My web app is running fine on my local machine but when published to a Windows Azure Website, I get the following error on one of the controller action methods:
502 - Web server received an invalid response while acting as a gateway or proxy server. There is a problem with the page you are looking for, and it cannot be displayed. When the Web server (while acting as a gateway or proxy) contacted the upstream content server, it received an invalid response from the content server.
I used Elmah to capture more information and I get: System.ArgumentNullException Value cannot be null. Parameter name: path2
So it's referencing when I use path.combine(path1, path2) in my method. I can't figure out what is going on, the input file is being read fine and the output files are being generated fine when I check the output directory.
Any other suggestions on what might be going on?
Here is the code for my action method:
[HttpPost]
public ActionResult ProcessProducts(UploadViewModel model)
{
DateTime startTime = DateTime.UtcNow;
DateTime endTime;
TimeSpan totalTime;
PulProcessor prodManager = new PulProcessor();
string filePath = Path.Combine(Server.MapPath("~/files/incoming"), model.ProductsFileName);
try
{
using (TextReader prodFile = System.IO.File.OpenText(filePath))
{
CsvReader csv = new CsvReader(prodFile);
// map is at end of this file
csv.Configuration.RegisterClassMap<PulMap>();
List<PulProduct> prodList = csv.GetRecords<PulProduct>().ToList();
foreach (var product in prodList)
{
prodManager.ProcessProduct(product);
}
}
}
catch (Exception ex)
{
Elmah.ErrorSignal.FromCurrentContext().Raise(ex);
}
string currentDate = DateTime.UtcNow.ToString("yyyyMMdd");
string productFileName = "PUL" + currentDate + ".txt";
string exceptionsFileName = "PUL" + currentDate + "belowcost.txt";
WriteFile(prodManager.Products, productFileName);
WriteFile(prodManager.BelowCost, exceptionsFileName);
endTime = DateTime.UtcNow;
totalTime = endTime - startTime;
ViewBag.StartTime = startTime.ToString();
ViewBag.EndTime = endTime.ToString();
ViewBag.TotalTime = totalTime.ToString();
ViewBag.TotalOutput = prodManager.Products.Count.ToString();
ViewBag.ProductCounter = prodManager.RecordsProcessed;
ViewBag.FileName = productFileName;
ViewBag.ExFileName = exceptionsFileName;
ViewBag.Exceptions = prodManager.BelowCost.Count.ToString();
return View();
}
private void WriteFile(List<PulFinalProduct> prodList, string fileName)
{
try
{
string filePath = Path.Combine(Server.MapPath("~/files/pul"), fileName);
StreamWriter writer = new StreamWriter(filePath, false);
StringBuilder fileHeader = new StringBuilder();
fileHeader.Append("Inventory Number\t");
fileHeader.Append("MPN\t");
fileHeader.Append("Retail Price\t");
fileHeader.Append("Seller Cost\t");
fileHeader.Append("Buy It Now Price\t");
fileHeader.Append("Starting Bid\t");
fileHeader.Append("ChannelAdvisor Store Price\t");
fileHeader.Append("Quantity\t");
fileHeader.Append("Quantity Update Type\t");
fileHeader.Append("UPC\t");
fileHeader.Append("Weight\t");
fileHeader.Append("Brand\t");
fileHeader.Append("Manufacturer\t");
using (writer)
{
writer.WriteLine(fileHeader.ToString());
foreach (var product in prodList)
{
StringBuilder productLine = new StringBuilder();
productLine.Append(product.InventoryNumber + "\t");
productLine.Append(product.MPN + "\t");
productLine.Append(product.RetailPrice.ToString() + "\t");
productLine.Append(product.SellerCost.ToString() + "\t");
productLine.Append(product.BINPrice.ToString() + "\t");
productLine.Append(product.StartingBid.ToString() + "\t");
productLine.Append(product.CAStorePrice + "\t");
productLine.Append(product.Quantity + "\t");
productLine.Append(product.QUType + "\t");
productLine.Append(product.UPC + "\t");
productLine.Append(product.Weight + "\t");
productLine.Append(product.Brand + "\t");
productLine.Append(product.Manufacturer + "\t");
writer.WriteLine(productLine.ToString());
}
}
}
catch (Exception ex)
{
Elmah.ErrorSignal.FromCurrentContext().Raise(ex);
}
}
Here is what the Azure Eventlog gives me:
Value cannot be null. Parameter name: path2 at System.IO.Path.Combine(String path1, String path2) at Jemco.Web.Controllers.PartsUnlimitedController.ProcessProducts(UploadViewModel model) at lambda_method(Closure , ControllerBase , Object[] ) at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) at System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__36(IAsyncResult asyncResult, ActionInvocation innerInvokeState) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3c() at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass45.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3e() at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass30.<BeginInvokeActionMethodWithFilters>b__2f(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass1e.<>c__DisplayClass28.<BeginInvokeAction>b__19() at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass1e.<BeginInvokeAction>b__1b(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) at System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) at System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) at System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) at System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__4(IAsyncResult asyncResult, ProcessRequestState innerState) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End() at System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) at System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
OK, I was able to do remote debugging on this azure site. The code inside my controller action is running fine. After I get the original 502 error, the controller continues to process the input data and then write the output files. Everything works fine and the only problem I'm having is getting a 502 page while I am waiting for it to process and load the next view. Does a controller have a certain amount of time to return a view and if it doesn't is this why I'm getting the 502 error?
EDIT: I'm pretty sure what I'm experiencing is a timeout error because my controller method takes too long to run. I probably can't speed up the controller method so I'm not sure what I can do. I don't think I can or should change timeout settings on the server so maybe there something using ajax that can be done like sending a status update to the browser after every so often. I'm totally new to this so I'll have to do some research.
