Phase 7: Directory restructuring (messaging/ and tests/)

- Create messaging/platforms/ (base, discord, telegram, factory)
- Create messaging/rendering/ (discord_markdown, telegram_markdown)
- Create messaging/trees/ (data, repository, processor, queue_manager)
- Organize tests/ into api/, providers/, messaging/, cli/, config/
- Add backward-compatible re-exports at old locations
- Update handler.py and test_messaging_factory.py imports
- Fix Telegram type hints for TELEGRAM_AVAILABLE=False case
- Fix Python 3 except syntax in discord_markdown

Co-authored-by: Ali Khokhar <alishahryar2@gmail.com>

tests/api/test_api.py

@@ -0,0 +1,178 @@
+from fastapi.testclient import TestClient
+from api.app import app
+from api.dependencies import get_provider
+from unittest.mock import MagicMock
+from providers.nvidia_nim import NvidiaNimProvider
+
+# Mock provider
+mock_provider = MagicMock(spec=NvidiaNimProvider)
+
+# Track stream_response calls for test_model_mapping
+_stream_response_calls = []
+
+
+async def _mock_stream_response(*args, **kwargs):
+    """Minimal async generator for streaming tests."""
+    _stream_response_calls.append((args, kwargs))
+    yield "event: message_start\ndata: {}\n\n"
+    yield "[DONE]\n\n"
+
+
+mock_provider.stream_response = _mock_stream_response
+
+
+def override_get_provider():
+    return mock_provider
+
+
+app.dependency_overrides[get_provider] = override_get_provider
+client = TestClient(app)
+
+
+def test_root():
+    response = client.get("/")
+    assert response.status_code == 200
+    assert response.json()["status"] == "ok"
+
+
+def test_health():
+    response = client.get("/health")
+    assert response.status_code == 200
+    assert response.json()["status"] == "healthy"
+
+
+def test_create_message_stream():
+    """Create message returns streaming response."""
+    payload = {
+        "model": "claude-3-sonnet",
+        "messages": [{"role": "user", "content": "Hi"}],
+        "max_tokens": 100,
+        "stream": True,
+    }
+    response = client.post("/v1/messages", json=payload)
+    assert response.status_code == 200
+    assert "text/event-stream" in response.headers.get("content-type", "")
+    content = b"".join(response.iter_bytes())
+    assert b"message_start" in content or b"event:" in content
+
+
+def test_model_mapping():
+    # Test Haiku mapping
+    _stream_response_calls.clear()
+    payload_haiku = {
+        "model": "claude-3-haiku-20240307",
+        "messages": [{"role": "user", "content": "Hi"}],
+        "max_tokens": 100,
+        "stream": True,
+    }
+    client.post("/v1/messages", json=payload_haiku)
+    assert len(_stream_response_calls) == 1
+    args = _stream_response_calls[0][0]
+    assert args[0].model != "claude-3-haiku-20240307"
+    assert args[0].original_model == "claude-3-haiku-20240307"
+
+
+def test_error_fallbacks():
+    from providers.exceptions import (
+        AuthenticationError,
+        RateLimitError,
+        OverloadedError,
+    )
+
+    base_payload = {"model": "test", "messages": [], "max_tokens": 10, "stream": True}
+
+    def _raise_auth(*args, **kwargs):
+        raise AuthenticationError("Invalid Key")
+
+    def _raise_rate_limit(*args, **kwargs):
+        raise RateLimitError("Too Many Requests")
+
+    def _raise_overloaded(*args, **kwargs):
+        raise OverloadedError("Server Overloaded")
+
+    # 1. Authentication Error (401)
+    mock_provider.stream_response = _raise_auth
+    response = client.post("/v1/messages", json=base_payload)
+    assert response.status_code == 401
+    assert response.json()["error"]["type"] == "authentication_error"
+
+    # 2. Rate Limit (429)
+    mock_provider.stream_response = _raise_rate_limit
+    response = client.post("/v1/messages", json=base_payload)
+    assert response.status_code == 429
+    assert response.json()["error"]["type"] == "rate_limit_error"
+
+    # 3. Overloaded (529)
+    mock_provider.stream_response = _raise_overloaded
+    response = client.post("/v1/messages", json=base_payload)
+    assert response.status_code == 529
+    assert response.json()["error"]["type"] == "overloaded_error"
+
+    # Reset for subsequent tests
+    mock_provider.stream_response = _mock_stream_response
+
+
+def test_generic_exception_returns_500():
+    """Non-ProviderError exceptions are caught and returned as HTTPException(500)."""
+
+    def _raise_runtime(*args, **kwargs):
+        raise RuntimeError("unexpected crash")
+
+    mock_provider.stream_response = _raise_runtime
+    response = client.post(
+        "/v1/messages",
+        json={
+            "model": "test",
+            "messages": [{"role": "user", "content": "Hi"}],
+            "max_tokens": 10,
+            "stream": True,
+        },
+    )
+    assert response.status_code == 500
+    mock_provider.stream_response = _mock_stream_response
+
+
+def test_generic_exception_with_status_code():
+    """Generic exception with status_code attribute uses that status (getattr fallback)."""
+
+    class ExceptionWithStatus(RuntimeError):
+        def __init__(self, msg: str, status_code: int = 500):
+            super().__init__(msg)
+            self.status_code = status_code
+
+    def _raise_with_status(*args, **kwargs):
+        raise ExceptionWithStatus("bad gateway", 502)
+
+    mock_provider.stream_response = _raise_with_status
+    response = client.post(
+        "/v1/messages",
+        json={
+            "model": "test",
+            "messages": [{"role": "user", "content": "Hi"}],
+            "max_tokens": 10,
+            "stream": True,
+        },
+    )
+    assert response.status_code == 502
+    mock_provider.stream_response = _mock_stream_response
+
+
+def test_count_tokens_endpoint():
+    """count_tokens endpoint returns token count."""
+    response = client.post(
+        "/v1/messages/count_tokens",
+        json={"model": "test", "messages": [{"role": "user", "content": "Hello"}]},
+    )
+    assert response.status_code == 200
+    assert "input_tokens" in response.json()
+
+
+def test_stop_endpoint_no_handler_no_cli_503():
+    """POST /stop without handler or cli_manager returns 503."""
+    # Ensure no handler or cli_manager on app state
+    if hasattr(app.state, "message_handler"):
+        delattr(app.state, "message_handler")
+    if hasattr(app.state, "cli_manager"):
+        delattr(app.state, "cli_manager")
+    response = client.post("/stop")
+    assert response.status_code == 503