talk/plugins/talk-plugin-slack-notifications/server/hooks.js

const fetch = require('node-fetch');
const {SLACK_WEBHOOK_URL, SLACK_WEBHOOK_TIMEOUT} = require('./config');
const debug = require('debug')('talk:plugin:slack-notifications');

// We don't add the hooks during _test_ as the Slack API is not available.
if (process.env.NODE_ENV === 'test') {
  return null;
}

module.exports = {
  RootMutation: {
    createComment: {
      async post(_, {input}, context, _info, result) {
        debug(`Posting notification to Slack webhook: ${SLACK_WEBHOOK_URL}`);
        const {
          comment: {
            body: text,
            created_at: createdAt
          }
        } = result;
        const username = context.user.username;
        process.nextTick(async () => {
          const response = await fetch(SLACK_WEBHOOK_URL, {
            method: 'POST',
            headers: {
              'Content-Type': 'application/json',
            },
            timeout: SLACK_WEBHOOK_TIMEOUT,
            body: JSON.stringify({
              attachments: [{
                text: text,
                footer: `Comment by ${username}`,
                ts: Math.floor(Date.parse(createdAt) / 1000),
              }]
            }),
          });
          if (!response.ok) {
            const responseText = await response.text();
            console.trace(`Posting to Slack failed with HTTP code ${response.status} and body '${responseText}'`);
          }
        });
        return result;
      },
    },
  },
};