(core) Fix flyctl cleanup; move/copy scripts to support preview deploys in grist-core

Summary:
- Fly flyctl cleanup which has been failing; deleting volumes before app no longer seems needed
- Move fly-deploy and add workflow scripts to make fly preview work in grist-core too

Test Plan: Tested that previews still work in this repo; and tested with a copy in grist-core.

Reviewers: jarek

Reviewed By: jarek

Subscribers: jarek

Differential Revision: https://phab.getgrist.com/D3928

.github/workflows/fly-cleanup.yml

@@ -0,0 +1,23 @@
+name: Fly Cleanup
+on:
+  schedule:
+    # Once a day, clean up jobs marked as expired
+    - cron: '50 12 * * *'
+
+  # Allows running this workflow manually from the Actions tab
+  workflow_dispatch:
+
+env:
+  FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}
+
+jobs:
+  clean:
+      name: Clean stale deployed apps
+      runs-on: ubuntu-latest
+      if: github.repository_owner == 'gristlabs'
+      steps:
+        - uses: actions/checkout@v3
+        - uses: superfly/flyctl-actions/setup-flyctl@master
+          with:
+            version: 0.0.525
+        - run: node buildtools/fly-deploy.js clean

.github/workflows/fly.yml

@@ -0,0 +1,64 @@
+name: Fly Deploy
+on:
+  pull_request:
+    branches: [ main ]
+    types: [labeled, unlabeled, closed, opened, synchronize, reopened]
+
+  # Allows running this workflow manually from the Actions tab
+  workflow_dispatch:
+
+env:
+  FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}
+  BRANCH_NAME: ${{ github.head_ref || github.ref_name }}
+
+jobs:
+  deploy:
+    name: Deploy app
+    runs-on: ubuntu-latest
+    # Deploy when the 'preview' label is added, or when PR is updated with this label present.
+    if: |
+          github.repository_owner == 'gristlabs' &&
+          github.event_name == 'pull_request' && (
+            github.event.action == 'labeled' ||
+            github.event.action == 'opened' ||
+            github.event.action == 'synchronize' ||
+            github.event.action == 'reopened'
+          ) &&
+          contains(github.event.pull_request.labels.*.name, 'preview')
+    steps:
+      - uses: actions/checkout@v3
+      - uses: superfly/flyctl-actions/setup-flyctl@master
+        with:
+          version: 0.0.525
+      - id: fly_deploy
+        run: |
+          node buildtools/fly-deploy.js deploy
+          flyctl config -c ./fly.toml env | awk '/APP_HOME_URL/{print "DEPLOY_URL=" $2}' >> $GITHUB_OUTPUT
+          flyctl config -c ./fly.toml env | awk '/FLY_DEPLOY_EXPIRATION/{print "EXPIRES=" $2}' >> $GITHUB_OUTPUT
+
+      - uses: actions/github-script@v6
+        with:
+          script: |
+            github.rest.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: `Deployed as ${{ steps.fly_deploy.outputs.DEPLOY_URL }} (until ${{ steps.fly_deploy.outputs.EXPIRES }})`
+            })
+
+  destroy:
+    name: Remove app
+    runs-on: ubuntu-latest
+    # Remove the deployment when 'preview' label is removed, or the PR is closed.
+    if: |
+          github.repository_owner == 'gristlabs' &&
+          github.event_name == 'pull_request' &&
+          (github.event.action == 'closed' ||
+           (github.event.action == 'unlabeled' && github.event.label.name == 'preview'))
+    steps:
+      - uses: actions/checkout@v3
+      - uses: superfly/flyctl-actions/setup-flyctl@master
+        with:
+          version: 0.0.525
+      - id: fly_destroy
+        run: node buildtools/fly-deploy.js destroy

buildtools/fly-deploy.js

@@ -0,0 +1,142 @@
+const util = require('util');
+const childProcess = require('child_process');
+const fs = require('fs/promises');
+const {existsSync} = require('fs');
+
+const exec = util.promisify(childProcess.exec);
+
+const org = "grist-labs";
+const expirationSec = 30 * 24 * 60 * 60;  // 30 days
+
+const getAppName = () => "grist-" + getBranchName().toLowerCase().replace(/[\W|_]+/g, '-');
+const getVolumeName = () => "grist_vol_" + getBranchName().toLowerCase().replace(/\W+/g, '_');
+
+const getBranchName = () => {
+  if (!process.env.BRANCH_NAME) { console.log('Usage: Need BRANCH_NAME env var'); process.exit(1); }
+  return process.env.BRANCH_NAME;
+}
+
+async function main() {
+  if (process.argv[2] === 'deploy') {
+    const appRoot = process.argv[3] || ".";
+    if (!existsSync(`${appRoot}/Dockerfile`)) {
+      console.log(`Dockerfile not found in appRoot of ${appRoot}`);
+      process.exit(1);
+    }
+
+    const name = getAppName();
+    const volName = getVolumeName();
+    if (!await appExists(name)) {
+      await appCreate(name);
+      await appScale(name);
+      await volCreate(name, volName);
+    } else {
+      // Check if volume exists, and create it if not. This is needed because there was an API
+      // change in flyctl (mandatory -y flag) and some apps were created without a volume.
+      if (!(await volList(name)).length) {
+        await volCreate(name, volName);
+      }
+    }
+    await prepConfig(name, appRoot, volName);
+    await appDeploy(name, appRoot);
+  } else if (process.argv[2] === 'destroy') {
+    const name = getAppName();
+    if (await appExists(name)) {
+      await appDestroy(name);
+    }
+  } else if (process.argv[2] === 'clean') {
+    const staleApps = await findStaleApps();
+    for (const appName of staleApps) {
+      await appDestroy(appName);
+    }
+  } else {
+    console.log(`Usage:
+  deploy [appRoot]:
+            create (if needed) and deploy fly app grist-{BRANCH_NAME}.
+            appRoot may specify the working directory that contains the Dockerfile to build.
+  destroy:  destroy fly app grist-{BRANCH_NAME}
+  clean:    destroy all grist-* fly apps whose time has come
+            (according to FLY_DEPLOY_EXPIRATION env var set at deploy time)
+
+  DRYRUN=1 in environment will show what would be done
+`);
+    process.exit(1);
+  }
+}
+
+const appExists = (name) => runFetch(`flyctl status -a ${name}`).then(() => true).catch(() => false);
+const appCreate = (name) => runAction(`flyctl apps create ${name} -o ${org}`);
+const appScale = (name) => runAction(`flyctl scale memory 1024 -a ${name}`);
+const volCreate = (name, vol) => runAction(`flyctl volumes create ${vol} -s 1 -r ewr -y -a ${name}`);
+const volList = (name) => runFetch(`flyctl volumes list -a ${name} -j`).then(({stdout}) => JSON.parse(stdout));
+const appDeploy = (name, appRoot) => runAction(`flyctl deploy ${appRoot} --remote-only`, {shell: true, stdio: 'inherit'});
+
+async function appDestroy(name) {
+  await runAction(`flyctl apps destroy ${name} -y`);
+}
+
+async function prepConfig(name, appRoot, volName) {
+  const configPath = `${appRoot}/fly.toml`;
+  const configTemplatePath = `${appRoot}/buildtools/fly-template.toml`;
+  const template = await fs.readFile(configTemplatePath, {encoding: 'utf8'});
+
+  // Calculate the time when we can destroy the app, used by findStaleApps.
+  const expiration = new Date(Date.now() + expirationSec * 1000).toISOString();
+  const config = template
+    .replace(/{APP_NAME}/g, name)
+    .replace(/{VOLUME_NAME}/g, volName)
+    .replace(/{FLY_DEPLOY_EXPIRATION}/g, expiration);
+  await fs.writeFile(configPath, config);
+}
+
+function runFetch(cmd) {
+  console.log(`Running: ${cmd}`);
+  return exec(cmd);
+}
+
+async function runAction(cmd) {
+  if (process.env.DRYRUN) {
+    console.log(`Would run: ${cmd}`);
+    return;
+  }
+  console.log(`Running: ${cmd}`);
+  const cp = childProcess.spawn(cmd, {shell: true, stdio: 'inherit'});
+  return new Promise((resolve, reject) => {
+    cp.on('error', reject);
+    cp.on('exit', function (code) {
+      if (code === 0) {
+        resolve();
+      } else {
+        reject(new Error(`exited with code ${code}`));
+      }
+    });
+  });
+}
+
+async function findStaleApps() {
+  const {stdout} = await runFetch(`flyctl apps list -j`);
+  const list = JSON.parse(stdout);
+  const appNames = [];
+  for (const app of list) {
+    if (app.Organization?.Slug !== org) {
+      continue;
+    }
+    const {stdout} = await runFetch(`flyctl config display -a ${app.Name}`);
+    const expiration = JSON.parse(stdout).env?.FLY_DEPLOY_EXPIRATION;
+    if (!expiration) {
+      continue;
+    }
+    const expired = (Date.now() > Number(new Date(expiration)));
+    if (isNaN(expired)) {
+      console.warn(`Skipping ${app.Name} with invalid expiration ${expiration}`);
+    } else if (!expired) {
+      console.log(`Skipping ${app.Name}; not reached expiration of ${expiration}`);
+    } else {
+      console.log(`Will clean ${app.Name}; expired at ${expiration}`);
+      appNames.push(app.Name);
+    }
+  }
+  return appNames;
+}
+
+main().catch(err => { console.warn("ERROR", err); process.exit(1); });

buildtools/fly-template.toml

@@ -0,0 +1,46 @@
+app = "{APP_NAME}"
+kill_signal = "SIGINT"
+kill_timeout = 5
+processes = []
+
+[env]
+  APP_DOC_URL="https://{APP_NAME}.fly.dev"
+  APP_HOME_URL="https://{APP_NAME}.fly.dev"
+  APP_STATIC_URL="https://{APP_NAME}.fly.dev"
+  GRIST_SINGLE_ORG="docs"
+  PORT = "8080"
+  FLY_DEPLOY_EXPIRATION = "{FLY_DEPLOY_EXPIRATION}"
+
+[experimental]
+  allowed_public_ports = []
+  auto_rollback = true
+
+[[services]]
+  http_checks = []
+  internal_port = 8080
+  processes = ["app"]
+  protocol = "tcp"
+  script_checks = []
+  [services.concurrency]
+    hard_limit = 25
+    soft_limit = 20
+    type = "connections"
+
+  [[services.ports]]
+    force_https = true
+    handlers = ["http"]
+    port = 80
+
+  [[services.ports]]
+    handlers = ["tls", "http"]
+    port = 443
+
+  [[services.tcp_checks]]
+    grace_period = "1s"
+    interval = "15s"
+    restart_limit = 0
+    timeout = "2s"
+
+[mounts]
+source="{VOLUME_NAME}"
+destination="/persist"