Original Response Body Unattainable from Web Cmdltes on Non-Success Status Codes #5555
Description
When a non-success status code is returned the web cmdlets provide a convenient error message and attaches the HttpResponseMessage object to the Response property of the exception. In 5.1 cmdltes which wrap Invoke-RestMethod and Invoke-WebRequest could run the following to retrieve the raw response body:
try {
Invoke-WebRequest 'http://httpbin.org/status/418' -ErrorAction Stop
}
Catch {
$err = $_
}
$Stream = $err.Exception.Response.GetResponseStream()
$Stream.Position = 0
$Reader = [System.IO.StreamReader]::new($Stream)
$Reader.ReadToEnd()This is needed because sometimes the response body for error codes contain useful information about why something failed.
In 6.0.0 the equivalent code is below in the "Steps to Reproduce", This would work except that the web cmdltes are disposing the stream after creating the error message:
This makes it impossible to get the original stream. This would probably not be a problem except that there are encoding issues to consider and that the string in the error message is doctored to make it more human readable:
I recommend not disposing the streamreader and let it naturally fall out of scope as there does not appear to be a way to dispose of a streamreader without closing the underlying stream.
Steps to reproduce
try {
Invoke-WebRequest 'http://httpbin.org/status/418' -ErrorAction Stop
}
Catch {
$err = $_
}
$Stream = $err.Exception.Response.Content.ReadAsStreamAsync().GetAwaiter().GetResult()
$Stream.Position = 0
$Reader = [System.IO.StreamReader]::new($Stream)
$Reader.ReadToEnd()Expected behavior
-=[ teapot ]=-
_...._
.' _ _ `.
| ."` ^ `". _,
\_;`"---"`|//
| ;/
\_ _/
`"""`
Actual behavior
Exception calling ".ctor" with "1" argument(s): "Stream was not readable."
At line:1 char:1
+ $Reader = [System.IO.StreamReader]::new($Stream)
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : ArgumentException
You cannot call a method on a null-valued expression.
At line:1 char:1
+ $Reader.ReadToEnd()
+ ~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (:) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull
Environment data
Name Value
---- -----
PSVersion 6.0.0-rc
PSEdition Core
GitCommitId v6.0.0-rc
OS Microsoft Windows 10.0.15063
Platform Win32NT
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0...}
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
WSManStackVersion 3.0