add anthropic provider

README.md

@@ -227,6 +227,8 @@ PROVIDER_BASE_URL=                         # Custom provider base URL
 PROVIDER_API_KEY=                          # Generic provider API key
 PROVIDER_CUSTOM_HEADERS={}                 # Custom headers as JSON
 OPENAI_BASE_URL=https://api.openai.com/v1 # OpenAI base URL
+ANTHROPIC_BASE_URL=https://api.anthropic.com # Anthropic base URL
+ANTHROPIC_API_KEY=                         # Anthropic API key (if different from PROVIDER_API_KEY)
 ```
 
 **Optional - Tool Configuration:**

backend/__tests__/messages_adapter.test.js

@@ -0,0 +1,304 @@
+import { describe, test, expect } from '@jest/globals';
+import { MessagesAdapter } from '../src/lib/adapters/messagesAdapter.js';
+
+describe('MessagesAdapter', () => {
+  let adapter;
+
+  beforeEach(() => {
+    adapter = new MessagesAdapter({
+      config: {},
+      settings: {},
+      getDefaultModel: () => 'claude-3-5-sonnet-20241022',
+    });
+  });
+
+  describe('translateRequest', () => {
+    test('converts OpenAI format to Anthropic format', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [
+          { role: 'system', content: 'You are a helpful assistant.' },
+          { role: 'user', content: 'Hello!' },
+        ],
+        max_tokens: 1000,
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.model).toBe('claude-3-5-sonnet-20241022');
+      expect(result.system).toBe('You are a helpful assistant.');
+      expect(result.messages).toHaveLength(1);
+      expect(result.messages[0]).toEqual({ role: 'user', content: 'Hello!' });
+      expect(result.max_tokens).toBe(1000);
+    });
+
+    test('handles multiple system messages', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [
+          { role: 'system', content: 'First instruction.' },
+          { role: 'system', content: 'Second instruction.' },
+          { role: 'user', content: 'Hello!' },
+        ],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.system).toBe('First instruction.\n\nSecond instruction.');
+      expect(result.messages).toHaveLength(1);
+    });
+
+    test('converts tool specifications', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [{ role: 'user', content: 'Use a tool' }],
+        tools: [
+          {
+            type: 'function',
+            function: {
+              name: 'get_weather',
+              description: 'Get weather',
+              parameters: {
+                type: 'object',
+                properties: { location: { type: 'string' } },
+              },
+            },
+          },
+        ],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.tools).toHaveLength(1);
+      expect(result.tools[0]).toEqual({
+        name: 'get_weather',
+        description: 'Get weather',
+        input_schema: {
+          type: 'object',
+          properties: { location: { type: 'string' } },
+        },
+      });
+    });
+
+    test('converts assistant messages with tool calls', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [
+          { role: 'user', content: 'What is the weather?' },
+          {
+            role: 'assistant',
+            content: null,
+            tool_calls: [
+              {
+                id: 'call_123',
+                type: 'function',
+                function: {
+                  name: 'get_weather',
+                  arguments: '{"location":"San Francisco"}',
+                },
+              },
+            ],
+          },
+        ],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.messages).toHaveLength(2);
+      expect(result.messages[1].role).toBe('assistant');
+      expect(result.messages[1].content).toEqual([
+        {
+          type: 'tool_use',
+          id: 'call_123',
+          name: 'get_weather',
+          input: { location: 'San Francisco' },
+        },
+      ]);
+    });
+
+    test('converts tool results from OpenAI format', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [
+          { role: 'user', content: 'What is the weather?' },
+          {
+            role: 'tool',
+            tool_call_id: 'call_123',
+            content: 'Sunny, 72°F',
+          },
+        ],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.messages).toHaveLength(2);
+      expect(result.messages[1].role).toBe('user');
+      expect(result.messages[1].content).toEqual([
+        {
+          type: 'tool_result',
+          tool_use_id: 'call_123',
+          content: 'Sunny, 72°F',
+        },
+      ]);
+    });
+
+    test('sets default max_tokens if not provided', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [{ role: 'user', content: 'Hello!' }],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.max_tokens).toBe(4096);
+    });
+
+    test('uses default model if not specified', async () => {
+      const internalRequest = {
+        messages: [{ role: 'user', content: 'Hello!' }],
+      };
+
+      const result = await adapter.translateRequest(internalRequest);
+
+      expect(result.model).toBe('claude-3-5-sonnet-20241022');
+    });
+
+    test('throws error if no model and no default', async () => {
+      const adapterNoDefault = new MessagesAdapter({
+        config: {},
+        settings: {},
+        getDefaultModel: () => undefined,
+      });
+
+      const internalRequest = {
+        messages: [{ role: 'user', content: 'Hello!' }],
+      };
+
+      await expect(adapterNoDefault.translateRequest(internalRequest)).rejects.toThrow(
+        'Anthropic provider requires a model'
+      );
+    });
+
+    test('throws error if no non-system messages', async () => {
+      const internalRequest = {
+        model: 'claude-3-5-sonnet-20241022',
+        messages: [{ role: 'system', content: 'System only' }],
+      };
+
+      await expect(adapter.translateRequest(internalRequest)).rejects.toThrow(
+        'Anthropic provider requires at least one non-system message'
+      );
+    });
+  });
+
+  describe('translateResponse', () => {
+    test('converts Anthropic response to OpenAI format', async () => {
+      const anthropicResponse = {
+        id: 'msg_123',
+        type: 'message',
+        role: 'assistant',
+        model: 'claude-3-5-sonnet-20241022',
+        content: [{ type: 'text', text: 'Hello! How can I help?' }],
+        stop_reason: 'end_turn',
+        usage: { input_tokens: 10, output_tokens: 20 },
+      };
+
+      const result = await adapter.translateResponse(anthropicResponse);
+
+      expect(result.id).toBe('msg_123');
+      expect(result.object).toBe('chat.completion');
+      expect(result.model).toBe('claude-3-5-sonnet-20241022');
+      expect(result.choices).toHaveLength(1);
+      expect(result.choices[0].message.role).toBe('assistant');
+      expect(result.choices[0].message.content).toBe('Hello! How can I help?');
+      expect(result.choices[0].finish_reason).toBe('stop');
+      expect(result.usage).toEqual({
+        prompt_tokens: 10,
+        completion_tokens: 20,
+        total_tokens: 30,
+      });
+    });
+
+    test('converts tool use in response', async () => {
+      const anthropicResponse = {
+        id: 'msg_123',
+        type: 'message',
+        role: 'assistant',
+        model: 'claude-3-5-sonnet-20241022',
+        content: [
+          { type: 'text', text: 'Let me check that.' },
+          {
+            type: 'tool_use',
+            id: 'tool_123',
+            name: 'get_weather',
+            input: { location: 'San Francisco' },
+          },
+        ],
+        stop_reason: 'tool_use',
+        usage: { input_tokens: 10, output_tokens: 20 },
+      };
+
+      const result = await adapter.translateResponse(anthropicResponse);
+
+      expect(result.choices[0].message.content).toBe('Let me check that.');
+      expect(result.choices[0].message.tool_calls).toHaveLength(1);
+      expect(result.choices[0].message.tool_calls[0]).toEqual({
+        id: 'tool_123',
+        type: 'function',
+        function: {
+          name: 'get_weather',
+          arguments: '{"location":"San Francisco"}',
+        },
+        index: 1,
+      });
+    });
+  });
+
+  describe('translateStreamChunk', () => {
+    test('converts message_start event', () => {
+      const event = {
+        type: 'message_start',
+        message: {
+          id: 'msg_123',
+          model: 'claude-3-5-sonnet-20241022',
+        },
+      };
+
+      const result = adapter.translateStreamChunk(event);
+
+      expect(result.id).toBe('msg_123');
+      expect(result.object).toBe('chat.completion.chunk');
+      expect(result.model).toBe('claude-3-5-sonnet-20241022');
+      expect(result.choices[0].delta.role).toBe('assistant');
+      expect(result.choices[0].delta.content).toBe('');
+    });
+
+    test('converts content_block_delta with text', () => {
+      const event = {
+        type: 'content_block_delta',
+        index: 0,
+        delta: { type: 'text_delta', text: 'Hello' },
+      };
+
+      const result = adapter.translateStreamChunk(event);
+
+      expect(result.choices[0].delta.content).toBe('Hello');
+    });
+
+    test('converts message_stop event', () => {
+      const event = { type: 'message_stop' };
+
+      const result = adapter.translateStreamChunk(event);
+
+      expect(result).toBe('[DONE]');
+    });
+
+    test('returns null for ping events', () => {
+      const event = { type: 'ping' };
+
+      const result = adapter.translateStreamChunk(event);
+
+      expect(result).toBeNull();
+    });
+  });
+});