@atomist/slack-messages

Node.js module that helps to create well-formatted Slack messages sent through the @atomist bot from your software delivery machine (SDM). This module also facilitates adding actions to your Slack messages that execute SDM commands.

Support for sending Slack Block messages is also supported.

See the Atomist documentation for more information on what SDMs are and what they can do for you using the Atomist API for software.

Using

Construct a message as a plain map following the Slack message formatting API.

import { SlackMessage } from "@atomist/slack-messages";
// A very simple message
const msg: SlackMessage = { text: "Simple message" };

import {
    escape,
    SlackMessage,
    url,
} from "@atomist/slack-messages";
// Here is an example of a message with a Slack action (button).
const msg: SlackMessage = {
    text: `${url(user.url, "@" + user.name)} opened issue: ${url(issue.url, issue.title)}`,
    attachments: [
        {
            text: escape(issue.body),
            fallback: escape(issue.title),
            mrkdwn_in: ["text"],
            actions: [
                {
                    text: "Close issue",
                    type: "button",
                    name: "closeissue",
                    value: "somebuttonid",
                },
            ],
            callback_id: "cllbck1",
        },
    ],
};

And then render the message with render(msg). This will construct a JSON string representation of the message:

import { render } from "@atomist/slack-messages"

const renderedMsg = render(msg);

or to produce a pretty JSON string:

const renderedMsg = render(msg, true);

This will produce the following JSON string (pretty version):

{
  "text": "<https://github.com/anna|@anna> opened issue: <https://github.com/someorg/somerepo/issues/484|This issue title contains &lt;unsafe&gt; characters and &amp;>",
  "attachments": [
    {
      "text": "This is a very important issue with body containing &lt;unsafe&gt; characters and even &amp;",
      "fallback": "This issue title contains &lt;unsafe&gt; characters and &amp;",
      "mrkdwn_in": [
        "text"
      ],
      "callback_id": "cllbck1",
      "actions": [
        {
          "text": "Close issue",
          "type": "button",
          "name": "rug",
          "value": "somebuttonid"
        }
      ]
    }
  ]
}

Note that the render function will automatically assign a unique callback_id to each attachments that has actions. But, if you provide your custom callback_id it will be preserved as is.

Additional helper functions

Special characters

escape("Slack requires you to escape <, > and &");
// => "Slack requires you to escape &lt;, &gt; and &amp;"

Links

// Simple link
url("https://www.atomist.com");
// => "<https://www.atomist.com>"

// Link with label
url("https://www.atomist.com", "atomist");
// => "<https://www.atomist.com|atomist>"

User & channel links

// @some-user (Slack will display user name for provided user ID)
user("U123");
// => "<@U123>"

// #some-channel (Slack will display channel name for provided channel ID)
channel("C123");
// => "<#C123>"

Special variables

// @channel
atChannel();
// => "<!channel>"

// @here
atHere();
// => "<!here>"

// @everyone
atEveryone();
// => "<!everyone>"

Emoji

emoji("smile");
// => ":smile:";

Markdown

Slack will render markdown if field where markdown is present is included in mrkdwn_in array.

bold("This text will appear bold");
// => "*This text will appear bold*"

italic("This text will appear italic");
// => "_This text will appear italic_"

strikethrough("This text will appear strike-through");
// => "~This text will appear strike-through~"

// Single line code block
codeLine("var a = new A();");
// =>  "`var a = new A();`"

// Multi line code block
codeBlock("var a = new A();\nvar b = new B();");
// => "```var a = new A();\nvar b = new B();```"

// List
listItem("Item 1");
// => "• Item 1"

GitHub to Slack markdown conversion

GitHub and Slack markdown are different enough to make your GitHub issues or GitHub PRs look quite bad in Slack by default. You can use the githubToSlack function from Markdown to convert text that uses GitHub markdown to text that will look good in Slack:

import { githubToSlack } from "@atomist/slack-messages"

githubToSlack("* list item 1\n* list item 2\n\**some bold text** and *some italic text* with a link [click here](http://someplace.com)");
// => "• list item 1\n• list item 2\n*some bold text* and _some italic text_ with a link <http://someplace.com|click here>"