feat: Add support for library instrumentation (#631)

* feat: Add support for library instrumentation

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* fix lint error

* Remove redundant console log

* Address PR comments

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: losalex

handwritten/logging-bunyan/package.json

@@ -51,7 +51,7 @@
     "precompile": "gts clean"
   },
   "dependencies": {
-    "@google-cloud/logging": "^10.0.0",
+    "@google-cloud/logging": "^10.0.2",
     "google-auth-library": "^8.0.2"
   },
   "devDependencies": {

handwritten/logging-bunyan/src/index.ts

@@ -16,6 +16,11 @@
 
 import {Writable} from 'stream';
 import * as express from './middleware/express';
+import {
+  setInstrumentationStatus,
+  createDiagnosticEntry,
+} from '@google-cloud/logging/build/src/utils/instrumentation';
+import path = require('path');
 
 // Export the express middleware as 'express'.
 export {express};
@@ -64,6 +69,9 @@ export const LOGGING_SPAN_KEY = 'logging.googleapis.com/spanId';
  */
 export const LOGGING_SAMPLED_KEY = 'logging.googleapis.com/trace_sampled';
 
+// The variable to hold cached library version
+let libraryVersion: string;
+
 /**
  * Gets the current fully qualified trace ID when available from the
  * @google-cloud/trace-agent library in the LogEntry.trace field format of:
@@ -426,6 +434,24 @@ export class LoggingBunyan extends Writable {
    * @param callback The callback supplied by Writable.write
    */
   _writeCall(entries: Entry | Entry[], callback: Function) {
+    // First create instrumentation record if it is never written before
+    const alreadyWritten = setInstrumentationStatus(true);
+    if (!alreadyWritten) {
+      let instrumentationEntry = createDiagnosticEntry(
+        'nodejs-bunyan',
+        this.getNodejsLibraryVersion()
+      );
+      // Update instrumentation record resource and logName
+      instrumentationEntry.metadata.resource = this.resource;
+      instrumentationEntry.metadata.severity = 'INFO';
+      instrumentationEntry = (
+        this.redirectToStdout
+          ? (this.cloudLog as LogSync)
+          : (this.cloudLog as Log)
+      ).entry(instrumentationEntry.metadata, instrumentationEntry.data);
+      entries = Array.isArray(entries) ? entries : [entries];
+      entries.push(instrumentationEntry);
+    }
     if (this.redirectToStdout) {
       (this.cloudLog as LogSync).write(entries);
       // The LogSync class does not supports callback. However if callback provided and
@@ -435,6 +461,22 @@ export class LoggingBunyan extends Writable {
       (this.cloudLog as Log).write(entries, this.generateCallback(callback));
     }
   }
+
+  /**
+   * Method used to retrieve the current logging-bunyan library version
+   * @returns The version of this library
+   */
+  getNodejsLibraryVersion() {
+    if (libraryVersion) {
+      return libraryVersion;
+    }
+    libraryVersion = require(path.resolve(
+      __dirname,
+      '../../',
+      'package.json'
+    )).version;
+    return libraryVersion;
+  }
 }
 
 module.exports.BUNYAN_TO_STACKDRIVER = BUNYAN_TO_STACKDRIVER;

handwritten/logging-bunyan/system-test/logging-bunyan.ts

@@ -25,8 +25,10 @@ import {Logging, LogSync} from '@google-cloud/logging';
 const logging = new Logging();
 import {LoggingBunyan} from '../src/index';
 import delay from 'delay';
+import * as instrumentation from '@google-cloud/logging/build/src/utils/instrumentation';
 
 const WRITE_CONSISTENCY_DELAY_MS = 90000;
+const MESSAGE = 'Diagnostic test';
 
 const UUID = uuid.v4();
 function logName(name: string) {
@@ -55,6 +57,43 @@ describe('LoggingBunyan', function () {
     assert.ok(loggingBunyan.cloudLog instanceof LogSync);
   });
 
+  it('should write diagnostic entry', async () => {
+    instrumentation.setInstrumentationStatus(false);
+    const start = Date.now();
+    logger.info(MESSAGE);
+    const entries = await pollLogs(
+      LOG_NAME,
+      start,
+      2,
+      WRITE_CONSISTENCY_DELAY_MS
+    );
+    assert.strictEqual(entries.length, 2);
+    let isDiagnosticPresent = false;
+    entries.forEach(entry => {
+      assert.ok(entry.data);
+      if (
+        Object.prototype.hasOwnProperty.call(
+          entry.data,
+          instrumentation.DIAGNOSTIC_INFO_KEY
+        )
+      ) {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const info = (entry.data as any)[instrumentation.DIAGNOSTIC_INFO_KEY][
+          instrumentation.INSTRUMENTATION_SOURCE_KEY
+        ];
+        assert.equal(info[0].name, 'nodejs');
+        assert.ok(info[0].version.includes('.'));
+        assert.equal(info[1].name, 'nodejs-bunyan');
+        assert.ok(info[1].version.includes('.'));
+        isDiagnosticPresent = true;
+      } else {
+        const data = entry.data as {message: string};
+        assert.ok(data.message.includes(MESSAGE));
+      }
+    });
+    assert.ok(isDiagnosticPresent);
+  });
+
   it('should properly write log entries', async function () {
     this.retries(3);
     const timestamp = new Date();