Feature: Add top-level variables to slack template in order to support slack's workflow builder

[tran-christian]

Related to

Service (scheduled tasks, alerts)

Impact

major improvement to user experience

Missing Feature

Add webhook support for slack's builtin workflow builder. The workflow builder only has access to top-level fields of the incoming payload.

It would allow users to easily add webhooks to slack using the builtin workflow builder without having to create or use a third party app where there may also be restrictions in enterprise environments.

Implementation

Add all variables such as title, title_link, text, color, author, version to the top-level for the slack payload. We can still retain the existing variables such as attachments and fields so it does not break existing webhook implementations.

Design

Perhaps the slack.tmpl could be updated to something like this or similar.

{
    "title": "Task: {{ .Name }}",
    "title_link": "{{ .Task.URL }}",
    "text": "execution #{{ .Task.ID }}, status: {{ .Task.Result }}!",
    "color": "{{ .Color }}",
    "author" : "{{ .Author }}",
    {{ if .Task.Version }}
    "version": "{{ .Task.Version }}",
    {{ end }}
    "attachments": [
        {
            "title": "Task: {{ .Name }}",
            "title_link": "{{ .Task.URL }}",
            "text": "execution #{{ .Task.ID }}, status: {{ .Task.Result }}!",
            "color": "{{ .Color }}",
            "mrkdwn_in": [
                "text"
            ],
            "fields": [
                {
                    "title": "Author",
                    "value": "{{ .Author }}",
                    "short": true
                {{ if .Task.Version }}
                },
                {
                    "title": "Version",
                    "value": "{{ .Task.Version }}",
                    "short": true
                {{ end }}
                }
            ]
        }
    ]
}