Hook Octopus Deployment into Slack Notifications. Example with resources to assist modifying.

OctopusDeploySlackNotification.ps1

## Resources
## Original: https://library.octopusdeploy.com/step-templates/21a2ae12-e721-42c1-901d-d6ed08007ca7/actiontemplate-slack-notify-deployment

## Slack API JSON
## https://api.slack.com/docs/messages/builder

## Octopus Variables
## http://docs.octopusdeploy.com/display/OD/System+variables


## DEBUG -- Shows in output log

##write-host $OctopusParameters['Octopus.Release.Number'];
##write-host $OctopusParameters['Octopus.Release.Notes'];

function Slack-Rich-Notification ($notification)
{
    $payload = @{
        channel = $OctopusParameters['Channel']
        username = $OctopusParameters['Username'];
        icon_url = $OctopusParameters['IconUrl'];
        attachments = @(
            @{
            fallback = $notification["fallback"];
            color = $notification["color"];
            fields = @(
                @{
                title = $notification["title"];
                value = $notification["value"];
                });
            };
        );
    }

    Invoke-RestMethod -Method POST -Body ($payload | ConvertTo-Json -Depth 4) -Uri $OctopusParameters['HookUrl']  -ContentType 'application/json'
}

$IncludeMachineName = [boolean]::Parse($OctopusParameters['IncludeMachineName']);
if ($IncludeMachineName) {
    $MachineName = $OctopusParameters['Octopus.Machine.Name'];
    $FormattedMachineName = "($MachineName)";
}

$OctopusReleaseNotes    = $OctopusParameters['Octopus.Release.Notes'];
$OctopusReleaseNumber   = $OctopusParameters['Octopus.Release.Number'];
$OctopusEnvironmentName = $OctopusParameters['Octopus.Environment.Name'];


if ($OctopusParameters['Octopus.Deployment.Error'] -eq $null){
    Slack-Rich-Notification @{
        title = "Deployed release $OctopusReleaseNumber to $OctopusEnvironmentName";
        value = "Release Notes: $OctopusReleaseNotes";
        fallback = "Deployed $OctopusProjectName release $OctopusReleaseNumber to $OctopusEnvironmentName successfully";
        color = "good";
    };
} else {
    Slack-Rich-Notification @{
        title = "Failed deploy of release $OctopusReleaseNumber to $OctopusEnvironmentName";
        value = "Deploy $OctopusProjectName release $OctopusReleaseNumber to $OctopusEnvironmentName $FormattedMachineName";
        fallback = "Failed to deploy $OctopusProjectName release $OctopusReleaseNumber to $OctopusEnvironmentName";
        color = "danger";
    };
}

With inspiration from this I also created a script that includes the url back to octopus. Handy when you want to see what went wrong with a failed deploy: https://gist.github.com/jiimaho/106efaa6193e7aeac3100d5427a591ce