feat: api metrics

.env.tpl

@@ -18,3 +18,4 @@ DATABASE_TOKEN=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJzdXBhYmFzZSIsImlh
 
 # Postgres Database
 DATABASE_CONNECTION=postgresql://postgres:postgres@localhost:5432/postgres
+RO_DATABASE_CONNECTION=postgresql://postgres:postgres@localhost:5432/postgres

.github/workflows/cron-metrics.yml

@@ -0,0 +1,39 @@
+name: Cron Metrics
+
+on:
+  schedule:
+    - cron: '*/20 * * * *'
+  workflow_dispatch:
+
+jobs:
+  update:
+    name: Calculate metrics
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        env: ['staging', 'production']
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+      - name: Checkout latest cron release tag
+        run: |
+          LATEST_TAG=$(git describe --tags --abbrev=0 --match='cron-*')
+          git checkout $LATEST_TAG
+      - uses: pnpm/action-setup@v2.0.1
+        with:
+          version: 6.32.x
+      - uses: actions/setup-node@v2
+        with:
+          node-version: 16
+      - run: pnpm install
+      - name: Run job
+        env:
+          DEBUG: '*'
+          ENV: ${{ matrix.env }}
+          STAGING_DATABASE_CONNECTION: ${{ secrets.STAGING_DATABASE_CONNECTION }}
+          STAGING_RO_DATABASE_CONNECTION: ${{ secrets.STAGING_DATABASE_CONNECTION }} # no replica for staging
+          PROD_DATABASE_CONNECTION: ${{ secrets.PROD_DATABASE_CONNECTION }}
+          PROD_RO_DATABASE_CONNECTION: ${{ secrets.PROD_RO_DATABASE_CONNECTION }}
+        run: pnpm --filter cron start

.github/workflows/cron.yml

@@ -0,0 +1,26 @@
+name: cron
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - 'packages/cron/**'
+      - '.github/workflows/cron.yml'
+  pull_request:
+    paths:
+      - 'packages/cron/**'
+      - '.github/workflows/cron.yml'
+release:
+  name: Release
+  runs-on: ubuntu-latest
+  needs: test
+  if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+  steps:
+    - uses: GoogleCloudPlatform/release-please-action@v3
+      id: tag-release
+      with:
+        path: packages/cron
+        token: ${{ secrets.GITHUB_TOKEN }}
+        release-type: node
+        monorepo-tags: true
+        package-name: cron

packages/api/db/reset.sql

@@ -1,2 +1,3 @@
 DROP TABLE IF EXISTS perma_cache;
-DROP TABLE IF EXISTS perma_cache_event;
+DROP TABLE IF EXISTS perma_cache_event;
+DROP TABLE IF EXISTS metrics;

packages/api/db/tables.sql

@@ -43,3 +43,12 @@ CREATE TABLE IF NOT EXISTS public.perma_cache_event
 );
 
 CREATE INDEX IF NOT EXISTS perma_cache_event_user_id_idx ON perma_cache_event (user_id);
+
+-- Metric contains the current values of collected metrics.
+CREATE TABLE IF NOT EXISTS metric
+(
+    name TEXT PRIMARY KEY,
+    value BIGINT NOT NULL,
+    inserted_at TIMESTAMP WITH TIME ZONE DEFAULT timezone('utc'::text, now()) NOT NULL,
+    updated_at  TIMESTAMP WITH TIME ZONE DEFAULT timezone('utc'::text, now()) NOT NULL
+);

packages/api/src/constants.js

@@ -8,3 +8,5 @@ export const USER_TAGS = {
 export const MAX_ALLOWED_URL_LENGTH = 460
 
 export const HTTP_STATUS_CONFLICT = 409
+
+export const METRICS_CACHE_MAX_AGE = 10 * 60 // in seconds (10 minutes)

packages/api/src/index.js

@@ -7,8 +7,13 @@ import {
   withApiToken,
   withSuperHotAuthorized,
 } from './auth.js'
-import { permaCachePost, permaCacheListGet, permaCacheStatusGet, permaCacheDelete } from './perma-cache/index.js'
-
+import {
+  permaCachePost,
+  permaCacheListGet,
+  permaCacheStatusGet,
+  permaCacheDelete,
+} from './perma-cache/index.js'
+import { metricsGet } from './metrics.js'
 import { addCorsHeaders, withCorsHeaders } from './cors.js'
 import { errorHandler } from './error-handler.js'
 import { envAll } from './env.js'
@@ -24,6 +29,7 @@ const auth = {
 
 router
   .all('*', envAll)
+  .get('/metrics', withCorsHeaders(metricsGet))
   .get('/test', async (request, env, ctx) => {
     const r = await env.SUPERHOT.get('0.csv')
     return new Response(r.body)

packages/api/src/metrics.js

@@ -0,0 +1,50 @@
+/* global Response caches */
+
+import { METRICS_CACHE_MAX_AGE } from './constants.js'
+
+/**
+ * Retrieve metrics in prometheus exposition format.
+ * https://prometheus.io/docs/instrumenting/exposition_formats/
+ * @param {Request} request
+ * @param {import('./env').Env} env
+ * @param {import('./index').Ctx} ctx
+ * @returns {Promise<Response>}
+ */
+export async function metricsGet(request, env, ctx) {
+  const cache = caches.default
+  let res = await cache.match(request)
+  if (res) {
+    return res
+  }
+
+  const [usersTotal, urlsTotal, eventsTotal, sizeTotal] = await Promise.all([
+    env.db.getMetricsValue('users_total'),
+    env.db.getMetricsValue('urls_total'),
+    env.db.getMetricsValue('events_total'),
+    env.db.getMetricsValue('size_total'),
+  ])
+
+  const metrics = [
+    `# HELP nftlinkapi_permacache_urls_total Total perma cached urls.`,
+    `# TYPE nftlinkapi_permacache_urls_total counter`,
+    `nftlinkapi_permacache_urls_total ${urlsTotal}`,
+    `# HELP nftlinkapi_permacache_users_total Total number of users with perma cached urls.`,
+    `# TYPE nftlinkapi_permacache_users_total counter`,
+    `nftlinkapi_permacache_users_total ${usersTotal}`,
+    `# HELP nftlinkapi_permacache_size_total Total perma cached size.`,
+    `# TYPE nftlinkapi_permacache_size_total counter`,
+    `nftlinkapi_permacache_size_total ${sizeTotal}`,
+    `# HELP nftlinkapi_permacache_events_total Total perma cache events.`,
+    `# TYPE nftlinkapi_permacache_events_total counter`,
+    `nftlinkapi_permacache_events_total ${eventsTotal}`,
+  ].join('\n')
+
+  res = new Response(metrics, {
+    headers: {
+      'Cache-Control': `public, max-age=${METRICS_CACHE_MAX_AGE}`,
+    },
+  })
+  ctx.waitUntil(cache.put(request, res.clone()))
+
+  return res
+}

packages/api/src/utils/db-client.js

@@ -160,6 +160,26 @@ export class DBClient {
     return data || 0
   }
 
+  /**
+   * Get metrics for a given key.
+   *
+   * @param {string} key
+   */
+  async getMetricsValue(key) {
+    const query = this._client.from('metric')
+    const { data, error } = await query.select('value').eq('name', key)
+
+    if (error) {
+      throw new DBError(error)
+    }
+
+    if (!data || !data.length) {
+      return 0
+    }
+
+    return data[0].value
+  }
+
   /**
    * Get user by did
    *

packages/api/test/metrics.spec.js

@@ -0,0 +1,22 @@
+import test from 'ava'
+
+import { getMiniflare } from './scripts/utils.js'
+
+test.beforeEach((t) => {
+  // Create a new Miniflare environment for each test
+  t.context = {
+    mf: getMiniflare(),
+  }
+})
+
+test('Gets metrics content when empty state', async (t) => {
+  const { mf } = t.context
+
+  const response = await mf.dispatchFetch('https://localhost:8787/metrics')
+  const metricsResponse = await response.text()
+
+  t.is(metricsResponse.includes('nftlinkapi_permacache_urls_total 0'), true)
+  t.is(metricsResponse.includes('nftlinkapi_permacache_users_total 0'), true)
+  t.is(metricsResponse.includes('nftlinkapi_permacache_size_total 0'), true)
+  t.is(metricsResponse.includes('nftlinkapi_permacache_events_total 0'), true)
+})

packages/cron/README.md

@@ -0,0 +1,26 @@
+<h1 align="center">⁂<br/>nftstorage.link</h1>
+<p align="center">The cron jobs for housekeeping ✨</p>
+
+## Getting started
+
+Ensure you have all the dependencies, by running `pnpm i` in the root project.
+
+The following jobs are available:
+
+### metrics
+
+Verify that the following are set in the `.env` file in root of the project monorepo.
+
+```ini
+ENV=dev
+
+DATABASE_URL=http://localhost:3000
+DATABASE_TOKEN=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJzdXBhYmFzZSIsImlhdCI6MTYwMzk2ODgzNCwiZXhwIjoyNTUwNjUzNjM0LCJyb2xlIjoic2VydmljZV9yb2xlIn0.necIJaiP7X2T2QjGeV-FhpkizcNTX8HjDDBAxpgQTEI
+DATABASE_CONNECTION=postgres://postgres:postgres@127.0.0.1:5432/postgres
+```
+
+Run the job:
+
+```sh
+npm run start:metrics
+```

packages/cron/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "cron",
+  "version": "0.0.0",
+  "description": "nftstorage.link Cron Jobs",
+  "private": true,
+  "main": "src/index.js",
+  "type": "module",
+  "scripts": {
+    "start": "run-s start:*",
+    "start:metrics": "NODE_TLS_REJECT_UNAUTHORIZED=0 node src/bin/metrics.js"
+  },
+  "author": "Vasco Santos",
+  "license": "(Apache-2.0 OR MIT)",
+  "dependencies": {
+    "debug": "^4.3.1",
+    "dotenv": "^9.0.2",
+    "p-settle": "^5.0.0",
+    "pg": "^8.7.1"
+  },
+  "devDependencies": {
+    "npm-run-all": "^4.1.5"
+  }
+}

packages/cron/src/bin/metrics.js

@@ -0,0 +1,20 @@
+#!/usr/bin/env node
+
+import { updateMetrics } from '../jobs/metrics.js'
+import { envConfig } from '../lib/env.js'
+import { getPgPool } from '../lib/utils.js'
+
+async function main() {
+  const rwPg = getPgPool(process.env, 'rw')
+  const roPg = getPgPool(process.env, 'ro')
+
+  try {
+    await updateMetrics({ rwPg, roPg })
+  } finally {
+    await rwPg.end()
+    await roPg.end()
+  }
+}
+
+envConfig()
+main()