1 files changed, 119 insertions, 0 deletions
diff --git a/packages/core/src/telemetry/loggers.test.ts b/packages/core/src/telemetry/loggers.test.ts
new file mode 100644
index 00000000..3493dc49
--- /dev/null
+++ b/packages/core/src/telemetry/loggers.test.ts
@@ -0,0 +1,119 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { logs } from '@opentelemetry/api-logs';
+import { SemanticAttributes } from '@opentelemetry/semantic-conventions';
+import { Config } from '../config/config.js';
+import { EVENT_API_RESPONSE } from './constants.js';
+import { logApiResponse } from './loggers.js';
+import * as metrics from './metrics.js';
+import * as sdk from './sdk.js';
+import { vi, describe, beforeEach, it, expect } from 'vitest';
+
+describe('logApiResponse', () => {
+  const mockConfig = {
+    getSessionId: () => 'test-session-id',
+  } as Config;
+
+  const mockLogger = {
+    emit: vi.fn(),
+  };
+
+  const mockMetrics = {
+    recordApiResponseMetrics: vi.fn(),
+    recordTokenUsageMetrics: vi.fn(),
+  };
+
+  beforeEach(() => {
+    vi.spyOn(sdk, 'isTelemetrySdkInitialized').mockReturnValue(true);
+    vi.spyOn(logs, 'getLogger').mockReturnValue(mockLogger);
+    vi.spyOn(metrics, 'recordApiResponseMetrics').mockImplementation(
+      mockMetrics.recordApiResponseMetrics,
+    );
+    vi.spyOn(metrics, 'recordTokenUsageMetrics').mockImplementation(
+      mockMetrics.recordTokenUsageMetrics,
+    );
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date('2025-01-01T00:00:00.000Z'));
+  });
+
+  it('should log an API response with all fields', () => {
+    const event = {
+      model: 'test-model',
+      status_code: 200,
+      duration_ms: 100,
+      attempt: 1,
+      output_token_count: 50,
+      cached_content_token_count: 10,
+      thoughts_token_count: 5,
+      tool_token_count: 2,
+      response_text: 'test-response',
+    };
+
+    logApiResponse(mockConfig, event);
+
+    expect(mockLogger.emit).toHaveBeenCalledWith({
+      body: 'API response from test-model. Status: 200. Duration: 100ms.',
+      attributes: {
+        'session.id': 'test-session-id',
+        'event.name': EVENT_API_RESPONSE,
+        'event.timestamp': '2025-01-01T00:00:00.000Z',
+        [SemanticAttributes.HTTP_STATUS_CODE]: 200,
+        model: 'test-model',
+        status_code: 200,
+        duration_ms: 100,
+        attempt: 1,
+        output_token_count: 50,
+        cached_content_token_count: 10,
+        thoughts_token_count: 5,
+        tool_token_count: 2,
+        response_text: 'test-response',
+      },
+    });
+
+    expect(mockMetrics.recordApiResponseMetrics).toHaveBeenCalledWith(
+      mockConfig,
+      'test-model',
+      100,
+      200,
+      undefined,
+    );
+
+    expect(mockMetrics.recordTokenUsageMetrics).toHaveBeenCalledWith(
+      mockConfig,
+      'test-model',
+      50,
+      'output',
+    );
+  });
+
+  it('should log an API response with an error', () => {
+    const event = {
+      model: 'test-model',
+      duration_ms: 100,
+      attempt: 1,
+      error: 'test-error',
+      output_token_count: 50,
+      cached_content_token_count: 10,
+      thoughts_token_count: 5,
+      tool_token_count: 2,
+      response_text: 'test-response',
+    };
+
+    logApiResponse(mockConfig, event);
+
+    expect(mockLogger.emit).toHaveBeenCalledWith({
+      body: 'API response from test-model. Status: N/A. Duration: 100ms.',
+      attributes: {
+        'session.id': 'test-session-id',
+        ...event,
+        'event.name': EVENT_API_RESPONSE,
+        'event.timestamp': '2025-01-01T00:00:00.000Z',
+        'error.message': 'test-error',
+      },
+    });
+  });
+});