Inconsistent behavior from Invoke-RestMethod from Windows Powershell to Powershell Core

[limartin]

Steps to reproduce

This same code, works in Powershell in Windows, where in Linux doesn't.

$contentType = "octet-stream"
$headers = @{"foo"="bar"}
Invoke-RestMethod -method post "http://foo/bar" -Headers $headers -ContentType $contentType -infile $chunkFile

Expected behavior

Actual behavior

The format of value 'octet-stream' is invalid. However, it does allows: "application/octect-stream"

Environment data

> $PSVersionTable
$PSVersionTable

Name                           Value
----                           -----
PSVersion                      6.0.0
PSEdition                      Core
GitCommitId                    v6.0.0
OS                             Linux 3.10.0-514.21.1.el7.x86_64 #1 SMP Thu May 25 17:04:51 UTC 2017
Platform                       Unix
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

[SteveL-MSFT]

As far as I can tell, a mimetype consists of a type/subtype. Seems like we have 3 options here:

• keep current behavior and just pass through which may be confusing to users transitioning from Windows PS to PS Core
• error/warning if type is not specified
• if no type specified, automatically prefix with "application/" (not sure how safe/dangerous it would be to do this)

cc @markekraus

[markekraus]

Strict header validation is now default in PS core. This applies to any RFC defined header supplied to -Headers or -ContentType. One can bypass strict header validation with the -SkipHeaderValidation parameter.

https://github.com/PowerShell/PowerShell/blob/master/docs/BREAKINGCHANGES.md#changes-to-web-cmdlets

More info https://get-powershellblog.blogspot.com/2017/11/powershell-core-web-cmdlets-in-depth.html#L08

[markekraus]

Actually... there seems to be some odd behavior here. -SkipHeaderValidation doesn't seem to work when -InFile is used. This is a bug. I'll have to look into it.

[markekraus]

After investigating, -SkipHeaderValidation is not being applied at all to -ContentType. I should have a PR to fix this tomorrow or later today. I have the fix code, just need to write tests.