Files
AutoGPT/autogpt_platform/backend/backend/copilot/model_test.py
Otto e40c8c70ce fix(copilot): collision detection, session locking, and sync for concurrent message saves (#12177)
Requested by @majdyz

Concurrent writers (incremental streaming saves from PR #12173 and
long-running tool callbacks) can race to persist messages with the same
`(sessionId, sequence)` pair, causing unique constraint violations on
`ChatMessage`.

**Root cause:** The streaming loop tracks `saved_msg_count` in-memory,
but the long-running tool callback (`_build_long_running_callback`) also
appends messages and calls `upsert_chat_session` independently — without
coordinating sequence numbers. When the streaming loop does its next
incremental save with the stale `saved_msg_count`, it tries to insert at
a sequence that already exists.

**Fix:** Multi-layered defense-in-depth approach:

1. **Collision detection with retry** (db.py): `add_chat_messages_batch`
uses `create_many()` in a transaction. On `UniqueViolationError`,
queries `MAX(sequence)+1` from DB and retries with the correct offset
(max 5 attempts).

2. **Robust sequence tracking** (db.py): `get_next_sequence()` uses
indexed `find_first` with `order={"sequence": "desc"}` for O(1) MAX
lookup, immune to deleted messages.

3. **Session-based counter** (model.py): Added `saved_message_count`
field to `ChatSession`. `upsert_chat_session` returns the session with
updated count, eliminating tuple returns throughout the codebase.

4. **MessageCounter dataclass** (sdk/service.py): Replaced list[int]
mutable reference pattern with a clean `MessageCounter` dataclass for
shared state between streaming loop and long-running callbacks.

5. **Session locking** (sdk/service.py): Prevent concurrent streams on
the same session using Redis `SET NX EX` distributed locks with TTL
refresh on heartbeats (config.stream_ttl = 3600s).

6. **Atomic operations** (db.py): Single timestamp for all messages and
session update in batch operations for consistency. Parallel queries
with `asyncio.gather` for lower latency.

7. **Config-based TTL** (sdk/service.py, config.py): Consolidated all
TTL constants to use `config.stream_ttl` (3600s) with lock refresh on
heartbeats.

### Key implementation details

- **create_many**: Uses `sessionId` directly (not nested
`Session.connect`) as `create_many` doesn't support nested creates
- **Type narrowing**: Added explicit `assert session is not None`
statements for pyright type checking in async contexts
- **Parallel operations**: Use `asyncio.gather` for independent DB
operations (create_many + session update)
- **Single timestamp**: All messages in a batch share the same
`createdAt` timestamp for atomicity

### Changes
- `backend/copilot/db.py`: Collision detection with `create_many` +
retry, indexed sequence lookup, single timestamp, parallel queries
- `backend/copilot/model.py`: Added `saved_message_count` field,
simplified return types
- `backend/copilot/sdk/service.py`: MessageCounter dataclass, session
locking with refresh, config-based TTL, type narrowing
- `backend/copilot/service.py`: Updated all callers to handle new return
types
- `backend/copilot/config.py`: Increased long_running_operation_ttl to
3600s with clarified docstring
- `backend/copilot/*_test.py`: Tests updated for new signatures

---------

Co-authored-by: Zamil Majdy <zamil.majdy@agpt.co>
2026-02-20 15:05:03 +00:00

427 lines
15 KiB
Python

from typing import cast
import pytest
from openai.types.chat import (
ChatCompletionAssistantMessageParam,
ChatCompletionMessageParam,
ChatCompletionToolMessageParam,
ChatCompletionUserMessageParam,
)
from openai.types.chat.chat_completion_message_tool_call_param import (
ChatCompletionMessageToolCallParam,
Function,
)
from .model import (
ChatMessage,
ChatSession,
Usage,
get_chat_session,
upsert_chat_session,
)
messages = [
ChatMessage(content="Hello, how are you?", role="user"),
ChatMessage(
content="I'm fine, thank you!",
role="assistant",
tool_calls=[
{
"id": "t123",
"type": "function",
"function": {
"name": "get_weather",
"arguments": '{"city": "New York"}',
},
}
],
),
ChatMessage(
content="I'm using the tool to get the weather",
role="tool",
tool_call_id="t123",
),
]
@pytest.mark.asyncio(loop_scope="session")
async def test_chatsession_serialization_deserialization():
s = ChatSession.new(user_id="abc123")
s.messages = messages
s.usage = [Usage(prompt_tokens=100, completion_tokens=200, total_tokens=300)]
serialized = s.model_dump_json()
s2 = ChatSession.model_validate_json(serialized)
assert s2.model_dump() == s.model_dump()
@pytest.mark.asyncio(loop_scope="session")
async def test_chatsession_redis_storage(setup_test_user, test_user_id):
s = ChatSession.new(user_id=test_user_id)
s.messages = messages
s = await upsert_chat_session(s)
s2 = await get_chat_session(
session_id=s.session_id,
user_id=s.user_id,
)
assert s2 == s
@pytest.mark.asyncio(loop_scope="session")
async def test_chatsession_redis_storage_user_id_mismatch(
setup_test_user, test_user_id
):
s = ChatSession.new(user_id=test_user_id)
s.messages = messages
s = await upsert_chat_session(s)
s2 = await get_chat_session(s.session_id, "different_user_id")
assert s2 is None
@pytest.mark.asyncio(loop_scope="session")
async def test_chatsession_db_storage(setup_test_user, test_user_id):
"""Test that messages are correctly saved to and loaded from DB (not cache)."""
from backend.data.redis_client import get_redis_async
# Create session with messages including assistant message
s = ChatSession.new(user_id=test_user_id)
s.messages = messages # Contains user, assistant, and tool messages
assert s.session_id is not None, "Session id is not set"
# Upsert to save to both cache and DB
s = await upsert_chat_session(s)
# Clear the Redis cache to force DB load
redis_key = f"chat:session:{s.session_id}"
async_redis = await get_redis_async()
await async_redis.delete(redis_key)
# Load from DB (cache was cleared)
s2 = await get_chat_session(
session_id=s.session_id,
user_id=s.user_id,
)
assert s2 is not None, "Session not found after loading from DB"
assert len(s2.messages) == len(
s.messages
), f"Message count mismatch: expected {len(s.messages)}, got {len(s2.messages)}"
# Verify all roles are present
roles = [m.role for m in s2.messages]
assert "user" in roles, f"User message missing. Roles found: {roles}"
assert "assistant" in roles, f"Assistant message missing. Roles found: {roles}"
assert "tool" in roles, f"Tool message missing. Roles found: {roles}"
# Verify message content
for orig, loaded in zip(s.messages, s2.messages):
assert orig.role == loaded.role, f"Role mismatch: {orig.role} != {loaded.role}"
assert (
orig.content == loaded.content
), f"Content mismatch for {orig.role}: {orig.content} != {loaded.content}"
if orig.tool_calls:
assert (
loaded.tool_calls is not None
), f"Tool calls missing for {orig.role} message"
assert len(orig.tool_calls) == len(loaded.tool_calls)
# --------------------------------------------------------------------------- #
# _merge_consecutive_assistant_messages #
# --------------------------------------------------------------------------- #
_tc = ChatCompletionMessageToolCallParam(
id="tc1", type="function", function=Function(name="do_stuff", arguments="{}")
)
_tc2 = ChatCompletionMessageToolCallParam(
id="tc2", type="function", function=Function(name="other", arguments="{}")
)
def test_merge_noop_when_no_consecutive_assistants():
"""Messages without consecutive assistants are returned unchanged."""
msgs = [
ChatCompletionUserMessageParam(role="user", content="hi"),
ChatCompletionAssistantMessageParam(role="assistant", content="hello"),
ChatCompletionUserMessageParam(role="user", content="bye"),
]
merged = ChatSession._merge_consecutive_assistant_messages(msgs)
assert len(merged) == 3
assert [m["role"] for m in merged] == ["user", "assistant", "user"]
def test_merge_splits_text_and_tool_calls():
"""The exact bug scenario: text-only assistant followed by tool_calls-only assistant."""
msgs = [
ChatCompletionUserMessageParam(role="user", content="build agent"),
ChatCompletionAssistantMessageParam(
role="assistant", content="Let me build that"
),
ChatCompletionAssistantMessageParam(
role="assistant", content="", tool_calls=[_tc]
),
ChatCompletionToolMessageParam(role="tool", content="ok", tool_call_id="tc1"),
]
merged = ChatSession._merge_consecutive_assistant_messages(msgs)
assert len(merged) == 3
assert merged[0]["role"] == "user"
assert merged[2]["role"] == "tool"
a = cast(ChatCompletionAssistantMessageParam, merged[1])
assert a["role"] == "assistant"
assert a.get("content") == "Let me build that"
assert a.get("tool_calls") == [_tc]
def test_merge_combines_tool_calls_from_both():
"""Both consecutive assistants have tool_calls — they get merged."""
msgs: list[ChatCompletionAssistantMessageParam] = [
ChatCompletionAssistantMessageParam(
role="assistant", content="text", tool_calls=[_tc]
),
ChatCompletionAssistantMessageParam(
role="assistant", content="", tool_calls=[_tc2]
),
]
merged = ChatSession._merge_consecutive_assistant_messages(msgs) # type: ignore[arg-type]
assert len(merged) == 1
a = cast(ChatCompletionAssistantMessageParam, merged[0])
assert a.get("tool_calls") == [_tc, _tc2]
assert a.get("content") == "text"
def test_merge_three_consecutive_assistants():
"""Three consecutive assistants collapse into one."""
msgs: list[ChatCompletionAssistantMessageParam] = [
ChatCompletionAssistantMessageParam(role="assistant", content="a"),
ChatCompletionAssistantMessageParam(role="assistant", content="b"),
ChatCompletionAssistantMessageParam(
role="assistant", content="", tool_calls=[_tc]
),
]
merged = ChatSession._merge_consecutive_assistant_messages(msgs) # type: ignore[arg-type]
assert len(merged) == 1
a = cast(ChatCompletionAssistantMessageParam, merged[0])
assert a.get("content") == "a\nb"
assert a.get("tool_calls") == [_tc]
def test_merge_empty_and_single_message():
"""Edge cases: empty list and single message."""
assert ChatSession._merge_consecutive_assistant_messages([]) == []
single: list[ChatCompletionMessageParam] = [
ChatCompletionUserMessageParam(role="user", content="hi")
]
assert ChatSession._merge_consecutive_assistant_messages(single) == single
# --------------------------------------------------------------------------- #
# add_tool_call_to_current_turn #
# --------------------------------------------------------------------------- #
_raw_tc = {
"id": "tc1",
"type": "function",
"function": {"name": "f", "arguments": "{}"},
}
_raw_tc2 = {
"id": "tc2",
"type": "function",
"function": {"name": "g", "arguments": "{}"},
}
def test_add_tool_call_appends_to_existing_assistant():
"""When the last assistant is from the current turn, tool_call is added to it."""
session = ChatSession.new(user_id="u")
session.messages = [
ChatMessage(role="user", content="hi"),
ChatMessage(role="assistant", content="working on it"),
]
session.add_tool_call_to_current_turn(_raw_tc)
assert len(session.messages) == 2 # no new message created
assert session.messages[1].tool_calls == [_raw_tc]
def test_add_tool_call_creates_assistant_when_none_exists():
"""When there's no current-turn assistant, a new one is created."""
session = ChatSession.new(user_id="u")
session.messages = [
ChatMessage(role="user", content="hi"),
]
session.add_tool_call_to_current_turn(_raw_tc)
assert len(session.messages) == 2
assert session.messages[1].role == "assistant"
assert session.messages[1].tool_calls == [_raw_tc]
def test_add_tool_call_does_not_cross_user_boundary():
"""A user message acts as a boundary — previous assistant is not modified."""
session = ChatSession.new(user_id="u")
session.messages = [
ChatMessage(role="assistant", content="old turn"),
ChatMessage(role="user", content="new message"),
]
session.add_tool_call_to_current_turn(_raw_tc)
assert len(session.messages) == 3 # new assistant was created
assert session.messages[0].tool_calls is None # old assistant untouched
assert session.messages[2].role == "assistant"
assert session.messages[2].tool_calls == [_raw_tc]
def test_add_tool_call_multiple_times():
"""Multiple long-running tool calls accumulate on the same assistant."""
session = ChatSession.new(user_id="u")
session.messages = [
ChatMessage(role="user", content="hi"),
ChatMessage(role="assistant", content="doing stuff"),
]
session.add_tool_call_to_current_turn(_raw_tc)
# Simulate a pending tool result in between (like _yield_tool_call does)
session.messages.append(
ChatMessage(role="tool", content="pending", tool_call_id="tc1")
)
session.add_tool_call_to_current_turn(_raw_tc2)
assert len(session.messages) == 3 # user, assistant, tool — no extra assistant
assert session.messages[1].tool_calls == [_raw_tc, _raw_tc2]
def test_to_openai_messages_merges_split_assistants():
"""End-to-end: session with split assistants produces valid OpenAI messages."""
session = ChatSession.new(user_id="u")
session.messages = [
ChatMessage(role="user", content="build agent"),
ChatMessage(role="assistant", content="Let me build that"),
ChatMessage(
role="assistant",
content="",
tool_calls=[
{
"id": "tc1",
"type": "function",
"function": {"name": "create_agent", "arguments": "{}"},
}
],
),
ChatMessage(role="tool", content="done", tool_call_id="tc1"),
ChatMessage(role="assistant", content="Saved!"),
ChatMessage(role="user", content="show me an example run"),
]
openai_msgs = session.to_openai_messages()
# The two consecutive assistants at index 1,2 should be merged
roles = [m["role"] for m in openai_msgs]
assert roles == ["user", "assistant", "tool", "assistant", "user"]
# The merged assistant should have both content and tool_calls
merged = cast(ChatCompletionAssistantMessageParam, openai_msgs[1])
assert merged.get("content") == "Let me build that"
tc_list = merged.get("tool_calls")
assert tc_list is not None and len(list(tc_list)) == 1
assert list(tc_list)[0]["id"] == "tc1"
# --------------------------------------------------------------------------- #
# Concurrent save collision detection #
# --------------------------------------------------------------------------- #
@pytest.mark.asyncio(loop_scope="session")
async def test_concurrent_saves_collision_detection(setup_test_user, test_user_id):
"""Test that concurrent saves from streaming loop and callback handle collisions correctly.
Simulates the race condition where:
1. Streaming loop starts with saved_msg_count=5
2. Long-running callback appends message #5 and saves
3. Streaming loop tries to save with stale count=5
The collision detection should handle this gracefully.
"""
import asyncio
# Create a session with initial messages
session = ChatSession.new(user_id=test_user_id)
for i in range(3):
session.messages.append(
ChatMessage(
role="user" if i % 2 == 0 else "assistant", content=f"Message {i}"
)
)
# Save initial messages
session = await upsert_chat_session(session)
# Simulate streaming loop and callback saving concurrently
async def streaming_loop_save():
"""Simulates streaming loop saving messages."""
# Add 2 messages
session.messages.append(ChatMessage(role="user", content="Streaming message 1"))
session.messages.append(
ChatMessage(role="assistant", content="Streaming message 2")
)
# Wait a bit to let callback potentially save first
await asyncio.sleep(0.01)
# Save (will query DB for existing count)
return await upsert_chat_session(session)
async def callback_save():
"""Simulates long-running callback saving a message."""
# Add 1 message
session.messages.append(
ChatMessage(role="tool", content="Callback result", tool_call_id="tc1")
)
# Save immediately (will query DB for existing count)
return await upsert_chat_session(session)
# Run both saves concurrently - one will hit collision detection
results = await asyncio.gather(streaming_loop_save(), callback_save())
# Both should succeed
assert all(r is not None for r in results)
# Reload session from DB to verify
from backend.data.redis_client import get_redis_async
redis_key = f"chat:session:{session.session_id}"
async_redis = await get_redis_async()
await async_redis.delete(redis_key) # Clear cache to force DB load
loaded_session = await get_chat_session(session.session_id, test_user_id)
assert loaded_session is not None
# Should have all 6 messages (3 initial + 2 streaming + 1 callback)
assert len(loaded_session.messages) == 6
# Verify no duplicate sequences
sequences = []
for i, msg in enumerate(loaded_session.messages):
# Messages should have sequential sequence numbers starting from 0
sequences.append(i)
# All sequences should be unique and sequential
assert sequences == list(range(6))
# Verify message content is preserved
contents = [m.content for m in loaded_session.messages]
assert "Message 0" in contents
assert "Message 1" in contents
assert "Message 2" in contents
assert "Streaming message 1" in contents
assert "Streaming message 2" in contents
assert "Callback result" in contents