chore: moves express examples into its package to establish pattern

.github/workflows/unit-test.yml

@@ -199,6 +199,8 @@ jobs:
         run: npx lerna bootstrap --no-ci
       - name: Unit tests
         run: npm run test:browser
+      - name: Build examples
+        run: npm run --if-present compile:examples
       - name: Report Coverage
         uses: codecov/codecov-action@v2
         with:

examples/README.md

@@ -0,0 +1,42 @@
+# Instrumentation Examples
+
+:warning: Note: We are working on migrating these examples to their respective package directories.
+
+For instance, examples of using `express` instrumentation have moved from this directory to [plugins/node/opentelemetry-instrumentation-express](https://github.com/open-telemetry/opentelemetry-js/tree/main/plugins/node/opentelemetry-instrumentation-express).
+
+
+## Instructions for Migrating an Example
+
+* [ ] Move the files
+  * [ ] Choose an instrumentation package to migrate examples for.
+  * [ ] Move the examples from `./examples/[name]` to `./plugins/[node or web]]/opentelemetry-instrumentation-[name]/examples`.
+* [ ] Update the `package.json` in the examples folder
+  * [ ] Remove the `@opentelemetry/instrumentation-[name]` dependency.
+  * [ ] Install `typescript` and `ts-node` in the examples directory.
+  * [ ] Replace usage of `node` in scripts with `ts-node`.
+  * [ ] Add a script for compiling the code in scripts: `"compile": "tsc -p ."`
+* [ ] Add a tsconfig.json file in the examples folder. (Example below)
+* [ ] Update the code
+  * [ ] Change code to use a relative import of the library.
+  * [ ] Add types to the code
+* [ ] Update the instrumentation package's `package.json`
+  * [ ] Add a script `"compile:examples": "cd examples && npm run compile",`.
+* [ ] Test the updated code
+  * [ ] Test building the examples by running `npm run compile:examples`
+  * [ ] Test that the actual exapmle code runs as expected
+
+Example tsconfig.json file:
+
+```json
+{
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "noEmit": true,
+    "rootDir": ".",
+  },
+  "include": [
+    "src/**/*.ts",
+    "test/**/*.ts"
+  ]
+}
+```

plugins/node/opentelemetry-instrumentation-express/examples/package.json

@@ -0,0 +1,50 @@
+{
+  "name": "express-example",
+  "private": true,
+  "version": "0.28.0",
+  "description": "Example of Express integration with OpenTelemetry",
+  "main": "index.js",
+  "scripts": {
+    "zipkin:server": "cross-env EXPORTER=zipkin ts-node src/server.ts",
+    "zipkin:client": "cross-env EXPORTER=zipkin ts-node src/client.ts",
+    "jaeger:server": "cross-env EXPORTER=jaeger ts-node src/server.ts",
+    "jaeger:client": "cross-env EXPORTER=jaeger ts-node src/client.ts",
+    "compile": "tsc -p ."
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+ssh://[email protected]/open-telemetry/opentelemetry-js.git"
+  },
+  "keywords": [
+    "opentelemetry",
+    "express",
+    "tracing"
+  ],
+  "engines": {
+    "node": ">=8"
+  },
+  "author": "OpenTelemetry Authors",
+  "license": "Apache-2.0",
+  "bugs": {
+    "url": "https://github.com/open-telemetry/opentelemetry-js/issues"
+  },
+  "dependencies": {
+    "@opentelemetry/api": "^1.0.2",
+    "@opentelemetry/exporter-jaeger": "^0.26.0",
+    "@opentelemetry/exporter-zipkin": "^0.26.0",
+    "@opentelemetry/instrumentation": "^0.27.0",
+    "@opentelemetry/instrumentation-http": "^0.27.0",
+    "@opentelemetry/resources": "^0.26.0",
+    "@opentelemetry/sdk-trace-base": "^1.0.0",
+    "@opentelemetry/sdk-trace-node": "^0.26.0",
+    "@opentelemetry/semantic-conventions": "^0.26.0",
+    "axios": "^0.21.1",
+    "cross-env": "^7.0.3",
+    "express": "^4.17.1"
+  },
+  "homepage": "https://github.com/open-telemetry/opentelemetry-js#readme",
+  "devDependencies": {
+    "ts-node": "^10.6.0",
+    "typescript": "^4.6.2"
+  }
+}

examples/express/client.js → plugins/node/opentelemetry-instrumentation-express/examples/src/client.ts

@@ -1,9 +1,11 @@
 'use strict';
 
 // eslint-disable-next-line import/order
-const tracer = require('./tracer')('example-express-client');
-const api = require('@opentelemetry/api');
-const axios = require('axios').default;
+import { setupTracing } from "./tracer";
+const tracer = setupTracing('example-express-client');
+
+import * as api from '@opentelemetry/api';
+import { default as axios } from 'axios';
 
 function makeRequest() {
   const span = tracer.startSpan('client.makeRequest()', {
@@ -16,8 +18,10 @@ function makeRequest() {
       console.log('status:', res.statusText);
       span.setStatus({ code: api.SpanStatusCode.OK });
     } catch (e) {
-      console.log('failed:', e.message);
-      span.setStatus({ code: api.SpanStatusCode.ERROR, message: e.message });
+      if (e instanceof Error) {
+        console.log('failed:', e.message);
+        span.setStatus({ code: api.SpanStatusCode.ERROR, message: e.message });
+      }
     }
     span.end();
     console.log('Sleeping 5 seconds before shutdown to ensure all records are flushed.');

examples/express/server.js → plugins/node/opentelemetry-instrumentation-express/examples/src/server.ts

@@ -1,19 +1,19 @@
-'use strict';
+import { setupTracing } from './tracer'
 
-// eslint-disable-next-line
-require('./tracer')('example-express-server');
+setupTracing('example-express-server');
 
 // Require in rest of modules
-const express = require('express');
-const axios = require('axios').default;
+import * as express from 'express';
+import { default as axios } from 'axios';
+import { RequestHandler } from "express";
 
 // Setup express
 const app = express();
 const PORT = 8080;
 
 const getCrudController = () => {
   const router = express.Router();
-  const resources = [];
+  const resources: any[] = [];
   router.get('/', (req, res) => res.send(resources));
   router.post('/', (req, res) => {
     resources.push(req.body);
@@ -22,7 +22,7 @@ const getCrudController = () => {
   return router;
 };
 
-const authMiddleware = (req, res, next) => {
+const authMiddleware: RequestHandler = (req, res, next) => {
   const { authorization } = req.headers;
   if (authorization && authorization.includes('secret_token')) {
     next();

examples/express/tracer.js → plugins/node/opentelemetry-instrumentation-express/examples/src/tracer.ts

@@ -1,26 +1,28 @@
 'use strict';
 
+import { Sampler, SpanKind } from "@opentelemetry/api";
+
 const opentelemetry = require('@opentelemetry/api');
 
 // Not functionally required but gives some insight what happens behind the scenes
 const { diag, DiagConsoleLogger, DiagLogLevel } = opentelemetry;
 diag.setLogger(new DiagConsoleLogger(), DiagLogLevel.INFO);
 
-const { AlwaysOnSampler } = require('@opentelemetry/core');
-const { registerInstrumentations } = require('@opentelemetry/instrumentation');
-const { NodeTracerProvider } = require('@opentelemetry/sdk-trace-node');
-const { SimpleSpanProcessor } = require('@opentelemetry/sdk-trace-base');
-const { JaegerExporter } = require('@opentelemetry/exporter-jaeger');
-const { ZipkinExporter } = require('@opentelemetry/exporter-zipkin');
-const { Resource } = require('@opentelemetry/resources');
-const { SemanticAttributes, SemanticResourceAttributes: ResourceAttributesSC } = require('@opentelemetry/semantic-conventions');
+import { AlwaysOnSampler } from '@opentelemetry/core';
+import { registerInstrumentations } from '@opentelemetry/instrumentation';
+import { NodeTracerProvider } from '@opentelemetry/sdk-trace-node';
+import { SimpleSpanProcessor } from '@opentelemetry/sdk-trace-base';
+import { JaegerExporter } from '@opentelemetry/exporter-jaeger';
+import { ZipkinExporter } from '@opentelemetry/exporter-zipkin';
+import { Resource } from '@opentelemetry/resources';
+import { SemanticAttributes, SemanticResourceAttributes as ResourceAttributesSC } from '@opentelemetry/semantic-conventions';
+import { SpanAttributes } from "@opentelemetry/api/build/src/trace/attributes";
 
-const Exporter = (process.env.EXPORTER || '')
-  .toLowerCase().startsWith('z') ? ZipkinExporter : JaegerExporter;
-const { ExpressInstrumentation } = require('@opentelemetry/instrumentation-express');
+const Exporter = (process.env.EXPORTER || '').toLowerCase().startsWith('z') ? ZipkinExporter : JaegerExporter;
+const { ExpressInstrumentation } = require('../../src');
 const { HttpInstrumentation } = require('@opentelemetry/instrumentation-http');
 
-module.exports = (serviceName) => {
+export const setupTracing = (serviceName: string) => {
   const provider = new NodeTracerProvider({
     resource: new Resource({
       [ResourceAttributesSC.SERVICE_NAME]: serviceName,
@@ -45,10 +47,12 @@ module.exports = (serviceName) => {
   // Initialize the OpenTelemetry APIs to use the NodeTracerProvider bindings
   provider.register();
 
-  return opentelemetry.trace.getTracer('express-example');
+  return opentelemetry.trace.getTracer(serviceName);
 };
 
-function filterSampler(filterFn, parent) {
+type FilterFunction = (spanName: string, spanKind: SpanKind, attributes: SpanAttributes) => boolean;
+
+function filterSampler(filterFn: FilterFunction, parent: Sampler): Sampler {
   return {
     shouldSample(ctx, tid, spanName, spanKind, attr, links) {
       if (!filterFn(spanName, spanKind, attr)) {
@@ -62,6 +66,6 @@ function filterSampler(filterFn, parent) {
   }
 }
 
-function ignoreHealthCheck(spanName, spanKind, attributes) {
+function ignoreHealthCheck(spanName: string, spanKind: SpanKind, attributes: SpanAttributes) {
   return spanKind !== opentelemetry.SpanKind.SERVER || attributes[SemanticAttributes.HTTP_ROUTE] !== "/health";
 }

plugins/node/opentelemetry-instrumentation-express/examples/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "../tsconfig.json",
+  "compilerOptions": {
+    "noEmit": true,
+    "rootDir": ".",
+  },
+  "include": [
+    "src/**/*.ts",
+    "test/**/*.ts"
+  ]
+}

plugins/node/opentelemetry-instrumentation-express/package.json

@@ -16,6 +16,7 @@
     "prewatch": "npm run precompile",
     "version:update": "node ../../../scripts/version-update.js",
     "compile": "tsc -p .",
+    "compile:examples": "cd examples && npm run compile",
     "prepare": "npm run compile",
     "watch": "tsc -w"
   },