chore(examples): lint examples/koa using shared top-level eslint config (#2903)

Refs: #2891

Author: trentm

examples/koa/.eslintrc.js

@@ -0,0 +1,26 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+'use strict';
+
+const baseConfig = require('../../eslint.config');
+
+module.exports = {
+  ...baseConfig,
+  env: {
+    node: true,
+  },
+};

examples/koa/package.json

@@ -4,6 +4,8 @@
   "version": "0.1.0",
   "description": "Example of Koa and @koa/router integration with OpenTelemetry",
   "scripts": {
+    "lint": "eslint . --ext=ts,js,mjs",
+    "lint:fix": "eslint . --ext=ts,js,mjs --fix",
     "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",
@@ -37,6 +39,7 @@
     "@opentelemetry/instrumentation": "^0.48.0",
     "@opentelemetry/instrumentation-http": "^0.48.0",
     "@opentelemetry/instrumentation-koa": "^0.31.0",
+    "@opentelemetry/resources": "^1.0.0",
     "@opentelemetry/sdk-trace-node": "^1.0.0",
     "@opentelemetry/sdk-trace-base": "^1.0.0",
     "@opentelemetry/semantic-conventions": "^1.27.0",

examples/koa/src/client.ts

@@ -1,29 +1,55 @@
-'use strict';
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
-import { setupTracing } from "./tracer";
-const tracer = setupTracing('example-koa-client');
 import * as api from '@opentelemetry/api';
-import { default as axios } from 'axios';
+import * as axios from 'axios';
+// eslint-disable-next-line import/extensions
+import { setupTracing } from './tracer';
+
+const tracer = setupTracing('example-koa-client');
 
-function makeRequest() {
+async function makeRequest() {
   const span = tracer.startSpan('client.makeRequest()', {
     kind: api.SpanKind.CLIENT,
   });
 
-  api.context.with(api.trace.setSpan(api.ROOT_CONTEXT, span), async () => {
-    try {
-      const res = await axios.get('http://localhost:8081/run_test');
-      span.setStatus({ code: api.SpanStatusCode.OK });
-      console.log(res.statusText);
-    } catch (e) {
-      if(e instanceof Error) {
-        span.setStatus({ code: api.SpanStatusCode.ERROR, message: e.message });
+  await api.context.with(
+    api.trace.setSpan(api.ROOT_CONTEXT, span),
+    async () => {
+      try {
+        const res = await axios.get('http://localhost:8081/run_test');
+        span.setStatus({ code: api.SpanStatusCode.OK });
+        console.log(res.statusText);
+      } catch (e) {
+        if (e instanceof Error) {
+          span.setStatus({
+            code: api.SpanStatusCode.ERROR,
+            message: e.message,
+          });
+        }
       }
+      span.end();
+      console.log(
+        'Sleeping 5 seconds before shutdown to ensure all records are flushed.'
+      );
+      setTimeout(() => {
+        console.log('Completed.');
+      }, 5000);
     }
-    span.end();
-    console.log('Sleeping 5 seconds before shutdown to ensure all records are flushed.');
-    setTimeout(() => { console.log('Completed.'); }, 5000);
-  });
+  );
 }
 
-makeRequest();
+makeRequest().catch(err => console.log(err));

examples/koa/src/server.ts

@@ -1,21 +1,37 @@
-'use strict';
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
 import * as api from '@opentelemetry/api';
-import { setupTracing } from './tracer'
-setupTracing('example-koa-server');
 
 // Adding Koa router (if desired)
-import * as Router from "@koa/router";
-import * as Koa from "koa"
+import * as Router from '@koa/router';
+import * as Koa from 'koa';
+// eslint-disable-next-line import/extensions
+import { setupTracing } from './tracer';
 
+setupTracing('example-koa-server');
 
 // Setup koa
 const app = new Koa();
 const PORT = 8081;
 const router = new Router();
 
 // route definitions
-router.get('/run_test', runTest)
+router
+  .get('/run_test', runTest)
   .get('/post/new', addPost)
   .get('/post/:id', showNewPost);
 
@@ -26,15 +42,15 @@ async function setUp() {
 
 /**
  *  Router functions: list, add, or show posts
-*/
+ */
 const posts = ['post 0', 'post 1', 'post 2'];
 
 function addPost(ctx: Koa.Context) {
   const newPostId = posts.length;
   posts.push(`post ${newPostId}`);
   const currentSpan = api.trace.getSpan(api.context.active());
   currentSpan?.addEvent('Added post');
-  currentSpan?.setAttribute('post.id', newPostId)
+  currentSpan?.setAttribute('post.id', newPostId);
   ctx.body = `Added post: ${posts[posts.length - 1]}`;
   ctx.redirect('/post/3');
 }
@@ -45,14 +61,16 @@ async function showNewPost(ctx: Koa.Context) {
   const post = posts[id];
   if (!post) ctx.throw(404, 'Invalid post id');
   const syntheticDelay = 500;
-  await new Promise((r) => setTimeout(r, syntheticDelay));
+  await new Promise(r => {
+    setTimeout(r, syntheticDelay);
+  });
   ctx.body = post;
 }
 
 function runTest(ctx: Koa.Context) {
   console.log('runTest');
   const currentSpan = api.trace.getSpan(api.context.active());
-  if (currentSpan){
+  if (currentSpan) {
     const { traceId } = currentSpan.spanContext();
     console.log(`traceid: ${traceId}`);
     console.log(`Jaeger URL: http://localhost:16686/trace/${traceId}`);
@@ -62,14 +80,15 @@ function runTest(ctx: Koa.Context) {
   }
 }
 
-async function noOp(ctx: Koa.Context, next: Koa.Next) {
+function noOp(ctx: Koa.Context, next: Koa.Next) {
   console.log('Sample basic koa middleware');
   const syntheticDelay = 100;
-  await new Promise((r) => setTimeout(r, syntheticDelay));
-  next();
+  setTimeout(next, syntheticDelay);
 }
 
-setUp().then(() => {
-  app.listen(PORT);
-  console.log(`Listening on http://localhost:${PORT}`);
-});
+setUp()
+  .then(() => {
+    app.listen(PORT);
+    console.log(`Listening on http://localhost:${PORT}`);
+  })
+  .catch(err => console.log(err));

examples/koa/src/tracer.ts

@@ -1,4 +1,18 @@
-'use strict';
+/*
+ * Copyright The OpenTelemetry Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
 import { KoaInstrumentation } from '@opentelemetry/instrumentation-koa';
 import { HttpInstrumentation } from '@opentelemetry/instrumentation-http';
@@ -10,10 +24,11 @@ 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 { ATTR_SERVICE_NAME } from '@opentelemetry/semantic-conventions'
+import { ATTR_SERVICE_NAME } from '@opentelemetry/semantic-conventions';
 
 const EXPORTER = process.env.EXPORTER || '';
 
+// eslint-disable-next-line import/prefer-default-export
 export const setupTracing = (serviceName: string) => {
   let exporter;
   if (EXPORTER === 'jaeger') {
@@ -24,18 +39,13 @@ export const setupTracing = (serviceName: string) => {
 
   const provider = new NodeTracerProvider({
     resource: new Resource({
-      [ATTR_SERVICE_NAME]: serviceName
+      [ATTR_SERVICE_NAME]: serviceName,
     }),
-    spanProcessors: [
-      new SimpleSpanProcessor(exporter),
-    ],
+    spanProcessors: [new SimpleSpanProcessor(exporter)],
   });
 
   registerInstrumentations({
-    instrumentations: [
-      new KoaInstrumentation(),
-      new HttpInstrumentation(),
-    ],
+    instrumentations: [new KoaInstrumentation(), new HttpInstrumentation()],
     tracerProvider: provider,
   });