Consolidating to asyncio.Lock over threading.Lock

[rodrigobr-msft]

This pull request updates the in-memory storage and transcript store implementations to use asyncio.Lock and async with for concurrency control instead of the standard threading Lock. This change ensures that locking is compatible with asynchronous code, preventing potential deadlocks or blocking in async environments.

Concurrency model update:

• Replaced threading.Lock with asyncio.Lock in both memory_storage.py and transcript_memory_store.py to ensure proper synchronization in async contexts. [1] [2]

• Updated all critical sections in MemoryStorage methods (read, write, delete) to use async with self._lock: instead of with self._lock:. [1] [2] [3]

• Updated all critical sections in TranscriptMemoryStore methods (log_activity, get_transcript_activities, delete_transcript, list_transcripts) to use async with self.lock: instead of with self.lock:. [1] [2] [3] [4]

[Copilot]

Pull request overview

This PR updates the in-memory storage implementations to use asyncio.Lock/async with instead of threading.Lock/with, aligning concurrency control with the project’s async execution model and avoiding blocking the event loop.

Changes:

• Switched MemoryStorage to use asyncio.Lock and async with for read/write/delete critical sections.
• Switched TranscriptMemoryStore to use asyncio.Lock and async with for transcript mutation and queries.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/memory_storage.py	Replaces sync locking with asyncio.Lock and async context management around in-memory state access.
libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/transcript_memory_store.py	Replaces sync locking with asyncio.Lock and async context management around transcript operations.

Comments suppressed due to low confidence (1)

libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/memory_storage.py:33

• Inside MemoryStorage.read(), target_cls is validated as non-None before the lock, so the later if not target_cls: branch is unreachable. This dead branch also forces result to be typed as dict[str, StoreItem] even though the method returns dict[str, StoreItemT]. Simplify the branch and align the type annotation.

        async with self._lock:
            for key in keys:
                if key == "":
                    raise ValueError("MemoryStorage.read(): key cannot be empty")
                if key in self._memory:

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (3)

libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/memory_storage.py:33

• In an async context, it’s better to validate keys before awaiting on the lock. As written, an invalid key can still acquire the lock first, unnecessarily blocking other coroutines.

        async with self._lock:
            for key in keys:
                if key == "":
                    raise ValueError("MemoryStorage.read(): key cannot be empty")
                if key in self._memory:

libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/memory_storage.py:55

• In an async context, validate inputs before awaiting on the lock. This avoids acquiring the lock (and potentially blocking other tasks) when the request is invalid.

        async with self._lock:
            for key in changes:
                if key == "":
                    raise ValueError("MemoryStorage.write(): key cannot be empty")
                self._memory[key] = changes[key].store_item_to_json()

libraries/microsoft-agents-hosting-core/microsoft_agents/hosting/core/storage/memory_storage.py:65

• In an async context, validate inputs before awaiting on the lock. This prevents invalid input from taking the lock and briefly blocking other coroutines.

        async with self._lock:
            for key in keys:
                if key == "":
                    raise ValueError("MemoryStorage.delete(): key cannot be empty")
                if key in self._memory:

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.