save File to DB
var upload = uploadModelController.UploadHelper
.AddUploadFileToDb(pilotTokenObject.CentralUserDbUserId, pilotTokenObject.ClientIp, pilotTokenObject.UserAgentString,
UploadEnums.UploadKind.PilotUploadApi, fileName, fileBytes.Length, fileBytes,
UploadEnums.EncryptionType.None);
if (upload != null)
uploaded = true;
}
}
});
if (uploaded)
{
retVal = Request.CreateResponse(HttpStatusCode.Accepted, new
{
Response = String.Format("file uploaded successfully.")
});
}
}
return retVal;
}
Am I going about this the completely wrong way? Is what I want to do even doable?

It seems to me that the following would work better in your scenario:
byte[] response = await Task.Run(() => client.UploadFile(apiUrl, file));
string reply = System.Text.Encoding.UTF8.GetString(response);
Console.WriteLine("The file result was: {0}", reply);
Console.WriteLine("Upload waiting 2 seconds...");
await Task.Delay(2000);
Trying to mix-and-match the older asynchronous API with the newer async/await doesn't seem fruitful in this case. Better to just wrap the synchronous version of the API with async/await-compatible code.
(Note that it seems to me you could just as well call Thread.Sleep(2000) instead of creating a new delay task to wait on, but the above should work fine too).

EntityTooSmall in CompleteMultipartUploadResponse

using .NET SDK v.1.5.21.0
I'm trying to upload a large file (63Mb) and I'm following the example at:
http://docs.aws.amazon.com/AmazonS3/latest/dev/LLuploadFileDotNet.html
But using a helper instead the hole code and using jQuery File Upload
https://github.com/blueimp/jQuery-File-Upload/blob/master/basic-plus.html
what I have is:
string bucket = "mybucket";
long totalSize = long.Parse(context.Request.Headers["X-File-Size"]),
maxChunkSize = long.Parse(context.Request.Headers["X-File-MaxChunkSize"]),
uploadedBytes = long.Parse(context.Request.Headers["X-File-UloadedBytes"]),
partNumber = uploadedBytes / maxChunkSize + 1,
fileSize = partNumber * inputStream.Length;
bool lastPart = inputStream.Length < maxChunkSize;
// http://docs.aws.amazon.com/AmazonS3/latest/dev/LLuploadFileDotNet.html
if (partNumber == 1) // initialize upload
{
iView.Utilities.Amazon_S3.S3MultipartUpload.InitializePartToCloud(fileName, bucket);
}
try
{
// upload part
iView.Utilities.Amazon_S3.S3MultipartUpload.UploadPartToCloud(fs, fileName, bucket, (int)partNumber, uploadedBytes, maxChunkSize);
if (lastPart)
// wrap it up and go home
iView.Utilities.Amazon_S3.S3MultipartUpload.CompletePartToCloud(fileName, bucket);
}
catch (System.Exception ex)
{
// Huston, we have a problem!
//Console.WriteLine("Exception occurred: {0}", exception.Message);
iView.Utilities.Amazon_S3.S3MultipartUpload.AbortPartToCloud(fileName, bucket);
}
and
public static class S3MultipartUpload
{
private static string accessKey = System.Configuration.ConfigurationManager.AppSettings["AWSAccessKey"];
private static string secretAccessKey = System.Configuration.ConfigurationManager.AppSettings["AWSSecretKey"];
private static AmazonS3 client = Amazon.AWSClientFactory.CreateAmazonS3Client(accessKey, secretAccessKey);
public static InitiateMultipartUploadResponse initResponse;
public static List<UploadPartResponse> uploadResponses;
public static void InitializePartToCloud(string destinationFilename, string destinationBucket)
{
// 1. Initialize.
uploadResponses = new List<UploadPartResponse>();
InitiateMultipartUploadRequest initRequest =
new InitiateMultipartUploadRequest()
.WithBucketName(destinationBucket)
.WithKey(destinationFilename.TrimStart('/'));
initResponse = client.InitiateMultipartUpload(initRequest);
}
public static void UploadPartToCloud(Stream fileStream, string destinationFilename, string destinationBucket, int partNumber, long uploadedBytes, long maxChunkedBytes)
{
// 2. Upload Parts.
UploadPartRequest request = new UploadPartRequest()
.WithBucketName(destinationBucket)
.WithKey(destinationFilename.TrimStart('/'))
.WithUploadId(initResponse.UploadId)
.WithPartNumber(partNumber)
.WithPartSize(maxChunkedBytes)
.WithFilePosition(uploadedBytes)
.WithInputStream(fileStream) as UploadPartRequest;
uploadResponses.Add(client.UploadPart(request));
}
public static void CompletePartToCloud(string destinationFilename, string destinationBucket)
{
// Step 3: complete.
CompleteMultipartUploadRequest compRequest =
new CompleteMultipartUploadRequest()
.WithBucketName(destinationBucket)
.WithKey(destinationFilename.TrimStart('/'))
.WithUploadId(initResponse.UploadId)
.WithPartETags(uploadResponses);
CompleteMultipartUploadResponse completeUploadResponse =
client.CompleteMultipartUpload(compRequest);
}
public static void AbortPartToCloud(string destinationFilename, string destinationBucket)
{
// abort.
client.AbortMultipartUpload(new AbortMultipartUploadRequest()
.WithBucketName(destinationBucket)
.WithKey(destinationFilename.TrimStart('/'))
.WithUploadId(initResponse.UploadId));
}
}
my maxChunckedSize is 6Mb (6 * (1024*1024)) as I have read that the minimum is 5Mb...
why am I getting "Your proposed upload is smaller than the minimum allowed size" exception? What am I doing wrong?
The error is:
<Error>
<Code>EntityTooSmall</Code>
<Message>Your proposed upload is smaller than the minimum allowed size</Message>
<ETag>d41d8cd98f00b204e9800998ecf8427e</ETag>
<MinSizeAllowed>5242880</MinSizeAllowed>
<ProposedSize>0</ProposedSize>
<RequestId>C70E7A23C87CE5FC</RequestId>
<HostId>pmhuMXdRBSaCDxsQTHzucV5eUNcDORvKY0L4ZLMRBz7Ch1DeMh7BtQ6mmfBCLPM2</HostId>
<PartNumber>1</PartNumber>
</Error>
How can I get ProposedSize if I'm passing the stream and stream length?

Here is a working solution for the latest Amazon SDK (as today: v.1.5.37.0)
Amazon S3 Multipart Upload works like:
Initialize the request using client.InitiateMultipartUpload(initRequest)
Send chunks of the file (loop until the end) using client.UploadPart(request)
Complete the request using client.CompleteMultipartUpload(compRequest)
If anything goes wrong, remember to dispose the client and request, as well fire the abort command using client.AbortMultipartUpload(abortMultipartUploadRequest)
I keep the client in Session as we need this for each chunk upload as well, keep an hold of the ETags that are now used to complete the process.
You can see an example and simple way of doing this in Amazon Docs itself, I ended up having a class to do everything, plus, I have integrated with the lovely jQuery File Upload plugin (Handler code below as well).
The S3MultipartUpload is as follow
public class S3MultipartUpload : IDisposable
{
string accessKey = System.Configuration.ConfigurationManager.AppSettings.Get("AWSAccessKey");
string secretAccessKey = System.Configuration.ConfigurationManager.AppSettings.Get("AWSSecretKey");
AmazonS3 client;
public string OriginalFilename { get; set; }
public string DestinationFilename { get; set; }
public string DestinationBucket { get; set; }
public InitiateMultipartUploadResponse initResponse;
public List<PartETag> uploadPartETags;
public string UploadId { get; private set; }
public S3MultipartUpload(string destinationFilename, string destinationBucket)
{
if (client == null)
{
System.Net.WebRequest.DefaultWebProxy = null; // disable proxy to make upload quicker
client = Amazon.AWSClientFactory.CreateAmazonS3Client(accessKey, secretAccessKey, new AmazonS3Config()
{
RegionEndpoint = Amazon.RegionEndpoint.EUWest1,
CommunicationProtocol = Protocol.HTTP
});
this.OriginalFilename = destinationFilename.TrimStart('/');
this.DestinationFilename = string.Format("{0:yyyy}{0:MM}{0:dd}{0:HH}{0:mm}{0:ss}{0:fffff}_{1}", DateTime.UtcNow, this.OriginalFilename);
this.DestinationBucket = destinationBucket;
this.InitializePartToCloud();
}
}
private void InitializePartToCloud()
{
// 1. Initialize.
uploadPartETags = new List<PartETag>();
InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest();
initRequest.BucketName = this.DestinationBucket;
initRequest.Key = this.DestinationFilename;
// make it public
initRequest.AddHeader("x-amz-acl", "public-read");
initResponse = client.InitiateMultipartUpload(initRequest);
}
public void UploadPartToCloud(Stream fileStream, long uploadedBytes, long maxChunkedBytes)
{
int partNumber = uploadPartETags.Count() + 1; // current part
// 2. Upload Parts.
UploadPartRequest request = new UploadPartRequest();
request.BucketName = this.DestinationBucket;
request.Key = this.DestinationFilename;
request.UploadId = initResponse.UploadId;
request.PartNumber = partNumber;
request.PartSize = fileStream.Length;
//request.FilePosition = uploadedBytes // remove this line?
request.InputStream = fileStream; // as UploadPartRequest;
var up = client.UploadPart(request);
uploadPartETags.Add(new PartETag() { ETag = up.ETag, PartNumber = partNumber });
}
public string CompletePartToCloud()
{
// Step 3: complete.
CompleteMultipartUploadRequest compRequest = new CompleteMultipartUploadRequest();
compRequest.BucketName = this.DestinationBucket;
compRequest.Key = this.DestinationFilename;
compRequest.UploadId = initResponse.UploadId;
compRequest.PartETags = uploadPartETags;
string r = "Something went badly wrong";
using (CompleteMultipartUploadResponse completeUploadResponse = client.CompleteMultipartUpload(compRequest))
r = completeUploadResponse.ResponseXml;
return r;
}
public void AbortPartToCloud()
{
// abort.
client.AbortMultipartUpload(new AbortMultipartUploadRequest()
{
BucketName = this.DestinationBucket,
Key = this.DestinationFilename,
UploadId = initResponse.UploadId
});
}
public void Dispose()
{
if (client != null) client.Dispose();
if (initResponse != null) initResponse.Dispose();
}
}
I use DestinationFilename as the destination file so I can avoid the same name, but I keep the OriginalFilename as I needed later.
Using jQuery File Upload Plugin, all works inside a Generic Handler, and the process is something like this:
// Upload partial file
private void UploadPartialFile(string fileName, HttpContext context, List<FilesStatus> statuses)
{
if (context.Request.Files.Count != 1)
throw new HttpRequestValidationException("Attempt to upload chunked file containing more than one fragment per request");
var inputStream = context.Request.Files[0].InputStream;
string contentRange = context.Request.Headers["Content-Range"]; // "bytes 0-6291455/14130271"
int fileSize = int.Parse(contentRange.Split('/')[1]);,
maxChunkSize = int.Parse(context.Request.Headers["X-Max-Chunk-Size"]),
uploadedBytes = int.Parse(contentRange.Replace("bytes ", "").Split('-')[0]);
iView.Utilities.AWS.S3MultipartUpload s3Upload = null;
try
{
// ######################################################################################
// 1. Initialize Amazon S3 Client
if (uploadedBytes == 0)
{
HttpContext.Current.Session["s3-upload"] = new iView.Utilities.AWS.S3MultipartUpload(fileName, awsBucket);
s3Upload = (iView.Utilities.AWS.S3MultipartUpload)HttpContext.Current.Session["s3-upload"];
string msg = System.String.Format("Upload started: {0} ({1:N0}Mb)", s3Upload.DestinationFilename, (fileSize / 1024));
this.Log(msg);
}
// cast current session object
if (s3Upload == null)
s3Upload = (iView.Utilities.AWS.S3MultipartUpload)HttpContext.Current.Session["s3-upload"];
// ######################################################################################
// 2. Send Chunks
s3Upload.UploadPartToCloud(inputStream, uploadedBytes, maxChunkSize);
// ######################################################################################
// 3. Complete Upload
if (uploadedBytes + maxChunkSize > fileSize)
{
string completeRequest = s3Upload.CompletePartToCloud();
this.Log(completeRequest); // log S3 response
s3Upload.Dispose(); // dispose all objects
HttpContext.Current.Session["s3-upload"] = null; // we don't need this anymore
}
}
catch (System.Exception ex)
{
if (ex.InnerException != null)
while (ex.InnerException != null)
ex = ex.InnerException;
this.Log(string.Format("{0}\n\n{1}", ex.Message, ex.StackTrace)); // log error
s3Upload.AbortPartToCloud(); // abort current upload
s3Upload.Dispose(); // dispose all objects
statuses.Add(new FilesStatus(ex.Message));
return;
}
statuses.Add(new FilesStatus(s3Upload.DestinationFilename, fileSize, ""));
}
Keep in mind that to have a Session object inside a Generic Handler, you need to implement IRequiresSessionState so your handler will look like:
public class UploadHandlerSimple : IHttpHandler, IRequiresSessionState
Inside fileupload.js (under _initXHRData) I have added an extra header called X-Max-Chunk-Size so I can pass this to Amazon and calculate if it's the last part of the uploaded file.
Fell free to comment and make smart edits for everyone to use.

I guess you didn't set the content-length of the part inside the UploadPartToCloud() function.

WCF Streaming File Transfer ON .NET 4

I need a good example on WCF Streaming File Transfer.
I have found several and tried them but the posts are old and I am wokding on .net 4 and IIS 7 so there are some problems.
Can you gives me a good and up-to-date example on that.

The following answers detail using a few techniques for a posting binary data to a restful service.
Post binary data to a RESTful application
What is a good way to transfer binary data to a HTTP REST API service?
Bad idea to transfer large payload using web services?
The following code is a sample of how you could write a RESTful WCF service and is by no means complete but does give you an indication on where you could start.
Sample Service, note that this is NOT production ready code.
[ServiceContract]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall)]
public class FileService
{
private IncomingWebRequestContext m_Request;
private OutgoingWebResponseContext m_Response;
[WebGet(UriTemplate = "{appName}/{id}?action={action}")]
public Stream GetFile(string appName, string id, string action)
{
var repository = new FileRepository();
var response = WebOperationContext.Current.OutgoingResponse;
var result = repository.GetById(int.Parse(id));
if (action != null && action.Equals("download", StringComparison.InvariantCultureIgnoreCase))
{
response.Headers.Add("Content-Disposition", string.Format("attachment; filename={0}", result.Name));
}
response.Headers.Add(HttpResponseHeader.ContentType, result.ContentType);
response.Headers.Add("X-Filename", result.Name);
return result.Content;
}
[WebInvoke(UriTemplate = "{appName}", Method = "POST")]
public void Save(string appName, Stream fileContent)
{
try
{
if (WebOperationContext.Current == null) throw new InvalidOperationException("WebOperationContext is null.");
m_Request = WebOperationContext.Current.IncomingRequest;
m_Response = WebOperationContext.Current.OutgoingResponse;
var file = CreateFileResource(fileContent, appName);
if (!FileIsValid(file)) throw new WebFaultException(HttpStatusCode.BadRequest);
SaveFile(file);
SetStatusAsCreated(file);
}
catch (Exception ex)
{
if (ex.GetType() == typeof(WebFaultException)) throw;
if (ex.GetType().IsGenericType && ex.GetType().GetGenericTypeDefinition() == typeof(WebFaultException<>)) throw;
throw new WebFaultException<string>("An unexpected error occurred.", HttpStatusCode.InternalServerError);
}
}
private FileResource CreateFileResource(Stream fileContent, string appName)
{
var result = new FileResource();
fileContent.CopyTo(result.Content);
result.ApplicationName = appName;
result.Name = m_Request.Headers["X-Filename"];
result.Location = #"C:\SomeFolder\" + result.Name;
result.ContentType = m_Request.Headers[HttpRequestHeader.ContentType] ?? this.GetContentType(result.Name);
result.DateUploaded = DateTime.Now;
return result;
}
private string GetContentType(string filename)
{
// this should be replaced with some form of logic to determine the correct file content type (I.E., use registry, extension, xml file, etc.,)
return "application/octet-stream";
}
private bool FileIsValid(FileResource file)
{
var validator = new FileResourceValidator();
var clientHash = m_Request.Headers[HttpRequestHeader.ContentMd5];
return validator.IsValid(file, clientHash);
}
private void SaveFile(FileResource file)
{
// This will persist the meta data about the file to a database (I.E., size, filename, file location, etc)
new FileRepository().AddFile(file);
}
private void SetStatusAsCreated(FileResource file)
{
var location = new Uri(m_Request.UriTemplateMatch.RequestUri.AbsoluteUri + "/" + file.Id);
m_Response.SetStatusAsCreated(location);
}
}
Sample Client, note that this is NOT production ready code.
// *********************************
// Sample Client
// *********************************
private void UploadButton_Click(object sender, EventArgs e)
{
var uri = "http://dev-fileservice/SampleApplication"
var fullFilename = #"C:\somefile.txt";
var fileContent = File.ReadAllBytes(fullFilename);
using (var webClient = new WebClient())
{
try
{
webClient.Proxy = null;
webClient.Headers.Add(HttpRequestHeader.ContentMd5, this.CalculateFileHash());
webClient.Headers.Add("X-DaysToKeep", DurationNumericUpDown.Value.ToString());
webClient.Headers.Add("X-Filename", Path.GetFileName(fullFilename));
webClient.UploadData(uri, "POST", fileContent);
var fileUri = webClient.ResponseHeaders[HttpResponseHeader.Location];
Console.WriteLine("File can be downloaded at" + fileUri);
}
catch (Exception ex)
{
var exception = ex.Message;
}
}
}
private string CalculateFileHash()
{
var hash = MD5.Create().ComputeHash(File.ReadAllBytes(#"C:\somefile.txt"));
var sb = new StringBuilder();
for (int i = 0; i < hash.Length; i++)
{
sb.Append(hash[i].ToString("x2"));
}
return sb.ToString();
}
private void DownloadFile()
{
var uri = "http://dev-fileservice/SampleApplication/1" // this is the URL returned by the Restful file service
using (var webClient = new WebClient())
{
try
{
webClient.Proxy = null;
var fileContent = webClient.DownloadData(uri);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
}