The Slack action

contentrules.slack registers one content rule action, Post a message to Slack, named plone.actions.Slack.

The action is available for every triggering event, and for every type of content.

Fields

Field	Required	Default	Interpolated	Sent to Slack as
Webhook url	Yes	None	No	The URL of the request
Channel	Yes	None	No	channel
Pretext	No	None	Yes	attachments[0].pretext
Title	Yes	None	Yes	attachments[0].title
Title Link	No	${absolute_url}	Yes	attachments[0].title_link
Text	Yes	None	Yes	text and attachments[0].fallback
Color	No	None	No	attachments[0].color
Icon	No	None	No	icon_emoji
Username	Yes	Plone CMS	No	username
Fields	No	None	Values only	attachments[0].fields

Interpolated fields accept string interpolation variables, such as ${title} or ${user_fullname}. The variables are resolved against the object that triggered the rule. The Classic UI form of the action lists every available variable.

Leading and trailing whitespace is removed from every interpolated value. A field left empty is sent as an empty string.

Webhook url

Must be a URL, typically https://hooks.slack.com/services/….

Color

One of good, warning, danger, or a hexadecimal color code such as #439FE0.

Icon

An emoji code, such as :flag-br:.

Important

Slack ignores Channel, Icon, and Username for incoming webhooks created by a Slack app. Those webhooks always post to the channel, and with the name and icon, chosen when the app was installed. Only legacy incoming webhooks honor these three fields.

Fields syntax

Fields adds a small table to the bottom of the message. Define one table entry per line, in the format title|value|short.

Title|${title}|True
Review State|${review_state_title}|False

title

The label of the entry. It is not interpolated.

value

The content of the entry. It is interpolated.

short

True displays the entry side by side with other short entries. The value is case-insensitive. Any value other than true counts as False.

A line that does not have exactly three parts, separated by |, is ignored.

Message payload

The action sends a JSON payload to the webhook, such as the following example.

{
  "attachments": [
    {
      "color": "good",
      "fallback": "Welcome to our friend Sebastião Salgado",
      "title": "Sebastião Salgado just logged in at Site",
      "title_link": "https://www.example.com/",
      "pretext": "User logged in",
      "fields": [
        {
          "title": "User email",
          "value": "salgado@not-really-a-mail.com",
          "short": false
        }
      ]
    }
  ],
  "icon_emoji": ":flag-br:",
  "text": "Welcome to our friend Sebastião Salgado",
  "username": "Plone CMS",
  "channel": "#plone-users"
}

The following image shows where each field appears in the message.

Request

The action posts the payload with a timeout of 10 seconds, and verifies SSL certificates.

The request runs in the background. The action always reports success to the content rules engine, so the remaining actions of the rule run, whether Slack accepts the message or not. Failures are logged, as described in Logging.