feat: memcached instrumentation (open-telemetry#539)

.github/workflows/unit-test.yml

@@ -14,10 +14,28 @@ jobs:
     container:
       image: ${{ matrix.container }}
     services:
+      memcached:
+        image: memcached:1.6.9-alpine
+        ports:
+        - 11211:11211
       mongo:
         image: mongo
         ports:
         - 27017:27017
+      mysql:
+        image: circleci/mysql:5.7
+        env:
+          MYSQL_USER: otel
+          MYSQL_PASSWORD: secret
+          MYSQL_DATABASE: circle_database
+          MYSQL_ROOT_PASSWORD: rootpw
+        ports:
+        - 3306:3306
+        options: >-
+          --health-cmd="mysqladmin ping"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
       postgres:
         image: circleci/postgres:9.6-alpine
         env:
@@ -39,25 +57,14 @@ jobs:
           --health-interval 10s
           --health-timeout 5s
           --health-retries 5
-      mysql:
-        image: circleci/mysql:5.7
-        env:
-          MYSQL_USER: otel
-          MYSQL_PASSWORD: secret
-          MYSQL_DATABASE: circle_database
-          MYSQL_ROOT_PASSWORD: rootpw
-        ports:
-        - 3306:3306
-        options: >-
-          --health-cmd="mysqladmin ping"
-          --health-interval 10s
-          --health-timeout 5s
-          --health-retries 5
     env:
-      RUN_POSTGRES_TESTS: 1
-      RUN_MYSQL_TESTS: 1
+      RUN_MEMCACHED_TESTS: 1
       RUN_MONGODB_TESTS: 1
+      RUN_MYSQL_TESTS: 1
+      RUN_POSTGRES_TESTS: 1
       RUN_REDIS_TESTS: 1
+      OPENTELEMETRY_MEMCACHED_HOST: memcached
+      OPENTELEMETRY_MEMCACHED_PORT: 11211
       POSTGRES_USER: postgres
       POSTGRES_DB: circle_database
       POSTGRES_HOST: postgres

examples/memcached/README.md

@@ -0,0 +1,18 @@
+# Overview
+
+OpenTelemetry Memcached instrumentation allows user to automatically collect trace data from queries made by the client and export them to the backend of choice. This example does not showcase export functionality, but there are numerous other examples doing that: [`express`](../express), [`router`](../router).
+
+## Running the Example
+
+Created spans are printed out to stdout while running the example.
+
+```sh
+npm install # install the dependencies
+npm run docker:start # start memcached server
+npm run start # run the example
+npm run docker:stop # spin down and clean up the docker container
+```
+
+## LICENSE
+
+Apache License 2.0

examples/memcached/index.js

@@ -0,0 +1,20 @@
+'use strict';
+
+require('./tracer')('example-resource');
+const Memcached = require('memcached');
+const assert = require('assert');
+
+const KEY = '_KEY_';
+const VALUE = `RAND:${Math.random().toFixed(4)}`;
+const LT = 10;
+const client = new Memcached();
+
+client.set(KEY, VALUE, LT, (err) => {
+  assert.strictEqual(err, undefined);
+  client.get(KEY, (err, result) => {
+    assert.strictEqual(err, undefined);
+    assert.strictEqual(result, VALUE);
+    console.log('Sleeping 5 seconds before shutdown to ensure all records are flushed.');
+    setTimeout(() => { console.log('Completed.'); }, 5000);
+  });
+});

examples/memcached/package.json

@@ -0,0 +1,39 @@
+{
+  "name": "memcached-example",
+  "private": true,
+  "version": "0.22.0",
+  "description": "Example of Memcached client with OpenTelemetry",
+  "main": "index.js",
+  "scripts": {
+    "docker:start": "docker run --rm -d --name otel-memcached -p 11211:11211 memcached:1.6.9-alpine",
+    "docker:stop": "docker rm -f otel-memcached",
+    "start": "node index.js"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+ssh://[email protected]/open-telemetry/opentelemetry-js-contrib.git"
+  },
+  "keywords": [
+    "opentelemetry",
+    "instrumentation",
+    "memcached",
+    "tracing"
+  ],
+  "engines": {
+    "node": ">=8.5.0"
+  },
+  "author": "OpenTelemetry Authors",
+  "license": "Apache-2.0",
+  "bugs": {
+    "url": "https://github.com/open-telemetry/opentelemetry-js-contrib/issues"
+  },
+  "dependencies": {
+    "@opentelemetry/api": "^1.0.1",
+    "@opentelemetry/instrumentation": "^0.22.0",
+    "@opentelemetry/instrumentation-memcached": "^0.22.0",
+    "@opentelemetry/node": "^0.22.0",
+    "@opentelemetry/tracing": "^0.22.0",
+    "memcached": "^2.2.2"
+  },
+  "homepage": "https://github.com/open-telemetry/opentelemetry-js-contrib#readme"
+}

examples/memcached/tracer.js

@@ -0,0 +1,37 @@
+'use strict';
+
+const opentelemetry = require('@opentelemetry/api');
+
+const { diag, DiagConsoleLogger, DiagLogLevel } = opentelemetry;
+diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.VERBOSE);
+
+const { registerInstrumentations } = require('@opentelemetry/instrumentation');
+const { NodeTracerProvider } = require('@opentelemetry/node');
+const { SimpleSpanProcessor, ConsoleSpanExporter } = require('@opentelemetry/tracing');
+const { Resource } = require('@opentelemetry/resources');
+const { ResourceAttributes } = require('@opentelemetry/semantic-conventions');
+
+const { MemcachedInstrumentation } = require('@opentelemetry/instrumentation-memcached');
+
+module.exports = (serviceName) => {
+  const provider = new NodeTracerProvider({
+    resource: new Resource({
+      [ResourceAttributes.SERVICE_NAME]: serviceName,
+    }),
+  });
+  registerInstrumentations({
+    tracerProvider: provider,
+    instrumentations: [
+      new MemcachedInstrumentation(),
+    ],
+  });
+
+  const exporter = new ConsoleSpanExporter();
+
+  provider.addSpanProcessor(new SimpleSpanProcessor(exporter));
+
+  // Initialize the OpenTelemetry APIs to use the NodeTracerProvider bindings
+  provider.register();
+
+  return opentelemetry.trace.getTracer('memcached-example');
+};

packages/opentelemetry-test-utils/testUtils.ts

@@ -29,23 +29,18 @@ import {
   hrTimeToMicroseconds,
 } from '@opentelemetry/core';
 
-export function startDocker(db: 'redis' | 'mysql' | 'postgres') {
-  let dockerRunCmd;
-  switch (db) {
-    case 'redis':
-      dockerRunCmd = `docker run -d -p 63790:6379 --name ot${db} ${db}:alpine`;
-      break;
-
-    case 'mysql':
-      dockerRunCmd = `docker run --rm -d -e MYSQL_ROOT_PASSWORD=rootpw -e MYSQL_DATABASE=test_db -e MYSQL_USER=otel -e MYSQL_PASSWORD=secret -p 33306:3306 --name ot${db} circleci/${db}:5.7`;
-      break;
-
-    case 'postgres':
-      dockerRunCmd = `docker run -d -p 54320:5432 -e POSTGRES_PASSWORD=postgres --name ot${db} ${db}:alpine`;
-      break;
-  }
+const dockerRunCmds = {
+  redis: 'docker run --rm -d --name otel-redis -p 63790:6379 redis:alpine',
+  mysql:
+    'docker run --rm -d --name otel-mysql -p 33306:3306 -e MYSQL_ROOT_PASSWORD=rootpw -e MYSQL_DATABASE=test_db -e MYSQL_USER=otel -e MYSQL_PASSWORD=secret circleci/mysql:5.7',
+  postgres:
+    'docker run --rm -d --name otel-postgres -p 54320:5432 -e POSTGRES_PASSWORD=postgres postgres:alpine',
+  memcached:
+    'docker run --rm -d --name otel-memcached -p 11211:11211 memcached:1.6.9-alpine',
+};
 
-  const tasks = [run(dockerRunCmd)];
+export function startDocker(db: keyof typeof dockerRunCmds) {
+  const tasks = [run(dockerRunCmds[db])];
 
   for (let i = 0; i < tasks.length; i++) {
     const task = tasks[i];
@@ -58,9 +53,9 @@ export function startDocker(db: 'redis' | 'mysql' | 'postgres') {
   return true;
 }
 
-export function cleanUpDocker(db: 'redis' | 'mysql' | 'postgres') {
-  run(`docker stop ot${db}`);
-  run(`docker rm ot${db}`);
+export function cleanUpDocker(db: keyof typeof dockerRunCmds) {
+  run(`docker stop otel-${db}`);
+  run(`docker rm otel-${db}`);
 }
 
 function run(cmd: string) {

plugins/node/opentelemetry-instrumentation-memcached/.eslintignore

@@ -0,0 +1 @@
+build

plugins/node/opentelemetry-instrumentation-memcached/.eslintrc.js

@@ -0,0 +1,7 @@
+module.exports = {
+    "env": {
+        "mocha": true,
+        "node": true
+    },
+    ...require('../../../eslint.config.js')
+}

plugins/node/opentelemetry-instrumentation-memcached/.npmignore

@@ -0,0 +1,4 @@
+/bin
+/coverage
+/doc
+/test