feat: send reminder comment to stale initial PRs

Turns out some of our users are confused why Greenkeeper is not enabled
for their repos and it turns out, it's because they never merged the
initial PR. With this, we send out a reminder comment on the PR so
people have a clearer understanding of what happens.

We don't nag them again once we reminded them for that repo. We also
don't comment on very old PRs, as this likely causes more problems for
our users then it does good (super outdated dependencies etc.)

Hope this helps a couple of users to run
Greenkeeper :)

content/stale-initial-pr-reminder.js

@@ -0,0 +1,14 @@
+const md = require('./template')
+
+module.exports = () => md`
+Hey there 👋,
+
+we noticed that this PR is not merged yet. Just to let you know _Greenkeeper will
+not be enabled_ and you won't receive updates for your dependencies, if you don't merge
+this PR.
+
+In case you don't want to enable Greenkeeper, just close or ignore this PR, we
+won't nag you again. ✌️
+
+Have a great day! 🌴
+`

couchdb/repositories/_design/open_initial_pr/views/open_initial_pr/map.js

@@ -0,0 +1,5 @@
+function (doc) {
+  if(doc.type === 'pr' && doc.initial && doc.state === 'open' && !doc.staleInitialPRReminder) {
+    emit(doc.createdAt);
+  }
+}

couchdb/repositories/_design/open_initial_pr/views/open_initial_pr/reduce

@@ -0,0 +1 @@
+_count

jobs/schedule-stale-initial-pr-reminders.js

@@ -0,0 +1,26 @@
+const dbs = require('./lib/dbs')
+
+module.exports = async function () {
+  const {repositories} = await dbs()
+  const minAgeInDays = 7
+  const maxAgeInDays = 14
+  const startDate = new Date(Date.now() - maxAgeInDays * 24 * 60 * 60 * 1000).toJSON()
+  const endDate = new Date(Date.now() - minAgeInDays * 24 * 60 * 60 * 1000).toJSON()
+
+  const stalePRs = await repositories.query('open_initial_pr', {
+    startkey: startDate,
+    endkey: endDate,
+    inclusive_end: true,
+    include_docs: true
+  })
+  return stalePRs.rows.map(function (row) {
+    return {
+      data: {
+        name: 'send-stale-initial-pr-reminder',
+        prNumber: row.doc.number,
+        repositoryId: row.doc.repositoryId,
+        accountId: row.doc.accountId
+      }
+    }
+  })
+}

jobs/send-stale-initial-pr-reminder.js

@@ -0,0 +1,40 @@
+const githubQueue = require('../lib/github-queue')
+const dbs = require('../lib/dbs')
+const upsert = require('../lib/upsert')
+const staleInitialPRReminderComment = require('../content/stale-initial-pr-reminder')
+
+module.exports = async function (
+  { prNumber, repositoryId, accountId }
+) {
+  accountId = String(accountId)
+  repositoryId = String(repositoryId)
+
+  const { installations, repositories } = await dbs()
+  const installation = await installations.get(accountId)
+  const repository = await repositories.get(repositoryId)
+  const installationId = installation.installation
+  const ghqueue = githubQueue(installationId)
+
+  if (repository.enabled) return
+
+  const [owner, repo] = repository.fullName.split('/')
+
+  const issue = await ghqueue.read(github => github.issues.get({
+    owner,
+    repo,
+    number: prNumber
+  }))
+
+  if (issue.state !== 'open' || issue.locked) return
+
+  await ghqueue.write(github => github.issues.createComment({
+    owner,
+    repo,
+    number: prNumber,
+    body: staleInitialPRReminderComment
+  }))
+
+  await upsert(repositories, repositoryId, {
+    staleInitialPRReminder: true
+  })
+}

test/jobs/send-stale-initial-pr-reminder.js

@@ -0,0 +1,149 @@
+const { test } = require('tap')
+const nock = require('nock')
+const worker = require('../../jobs/send-stale-initial-pr-reminder')
+const upsert = require('../../lib/upsert')
+
+const dbs = require('../../lib/dbs')
+
+const waitFor = (milliseconds) => {
+  return new Promise((resolve) => {
+    setTimeout(resolve, milliseconds)
+  })
+}
+
+test('send-stale-initial-pr-reminder', async t => {
+  const { installations, repositories } = await dbs()
+
+  let githubNock
+
+  t.beforeEach(async () => {
+    githubNock = nock('https://api.github.com')
+      .post('/installations/37/access_tokens')
+      .reply(200, {
+        token: 'secret'
+      })
+      .get('/rate_limit')
+      .reply(200, {})
+
+    await installations.put({
+      _id: '123',
+      installation: 37
+    })
+
+    await repositories.put({
+      _id: '42',
+      accountId: '123',
+      enabled: false,
+      fullName: 'finnp/test'
+    })
+  })
+
+  t.afterEach(async () => {
+    nock.cleanAll()
+    await installations.remove(await installations.get('123'))
+    await repositories.remove(await repositories.get('42'))
+  })
+
+  t.test('send reminders for stale initial pr', async t => {
+    t.plan(2)
+
+    githubNock
+      .get('/repos/finnp/test/issues/1234')
+      .reply(200, {
+        state: 'open',
+        locked: false
+      })
+      .post('/repos/finnp/test/issues/1234/comments')
+      .reply(201, () => {
+        t.pass('comment added')
+        return {}
+      })
+
+    await worker({
+      prNumber: 1234,
+      repositoryId: 42,
+      accountId: 123
+    })
+
+    const repoDoc = await repositories.get('42')
+    t.ok(repoDoc.staleInitialPRReminder, 'staleInitialPRReminder set to true')
+    await waitFor(50)
+  })
+
+  t.test('does nothing if the repo is already enabled', async t => {
+    t.plan(1)
+
+    await upsert(repositories, '42', {enabled: true})
+
+    githubNock
+      .get('/repos/finnp/test/issues/1234')
+      .reply(200, () => {
+        t.fail('Should not query issue status')
+        return {}
+      })
+      .post('/repos/finnp/test/issues/1234/comments')
+      .reply(201, () => {
+        t.fail('Should not post comment')
+        return {}
+      })
+
+    const newJob = await worker({
+      prNumber: 1234,
+      repositoryId: 42,
+      accountId: 123
+    })
+
+    t.notOk(newJob, 'no new job')
+    await waitFor(50)
+  })
+
+  t.test('does nothing if the issue was closed in the meanwhile', async t => {
+    t.plan(1)
+
+    githubNock
+      .get('/repos/finnp/test/issues/1234')
+      .reply(200, {
+        state: 'closed',
+        locked: false
+      })
+      .post('/repos/finnp/test/issues/1234/comments')
+      .reply(201, () => {
+        t.fail('Should not post comment')
+        return {}
+      })
+
+    const newJob = await worker({
+      prNumber: 1234,
+      repositoryId: 42,
+      accountId: 123
+    })
+
+    t.notOk(newJob, 'no new job')
+    await waitFor(50)
+  })
+
+  t.test('does nothing if the issue was locked in the meanwhile', async t => {
+    t.plan(1)
+
+    githubNock
+      .get('/repos/finnp/test/issues/1234')
+      .reply(200, {
+        state: 'open',
+        locked: true
+      })
+      .post('/repos/finnp/test/issues/1234/comments')
+      .reply(201, () => {
+        t.fail('Should not post comment')
+        return {}
+      })
+
+    const newJob = await worker({
+      prNumber: 1234,
+      repositoryId: 42,
+      accountId: 123
+    })
+
+    t.notOk(newJob, 'no new job')
+    await waitFor(50)
+  })
+})