uiur · April 18, 2019 00:24 · Apr 18, 2019
diff --git a/index.js b/index.js
@@ -0,0 +1,154 @@
+const axios = require('axios')
+const decode = require('decode-html')
+const CHANNEL = '#dev'
+const ISSUE_REPO = 'foo/bar'
+
+exports.otochan = (req, res) => {
+  console.log('Received request:', req.body)
+
+  // slack challenge
+  if (req.body.challenge) {
+    res.send(req.body.challenge)
+    return
+  }
+
+  // slack event
+  if (req.body.event) {
+    handleSlack(req, res)
+    return
+  }
+}
+
+function handleSlack(req, res) {
+  const event = req.body.event
+
+  if (event.type === 'reaction_added') {
+    if (event.reaction === 'イシュー') {
+      handleReaction(event)
+        .then(() => {
+          res.send('ok')
+        })
+        .catch(err => {
+          console.error(err)
+          res.status(500).send(err.message)
+        })
+
+      return
+    }
+  }
+
+  res.send('ok: no matched handler')
+}
+
+async function handleReaction(event) {
+  const { channel, ts } = event.item
+  const { messages } = await getMessages(channel, ts, 10)
+  const message = messages[0]
+  const permalink = await getPermalink(channel, message.ts)
+
+  const repo = ISSUE_REPO
+
+  const title = decode(message.text)
+  const historyText = messages.reverse()
+    .filter(m => m.type === 'message')
+    .map(m => decode(m.text))
+    .join("\n")
+
+  const body = `${permalink}\n` + '```\n' + historyText + '\n```'
+
+  const issues = await getLatestIssues(repo)
+  const foundIssue = issues.find((issue) => {
+    return issue.title === title
+  })
+
+  if (foundIssue) {
+    return
+  }
+
+  const issue = await createIssue(repo, { title: title, body: body })
+  const slackMessage = `<@${event.user}> ${issue.html_url}`
+  await postMessage(channel, slackMessage)
+}
+
+function apiHeaders(token) {
+  return {
+    'Content-Type': 'application/json',
+    'Authorization': `Bearer ${token}`
+  }
+}
+
+async function getMessages (channel, ts, count = 1) {
+  const token = process.env.SLACK_USER_TOKEN
+
+  const res = await axios.get('https://slack.com/api/channels.history', {
+    params: {
+      channel: channel,
+      latest: ts,
+      count: count,
+      inclusive: true,
+      token: token
+    }
+  })
+
+  return res.data
+}
+
+async function postMessage (channel, text) {
+  const token = process.env.SLACK_TOKEN
+
+  await axios.post('https://slack.com/api/chat.postMessage', {
+    channel: channel,
+    text: text,
+    icon_emoji: ':chicken:'
+  }, {
+    headers: apiHeaders(token)
+  })
+}
+
+async function getPermalink (channel, ts) {
+  const res = await axios.get('https://slack.com/api/chat.getPermalink', {
+    params: {
+      channel: channel,
+      message_ts: ts,
+      token: process.env.SLACK_TOKEN
+    }
+  })
+
+  return res.data.permalink
+}
+
+function githubApiHeaders() {
+  return {
+    ...apiHeaders(process.env.GITHUB_TOKEN),
+    'Accept': 'application/vnd.github.v3+json'
+  }
+}
+
+async function createIssue(repo, params) {
+  const res = await axios.post(`https://api.github.com/repos/${repo}/issues`, params, {
+    headers: githubApiHeaders()
+  })
+
+  if (res.status > 300) {
+    console.error(res.data)
+    throw new Error(res.data.message)
+  }
+
+  return res.data
+}
+
+async function getLatestIssues(repo) {
+  const res = await axios.get(`https://api.github.com/repos/${repo}/issues`, {
+    params: {
+      state: 'all'
+    },
+    headers: githubApiHeaders()
+  })
+
+  if (res.status > 300) {
+    console.error(res.data)
+    throw new Error(res.data.message)
+  }
+
+  return res.data
+}