PowerShell push message to Slack incoming webhook.

example.ps1

Set-StrictMode -Version Latest

$payload = @{
	"channel" = "#my-channel"
	"icon_emoji" = ":bomb:"
	"text" = "This is my message. Hello there!"
	"username" = "Mr. Robot"
}

Invoke-WebRequest `
	-Body (ConvertTo-Json -Compress -InputObject $payload) `
	-Method Post `
	-Uri "https://hooks.slack.com/services/HOOK_API_SLUG" | Out-Null

getting this error

Invoke-WebRequest : The response content cannot be parsed because the Internet Explorer engine is not available, or Internet Explorer's first-launch configuration is not complete. Specify the UseBasicParsing parameter and try again. At D:\a_temp\f0550799-da8e-4f01-b1cf-9f5bdbca4354.ps1:10 char:1 + Invoke-WebRequest ` + ~~~~~~~~~~~~~~~~~~~ + CategoryInfo : NotImplemented: (:) [Invoke-WebRequest], NotSupportedException + FullyQualifiedErrorId : WebCmdletIEDomNotSupportedException,Microsoft.PowerShell.Commands.InvokeWebRequestComman d

@rifaterdemsahin the error pretty much covers the issue. You need to run the IE first-launch config.

A quick google gives heaps of results - e.g. http://wahlnetwork.com/2015/11/17/solving-the-first-launch-configuration-error-with-powershells-invoke-webrequest-cmdlet/

Run IE on target machine at least once to config.

or... just use the -UseBasicParsing switch.

As an alternative to Invoke-WebRequest, you can use the (already built-in) Invoke-RestMethod:

Invoke-RestMethod -Uri "https://hooks.slack.com/services/HOOK_API_SLUG" -Method Post -Body $payload -ContentType "application/json"

Thanks @pixelbath, nicely noted 👍