Codes: request telemetry in its own table, 30-day retention (#81)

ddiff --git a/migrations/0006_telemetry.sql b/migrations/0006_telemetry.sql
nnew file mode 100644
iindex 0000000..14260fa
---- /dev/null
++++ b/migrations/0006_telemetry.sql
@@@ -0,0 +1,28 @@
++-- phase: expand
++-- Request telemetry (openvibe-sdk/telemetry telemetrySchema()): one row per aggregated sample, pruned after 30 days (server/index.js).
++CREATE TABLE IF NOT EXISTS telemetry_samples (
++    id                    bigint GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
++    at                    timestamptz NOT NULL,
++    service               text NOT NULL,
++    project               text,
++    subject               text,
++    resource              text,
++    provider              text,
++    node                  text,
++    cell                  text,
++    region                text,
++    operation             text NOT NULL,
++    latency_ms            double precision,
++    queue_delay_ms        double precision,
++    ttfb_ms               double precision,
++    throughput_per_second double precision,
++    bytes                 bigint,
++    status                text,
++    cache_status          text,
++    cost_estimate         double precision,
++    route_epoch           bigint,
++    trace_id              text,
++    extra                 jsonb NOT NULL DEFAULT '{}'::jsonb
++);
++CREATE INDEX IF NOT EXISTS telemetry_samples_at_idx ON telemetry_samples (at);
++CREATE INDEX IF NOT EXISTS telemetry_samples_service_idx ON telemetry_samples (service, operation, at);
ddiff --git a/server/app.js b/server/app.js
iindex f53cd6e..dfcb547 100644
---- a/server/app.js
++++ b/server/app.js
@@@ -63,6 +63,7 @@ async function createApp(opts = {}) {
      const release = require('openvibe-shared/release').createRelease({ service: 'codes', root: path.join(__dirname, '..') });
      require('./render/layout').setRelease(release.release);
      const metrics = require('openvibe-shared/metrics').instrument(app, { service: 'codes', release: release.release });
++    app.use(require('openvibe-sdk/service').telemetryMiddleware);   // request telemetry: a no-op until server/index.js calls telemetry.init()
      app.locals.metrics = metrics.registry;
      app.locals.ctx = ctx;
      // Per-actor limits (http/actor-limits.js) at /api/v1, counted once the caller is known; the per-address
ddiff --git a/server/index.js b/server/index.js
iindex 18c10c3..911b787 100644
---- a/server/index.js
++++ b/server/index.js
@@@ -5,7 +5,8 @@
   * Listens on PORT (4900) behind nginx (deploy/).
   */
  const { createApp } = require('./app');
--const { gracefulStop } = require('openvibe-sdk/service');
++const { gracefulStop, telemetry } = require('openvibe-sdk/service');
++const { createPgTelemetrySink, startTelemetryRetention } = require('openvibe-sdk/telemetry');
  const { startSubscriptions } = require('openvibe-sdk/account-data');
  
  /**
@@@ -16,7 +17,7 @@ const { startSubscriptions } = require('openvibe-sdk/account-data');
  function createLifecycle({ server, ctx, exit, signals }) {
      return gracefulStop({
          name: 'Codes', server, deadlineExitCode: 0, exit, signals,
--        close: [() => ctx.keys.client.stop(), () => ctx.store.close()],
++        close: [() => ctx.keys.client.stop(), async () => { if (ctx.telemetryRetention) await ctx.telemetryRetention.stop(); await telemetry.stop(); }, () => ctx.store.close()],
      });
  }
  
@@@ -29,6 +30,10 @@ async function start() {
          console.log(`[Codes] ${ctx.harnesses.list().length} harnesses in the catalog; the developer console's addresses redirect to openvibe.services`);
      });
      server.keepAliveTimeout = 65_000;
++    // Request telemetry (openvibe-sdk/service, plan T1): one aggregated sample per route template, method and status
++    // class each 15 s, stored in this service's telemetry_samples table; rows older than 30 days go daily.
++    telemetry.init({ service: 'codes', sink: createPgTelemetrySink({ db: ctx.store.db, log: console }), skipPrefixes: ['/shared'] });
++    ctx.telemetryRetention = startTelemetryRetention({ db: ctx.store.db, log: console });
      // Keep the JWKS cache fresh in the background (openvibe-sdk/auth): one client per URL, the last
      // good keys through outages, exponential backoff, unknown-kid floods throttled, an unref'd timer.
      ctx.keys.client.start();
ddiff --git a/test/telemetry.test.js b/test/telemetry.test.js
nnew file mode 100644
iindex 0000000..76e7ba6
---- /dev/null
++++ b/test/telemetry.test.js
@@@ -0,0 +1,50 @@
++'use strict';
++/**
++ * Request telemetry (openvibe-sdk/service, plan T1 step 10): app.js mounts the process-wide telemetryMiddleware (a no-op
++ * until init), server/index.js calls telemetry.init() for service 'codes' with a PostgreSQL sink, starts the 30-day
++ * retention and flushes on stop. Five hits on one route flush as ONE aggregated http.request sample; /metrics and
++ * /shared make none; the retention deletes only rows older than 30 days.
++ */
++const assert = require('assert');
++const fs = require('fs');
++const path = require('path');
++const { telemetry } = require('openvibe-sdk/service');
++const { pruneTelemetry } = require('openvibe-sdk/telemetry');
++const { boot } = require('./helpers/boot');
++(async () => {
++    const read = (p) => fs.readFileSync(path.join(__dirname, '..', p), 'utf8');
++    assert.match(read('server/index.js'), /telemetry\.init\(\{ service: 'codes', sink: createPgTelemetrySink\(/, 'index.js starts the collector');
++    assert.match(read('server/index.js'), /startTelemetryRetention\(/, 'index.js starts the retention');
++    assert.match(read('server/index.js'), /[Rr]etention\.stop\(\); await telemetry\.stop\(\);/, 'the stop flushes');
++
++    const t = await boot();
++    const samples = [];
++    telemetry.init({ service: 'codes', sink: async (batch) => { samples.push(...batch); }, intervalMs: 3600e3 });
++    const requests = () => samples.filter((s) => s.operation === 'http.request');
++    try {
++        for (let i = 0; i < 5; i++) assert.strictEqual((await t.get('/')).status, 200);
++        await telemetry.flush();
++        const hit = requests().filter((s) => s.resource === '/' && s.status === '2xx');
++        assert.strictEqual(hit.length, 1, JSON.stringify(requests()));
++        assert.strictEqual(hit[0].service, 'codes');
++        assert.strictEqual(hit[0].extra.count, 5);
++
++        samples.length = 0;
++        await await t.get('/metrics');
++        await await t.get('/shared/navbar.js');
++        await telemetry.flush();
++        assert.deepStrictEqual(requests(), [], '/metrics and /shared make no sample');
++
++        const db = t.ctx.store.db;
++        await db.query('DELETE FROM telemetry_samples');
++        const insert = (days) => db.query("INSERT INTO telemetry_samples (at, service, operation) VALUES (now() - make_interval(days => $1), 'codes', 'http.request')", [days]);
++        await insert(45);
++        await insert(1);
++        assert.strictEqual(await pruneTelemetry({ db }), 1);
++        assert.strictEqual((await db.query('SELECT count(*)::int AS n FROM telemetry_samples')).rows[0].n, 1);
++        console.log('telemetry ok');
++    } finally {
++        await telemetry.stop();
++        await t.close();
++    }
++})().catch((err) => { console.error(err); process.exit(1); });