Every once in a while when I'm running my app I get really "REALLY" strange characters in my output instead of the appropriate page. Now I know that this is because of some error, but unfortunately the error doesn't present it's self, but rather just produces strange characters.
Here's an example of a complete page source code.
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I have never seen this with web forms.
EDIT:
So I did some testing today and found some interesting stuff. First of all, the app was throwing a Null Reference Exception (500). Secondly the local debugger saw the error and threw a yellow screen of death right away. The bad text was being shown on the Staging server which currently runs a Release build.
So basically 500 errors on Release builds with customErrors off on my staging server throws CrAzY characters instead of failing gracefully to the yellow screen of death.
EDIT 2:
As per @Esteban's answer, here is my compression filter
Namespace Filters
Public Class CompressFilter : Inherits ActionFilterAttribute
''' <summary>
''' GZip compresses each Action when loaded. This satisfies YSlow and
''' PageSpeed.
''' </summary>
''' <param name="filterContext">The filter context.</param>
Public Overrides Sub OnActionExecuting(ByVal filterContext As ActionExecutingContext)
Dim request As HttpRequestBase = filterContext.HttpContext.Request
Dim acceptEncoding As String = request.Headers("Accept-Encoding")
If String.IsNullOrEmpty(acceptEncoding) Then
Return
End If
acceptEncoding = acceptEncoding.ToUpperInvariant()
Dim response As HttpResponseBase = filterContext.HttpContext.Response
If acceptEncoding.Contains("GZIP") Then
response.AppendHeader("Content-encoding", "gzip")
response.Filter = New GZipStream(response.Filter, CompressionMode.Compress)
ElseIf acceptEncoding.Contains("DEFLATE") Then
response.AppendHeader("Content-encoding", "deflate")
response.Filter = New DeflateStream(response.Filter, CompressionMode.Compress)
End If
End Sub
End Class
End Namespace
I'm setting this filter globally on every controller via a Base Controller. The page runs just fine if there are no other 500 errors, but if I have a 500 error peek it's ugly head, I get the funky characters.
Also, sometimes I don't have an error on my development server, but there is one on the Staging server. This happened recently when I didn't have the updated library on the staging server, but it was present on my Dev machine. I can see the errors in the Event Log, but I cannot see it on the web page... even if I set Custom Errors to Off.
EDIT 3:
Ok, so now we've discovered that this error comes because my <CompressionFilter()> doesn't decompress the stream if a 500 error is thrown. Gotta figure out how to decompress my output no matter what.