PSSlack

This is a quick and dirty module to interact with the Slack API.

Pull requests and other contributions would be welcome!

Instructions

# One time setup
    # Download the repository
    # Unblock the zip
    # Extract the PSSlack folder to a module path (e.g. $env:USERPROFILE\Documents\WindowsPowerShell\Modules\)
# Or, with PowerShell 5 or later or PowerShellGet:
    Install-Module PSSlack

# Import the module.
    Import-Module PSSlack    #Alternatively, Import-Module \\Path\To\PSSlack

# Get commands in the module
    Get-Command -Module PSSlack

# Get help
    Get-Help Send-SlackMessage -Full
    Get-Help about_PSSlack

Prerequisites

• PowerShell 3 or later
• A valid token or incoming webhook uri from Slack.
  • Grab a test token
  • Register a Slack app, grab a token - we'll try wrapping this in the module later
  • Add an incoming webhook to your team, grab the Uri

Examples

Send a Simple Slack Message

# This example shows a crudely crafted message without any attachments,
# using parameters from Send-SlackMessage to construct the message.

#Previously set up Uri from https://<YOUR TEAM>.slack.com/apps/A0F7XDUAZ
$Uri = "Some incoming webhook uri from Slack"

Send-SlackMessage -Uri $Uri `
                  -Channel '@wframe' `
                  -Parse full `
                  -Text 'Hello @wframe, join me in #devnull!'

# Send a message to @wframe (not a channel), parsing the text to linkify usernames and channels

Search for a Slack Message

# Search for a message containing PowerShell, sorting results by timestamp

Find-SlackMessage -Token $Token `
                  -Query 'PowerShell' `
                  -SortBy timestamp

# Search for a message containing PowerShell
# Results are sorted by best match by default
# Notice the extra properties and previous/next messages

Find-SlackMessage -Token $Token `
                  -Query 'PowerShell' |
    Select-Object -Property *

You could use this simply to search Slack from the CLI, or in an automated solution that might avoid posting if certain content is already found in Slack.

Send a Richer Slack Message

# This is a simple example illustrating some common options
# when constructing a message attachment
# giving you a richer message

$Token = 'A token. maybe from https://api.slack.com/docs/oauth-test-tokens'

New-SlackMessageAttachment -Color $([System.Drawing.Color]::red) `
                           -Title 'The System Is Down' `
                           -TitleLink https://www.youtube.com/watch?v=TmpRs7xN06Q `
                           -Text 'Please Do The Needful' `
                           -Pretext 'Everything is broken' `
                           -AuthorName 'SCOM Bot' `
                           -AuthorIcon 'http://ramblingcookiemonster.github.io/images/tools/wrench.png' `
                           -Fallback 'Your client is bad' |
    New-SlackMessage -Channel '@wframe' `
                     -IconEmoji 💣 |
    Send-SlackMessage -Token $Token

Notice that the title is clickable. You might link to...

• The alert in question
• A logging solution query
• A dashboard
• Some other contextual link
• Strongbad

Send Multiple Slack Attachments

# This example demonstrates that you can chain new attachments
# together to form a multi-attachment message

$Token = 'A token. maybe from https://api.slack.com/docs/oauth-test-tokens'

New-SlackMessageAttachment -Color $_PSSlackColorMap.red `
                           -Title 'The System Is Down' `
                           -TitleLink https://www.youtube.com/watch?v=TmpRs7xN06Q `
                           -Text 'Everybody panic!' `
                           -Pretext 'Everything is broken' `
                           -Fallback 'Your client is bad' |
    New-SlackMessageAttachment -Color $([System.Drawing.Color]::Orange) `
                               -Title 'The Other System Is Down' `
                               -TitleLink https://www.youtube.com/watch?v=TmpRs7xN06Q `
                               -Text 'Please Do The Needful' `
                               -Fallback 'Your client is bad' |
    New-SlackMessage -Channel '@wframe' `
                     -IconEmoji 💣 `
                     -AsUser `
                     -Username 'SCOM Bot' |
    Send-SlackMessage -Token $Token

Notice that we can chain multiple New-SlackMessageAttachments together.

Send a Table of Key Value Pairs

# This example illustrates a pattern where you might
# want to send output from a script; you might
# include errors, successful items, or other output

# Pretend we're in a script, and caught an exception of some sort
$Fail = [pscustomobject]@{
    samaccountname = 'bob'
    operation = 'Remove privileges'
    status = "An error message"
    timestamp = (Get-Date).ToString()
}

# Create an array from the properties in our fail object
$Fields = @()
foreach($Prop in $Fail.psobject.Properties.Name)
{
    $Fields += @{
        title = $Prop
        value = $Fail.$Prop
        short = $true
    }
}

$Token = 'A token. maybe from https://api.slack.com/docs/oauth-test-tokens'

# Construct and send the message!
New-SlackMessageAttachment -Color $([System.Drawing.Color]::Orange) `
                           -Title 'Failed to process account' `
                           -Fields $Fields `
                           -Fallback 'Your client is bad' |
    New-SlackMessage -Channel 'devnull' |
    Send-SlackMessage -Uri $uri

# We build up a pretend error object, and send each property to a 'Fields' array
# Creates an attachment with the fields from our error
# Creates a message fromthat attachment and sents it with a uri

Store and Retrieve Configs

To save time and typing, you can save a token or uri to a config file (protected via DPAPI) and a module variable.

This is used as the default for commands, and is reloaded if you open a new PowerShell session.

# Save a Uri and Token.
# If both are specified, token takes precedence.
Set-PSSlackConfig -Uri 'SomeSlackUri' -Token 'SomeSlackToken'

# Read the current cofig
Get-PSSlackConfig

Notes

Currently evaluating .NET Core / Cross-platform functionality. The following will not work initially:

• Serialization of URIs and tokens via Set-PSSlackConfig. Set these values per-session if needed
• [System.Drawing.Color]::SomeColor shortcut. Use the provided $_PSSlackColorMap hash to simplify this. E.g. $_PSSlackColorMap.red

There are a good number of Slack functions out there, including jgigler's PowerShell.Slack and Steven Murawski's Slack. We borrowed some ideas and code from these - thank you!

If you want to go beyond interacting with the Slack API, you might consider using a bot