internal bool ValidateBusinessRules(FlowValidationRules rules, out List <string> errorMessages)
{
var acceptedFileExtensions = new AcceptedFileExtensions();
errorMessages = new List <string>();
if (rules.MaxFileSize.HasValue && TotalSize > rules.MaxFileSize.Value)
{
errorMessages.Add(rules.MaxFileSizeMessage ?? "size");
}
if (!acceptedFileExtensions.IsExtensionAllowed(rules.AcceptedExtensions, FileName))
{
errorMessages.Add(rules.AcceptedExtensionsMessage ?? "type");
}
return(errorMessages.Count == 0);
}
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
var flowJs = new FlowJsRepo();
var request = filterContext.HttpContext.Request;
var validationRules = new FlowValidationRules();
validationRules.AcceptedExtensions.AddRange(Extensions);
validationRules.MaxFileSize = Size;
var status = flowJs.PostChunk(request, Path.GetTempPath(), validationRules);
if (status.Status == PostChunkStatus.Done)
{
var parameterDescriptor = filterContext.ActionDescriptor
.Parameters
.FirstOrDefault(x => x.ParameterType == typeof(FlowFile));
filterContext.ActionArguments[parameterDescriptor.Name] = new FlowFile
{
flowFilename = status.FileName,
path = Path.Combine(Path.GetTempPath(), status.FileName)
};
return;
}
if (status.Status == PostChunkStatus.Error)
{
//TODO: Figure out how we can return the flow errors to the client
filterContext.Result = new BadRequestResult();
}
else
{
filterContext.Result = new AcceptedResult();
}
base.OnActionExecuting(filterContext);
}
private FlowJsPostChunkResponse PostChunkBase(HttpRequest request, string folder, FlowValidationRules validationRules)
{
Console.WriteLine($"Request Content-Length={request.ContentLength}");
//var body = new StreamReader(request.Body).ReadToEnd();
//Console.WriteLine($"Request Body={body}");
var chunk = new FlowChunk();
var requestIsSane = chunk.ParseForm(request.Form);
if (!requestIsSane)
{
Console.WriteLine("Experienced an error in the submitted form - form damaged?");
var errResponse = new FlowJsPostChunkResponse {
Status = PostChunkStatus.Error
};
errResponse.ErrorMessages.Add("damaged");
}
List <string> errorMessages = null;
var file = request.Form.Files[0];
var response = new FlowJsPostChunkResponse
{
FileName = chunk.FileName,
Size = chunk.TotalSize
};
var chunkIsValid = true;
Console.WriteLine("Processing validation rules");
if (validationRules != null)
{
chunkIsValid = chunk.ValidateBusinessRules(validationRules, out errorMessages);
}
if (!chunkIsValid)
{
Console.WriteLine($"Experienced an error while validating rules {errorMessages.Aggregate((s, a) => s + " " + a)}");
response.Status = PostChunkStatus.Error;
response.ErrorMessages = errorMessages;
return(response);
}
var chunkFullPathName = GetChunkFilename(chunk.Number, chunk.Identifier, folder);
try
{
// create folder if it does not exist
Console.WriteLine($"Opening or creating folder {folder}");
if (!Directory.Exists(folder))
{
Directory.CreateDirectory(folder);
}
// save file
using (var chunkFile = File.Create(chunkFullPathName))
{
Console.WriteLine($"Saving chunk file {chunkFullPathName} of length {file.Length}");
file.CopyTo(chunkFile);
}
}
catch (Exception)
{
Console.WriteLine("Error saving chunk");
throw;
}
// see if we have more chunks to upload. If so, return here
for (int i = 1, l = chunk.TotalChunks; i <= l; i++)
{
var chunkNameToTest = GetChunkFilename(i, chunk.Identifier, folder);
Console.WriteLine($"Checking if chunk exists already {chunkNameToTest}");
var exists = File.Exists(chunkNameToTest);
if (!exists)
{
Console.WriteLine("Some chunks are missing. Sending PartlyDone response");
response.Status = PostChunkStatus.PartlyDone;
return(response);
}
}
// Due to timing issues, we may have all chunks uploaded state for all chunks, causing the file to be merged up to n times, where n is the number of chunks
// To resolve this, we will have a global lock on a filename lock dict, and then lock the filename lock
// Allowing multiple files to be uploaded at once, with one global lock to set the filename state
lock (dictLock)
{
if (!fileLocks.ContainsKey(chunk.Identifier))
{
Console.WriteLine($"Created a lock for Identifier {chunk.Identifier} TID: {Thread.CurrentThread.ManagedThreadId}");
fileLocks[chunk.Identifier] = new object();
}
}
var localLock = fileLocks[chunk.Identifier];
if (Monitor.TryEnter(localLock))
{
try
{
Console.WriteLine($"Claimed a lock for Identifier {chunk.Identifier} TID: {Thread.CurrentThread.ManagedThreadId}");
// if we are here, all chunks are uploaded
var fileArray = new List <string>();
Console.WriteLine("All chunks done. the full list of chunks is:");
for (int i = 1, l = chunk.TotalChunks; i <= l; i++)
{
Console.WriteLine("flow-" + chunk.Identifier + "." + i);
fileArray.Add("flow-" + chunk.Identifier + "." + i);
}
MultipleFilesToSingleFile(folder, fileArray, chunk.FileName);
Console.WriteLine("Deleting old chunks");
for (int i = 0, l = fileArray.Count; i < l; i++)
{
try
{
Console.WriteLine($"Deleting {fileArray[i]}");
File.Delete(Path.Combine(folder, fileArray[i]));
}
catch (Exception)
{
Console.WriteLine("Error deleting chunk file");
}
}
response.Status = PostChunkStatus.Done;
return(response);
}
finally
{
// We can remove the lock here, as everyone else will have returned
Console.WriteLine($"Released lock for Identifier {chunk.Identifier}");
Monitor.Exit(localLock);
// Don't need to lock here
fileLocks.Remove(chunk.Identifier);
}
}
// The file has already been locked, so we don't need to do anything as it's currently being merged, and that request will return 200
Console.WriteLine($"All chunks completed, but a lock has already been claimed for Identifier {chunk.Identifier} TID: {Thread.CurrentThread.ManagedThreadId}");
response.Status = PostChunkStatus.PartlyDone;
return(response);
}
public FlowJsPostChunkResponse PostChunk(HttpRequest request, string folder, FlowValidationRules validationRules = null)
{
return(PostChunkBase(request, folder, validationRules));
}