add(telemetry): Add OTel logging for FileOperationEvent (#7082)

Co-authored-by: Shnatu <snatu@google.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

docs/telemetry.md

@@ -195,6 +195,20 @@ Logs are timestamped records of specific events. The following events are logged
     - `error_type` (if applicable)
     - `metadata` (if applicable, dictionary of string -> any)
 
+- `gemini_cli.file_operation`: This event occurs for each file operation.
+  - **Attributes**:
+    - `tool_name` (string)
+    - `operation` (string: "create", "read", "update")
+    - `lines` (int, if applicable)
+    - `mimetype` (string, if applicable)
+    - `extension` (string, if applicable)
+    - `programming_language` (string, if applicable)
+    - `diff_stat` (json string, if applicable): A JSON string with the following members:
+      - `ai_added_lines` (int)
+      - `ai_removed_lines` (int)
+      - `user_added_lines` (int)
+      - `user_removed_lines` (int)
+
 - `gemini_cli.api_request`: This event occurs when making a request to Gemini API.
   - **Attributes**:
     - `model`

packages/core/src/telemetry/constants.ts

@@ -24,7 +24,7 @@ export const EVENT_INVALID_CHUNK = 'gemini_cli.chat.invalid_chunk';
 export const EVENT_CONTENT_RETRY = 'gemini_cli.chat.content_retry';
 export const EVENT_CONTENT_RETRY_FAILURE =
   'gemini_cli.chat.content_retry_failure';
-
+export const EVENT_FILE_OPERATION = 'gemini_cli.file_operation';
 export const METRIC_TOOL_CALL_COUNT = 'gemini_cli.tool.call.count';
 export const METRIC_TOOL_CALL_LATENCY = 'gemini_cli.tool.call.latency';
 export const METRIC_API_REQUEST_COUNT = 'gemini_cli.api.request.count';

packages/core/src/telemetry/loggers.test.ts

@@ -29,6 +29,7 @@ import {
   EVENT_USER_PROMPT,
   EVENT_FLASH_FALLBACK,
   EVENT_MALFORMED_JSON_RESPONSE,
+  EVENT_FILE_OPERATION,
 } from './constants.js';
 import {
   logApiRequest,
@@ -39,6 +40,7 @@ import {
   logFlashFallback,
   logChatCompression,
   logMalformedJsonResponse,
+  logFileOperation,
 } from './loggers.js';
 import { ToolCallDecision } from './tool-call-decision.js';
 import {
@@ -50,8 +52,10 @@ import {
   FlashFallbackEvent,
   MalformedJsonResponseEvent,
   makeChatCompressionEvent,
+  FileOperationEvent,
 } from './types.js';
 import * as metrics from './metrics.js';
+import { FileOperation } from './metrics.js';
 import * as sdk from './sdk.js';
 import { vi, describe, beforeEach, it, expect } from 'vitest';
 import type { GenerateContentResponseUsageMetadata } from '@google/genai';
@@ -890,4 +894,62 @@ describe('loggers', () => {
       });
     });
   });
+
+  describe('logFileOperation', () => {
+    const mockConfig = {
+      getSessionId: () => 'test-session-id',
+      getTargetDir: () => 'target-dir',
+      getUsageStatisticsEnabled: () => true,
+      getTelemetryEnabled: () => true,
+      getTelemetryLogPromptsEnabled: () => true,
+    } as Config;
+
+    const mockMetrics = {
+      recordFileOperationMetric: vi.fn(),
+    };
+
+    beforeEach(() => {
+      vi.spyOn(metrics, 'recordFileOperationMetric').mockImplementation(
+        mockMetrics.recordFileOperationMetric,
+      );
+    });
+
+    it('should log a file operation event', () => {
+      const event = new FileOperationEvent(
+        'test-tool',
+        FileOperation.READ,
+        10,
+        'text/plain',
+        '.txt',
+        'typescript',
+      );
+
+      logFileOperation(mockConfig, event);
+
+      expect(mockLogger.emit).toHaveBeenCalledWith({
+        body: 'File operation: read. Lines: 10.',
+        attributes: {
+          'session.id': 'test-session-id',
+          'user.email': 'test-user@example.com',
+          'event.name': EVENT_FILE_OPERATION,
+          'event.timestamp': '2025-01-01T00:00:00.000Z',
+          tool_name: 'test-tool',
+          operation: 'read',
+          lines: 10,
+          mimetype: 'text/plain',
+          extension: '.txt',
+          programming_language: 'typescript',
+        },
+      });
+
+      expect(mockMetrics.recordFileOperationMetric).toHaveBeenCalledWith(
+        mockConfig,
+        'read',
+        10,
+        'text/plain',
+        '.txt',
+        'typescript',
+      );
+    });
+  });
 });

packages/core/src/telemetry/loggers.ts

@@ -26,6 +26,7 @@ import {
   EVENT_INVALID_CHUNK,
   EVENT_CONTENT_RETRY,
   EVENT_CONTENT_RETRY_FAILURE,
+  EVENT_FILE_OPERATION,
 } from './constants.js';
 import type {
   ApiErrorEvent,
@@ -188,6 +189,34 @@ export function logFileOperation(
   ClearcutLogger.getInstance(config)?.logFileOperationEvent(event);
   if (!isTelemetrySdkInitialized()) return;
 
+  const attributes: LogAttributes = {
+    ...getCommonAttributes(config),
+    'event.name': EVENT_FILE_OPERATION,
+    'event.timestamp': new Date().toISOString(),
+    tool_name: event.tool_name,
+    operation: event.operation,
+  };
+
+  if (event.lines) {
+    attributes['lines'] = event.lines;
+  }
+  if (event.mimetype) {
+    attributes['mimetype'] = event.mimetype;
+  }
+  if (event.extension) {
+    attributes['extension'] = event.extension;
+  }
+  if (event.programming_language) {
+    attributes['programming_language'] = event.programming_language;
+  }
+
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `File operation: ${event.operation}. Lines: ${event.lines}.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+
   recordFileOperationMetric(
     config,
     event.operation,