feat: Added a sync toolbox client

packages/toolbox-core/src/toolbox_core/__init__.py

@@ -13,5 +13,6 @@
 # limitations under the License.
 
 from .client import ToolboxClient
+from .sync_client import ToolboxSyncClient
 
-__all__ = ["ToolboxClient"]
+__all__ = ["ToolboxClient", "ToolboxSyncClient"]

packages/toolbox-core/src/toolbox_core/sync_client.py

@@ -0,0 +1,171 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import asyncio
+from threading import Thread
+from typing import Any, Awaitable, Callable, Mapping, Optional, TypeVar, Union
+
+from aiohttp import ClientSession
+
+from .client import ToolboxClient
+from .sync_tool import ToolboxSyncTool
+
+T = TypeVar("T")
+
+
+class ToolboxSyncClient:
+    """
+    A synchronous client for interacting with a Toolbox service.
+
+    Provides methods to discover and load tools defined by a remote Toolbox
+    service endpoint, returning synchronous tool wrappers (`SyncToolboxTool`).
+    It manages an underlying asynchronous `ToolboxClient`.
+    """
+
+    __session: Optional[ClientSession] = None
+    __loop: Optional[asyncio.AbstractEventLoop] = None
+    __thread: Optional[Thread] = None
+
+    def __init__(
+        self,
+        url: str,
+    ):
+        """
+        Initializes the SyncToolboxClient.
+
+        Args:
+            url: The base URL for the Toolbox service API (e.g., "http://localhost:8000").
+        """
+        # Running a loop in a background thread allows us to support async
+        # methods from non-async environments.
+        if ToolboxSyncClient.__loop is None:
+            loop = asyncio.new_event_loop()
+            thread = Thread(target=loop.run_forever, daemon=True)
+            thread.start()
+            ToolboxSyncClient.__thread = thread
+            ToolboxSyncClient.__loop = loop
+
+        async def __start_session() -> None:
+            # Use a default session if none is provided. This leverages connection
+            # pooling for better performance by reusing a single session throughout
+            # the application's lifetime.
+            if ToolboxSyncClient.__session is None:
+                ToolboxSyncClient.__session = ClientSession()
+
+        coro = __start_session()
+
+        asyncio.run_coroutine_threadsafe(coro, ToolboxSyncClient.__loop).result()
+
+        if not ToolboxSyncClient.__session:
+            raise ValueError("Session cannot be None.")
+        self.__async_client = ToolboxClient(url, ToolboxSyncClient.__session)
+
+    def __run_as_sync(self, coro: Awaitable[T]) -> T:
+        """Run an async coroutine synchronously"""
+        if not self.__loop:
+            raise Exception(
+                "Cannot call synchronous methods before the background loop is initialized."
+            )
+        return asyncio.run_coroutine_threadsafe(coro, self.__loop).result()
+
+    async def __run_as_async(self, coro: Awaitable[T]) -> T:
+        """Run an async coroutine asynchronously"""
+
+        # If a loop has not been provided, attempt to run in current thread.
+        if not self.__loop:
+            return await coro
+
+        # Otherwise, run in the background thread.
+        return await asyncio.wrap_future(
+            asyncio.run_coroutine_threadsafe(coro, self.__loop)
+        )
+
+    def load_tool(
+        self,
+        tool_name: str,
+        auth_token_getters: dict[str, Callable[[], str]] = {},
+        bound_params: Mapping[str, Union[Callable[[], Any], Any]] = {},
+    ) -> ToolboxSyncTool:
+        """
+        Synchronously loads a tool from the server.
+
+        Retrieves the schema for the specified tool and returns a callable,
+        synchronous object (`SyncToolboxTool`) that can be used to invoke the
+        tool remotely.
+
+        Args:
+            tool_name: Name of the tool to load.
+            auth_token_getters: A mapping of authentication service names to
+                callables that return the corresponding authentication token.
+            bound_params: A mapping of parameter names to bind to specific values or
+                callables that are called to produce values as needed.
+
+        Returns:
+            ToolboxSyncTool: A synchronous callable object representing the loaded tool.
+        """
+        async_tool = self.__run_as_sync(
+            self.__async_client.load_tool(tool_name, auth_token_getters, bound_params)
+        )
+
+        if not self.__loop or not self.__thread:
+            raise ValueError("Background loop or thread cannot be None.")
+        return ToolboxSyncTool(async_tool, self.__loop, self.__thread)
+
+    def load_toolset(
+        self,
+        toolset_name: str,
+        auth_token_getters: dict[str, Callable[[], str]] = {},
+        bound_params: Mapping[str, Union[Callable[[], Any], Any]] = {},
+    ) -> list[ToolboxSyncTool]:
+        """
+        Synchronously fetches a toolset and loads all tools defined within it.
+
+        Args:
+            toolset_name: Name of the toolset to load tools.
+            auth_token_getters: A mapping of authentication service names to
+                callables that return the corresponding authentication token.
+            bound_params: A mapping of parameter names to bind to specific values or
+                callables that are called to produce values as needed.
+
+        Returns:
+            list[ToolboxSyncTool]: A list of synchronous callables, one for each
+            tool defined in the toolset.
+        """
+        async_tools = self.__run_as_sync(
+            self.__async_client.load_toolset(
+                toolset_name, auth_token_getters, bound_params
+            )
+        )
+
+        if not self.__loop or not self.__thread:
+            raise ValueError("Background loop or thread cannot be None.")
+        tools: list[ToolboxSyncTool] = []
+        for async_tool in async_tools:
+            tools.append(ToolboxSyncTool(async_tool, self.__loop, self.__thread))
+        return tools
+
+    def close(self):
+        """
+        Synchronously closes the client session if it was created internally by the client.
+        """
+        coro = self.__session.close()
+        self.__run_as_sync(coro)
+
+    def __enter__(self):
+        """Enter the runtime context related to this client instance."""
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        """Exit the runtime context and close the client session."""
+        self.close()

packages/toolbox-core/src/toolbox_core/sync_tool.py

@@ -0,0 +1,129 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import asyncio
+from asyncio import AbstractEventLoop
+from threading import Thread
+from typing import Any, Awaitable, Callable, Mapping, TypeVar, Union
+
+from .tool import ToolboxTool
+
+T = TypeVar("T")
+
+
+class ToolboxSyncTool:
+    """
+    A synchronous wrapper around an asynchronous ToolboxTool instance.
+
+    This class allows calling the underlying async tool's __call__ method
+    synchronously. It also wraps methods like `add_auth_token_getters` and
+    `bind_parameters` to ensure they return new instances of this synchronous
+    wrapper.
+    """
+
+    def __init__(
+        self, async_tool: ToolboxTool, loop: AbstractEventLoop, thread: Thread
+    ):
+        """
+        Initializes the synchronous wrapper.
+
+        Args:
+            async_tool: An instance of the asynchronous ToolboxTool.
+        """
+        if not isinstance(async_tool, ToolboxTool):
+            raise TypeError("async_tool must be an instance of ToolboxTool")
+
+        self.__async_tool = async_tool
+        self.__loop = loop
+        self.__thread = thread
+
+        # Delegate introspection attributes to the wrapped async tool
+        self.__name__ = self.__async_tool.__name__
+        self.__doc__ = self.__async_tool.__doc__
+        self.__signature__ = self.__async_tool.__signature__
+        self.__annotations__ = self.__async_tool.__annotations__
+        # TODO: self.__qualname__ ?? (Consider if needed)
+
+    def __run_as_sync(self, coro: Awaitable[T]) -> T:
+        """Run an async coroutine synchronously"""
+        if not self.__loop:
+            raise Exception(
+                "Cannot call synchronous methods before the background loop is initialized."
+            )
+        return asyncio.run_coroutine_threadsafe(coro, self.__loop).result()
+
+    async def __run_as_async(self, coro: Awaitable[T]) -> T:
+        """Run an async coroutine asynchronously"""
+
+        # If a loop has not been provided, attempt to run in current thread.
+        if not self.__loop:
+            return await coro
+
+        # Otherwise, run in the background thread.
+        return await asyncio.wrap_future(
+            asyncio.run_coroutine_threadsafe(coro, self.__loop)
+        )
+
+    def __call__(self, *args: Any, **kwargs: Any) -> str:
+        """
+        Synchronously calls the underlying remote tool.
+
+        This method blocks until the asynchronous call completes and returns
+        the result.
+
+        Args:
+            *args: Positional arguments for the tool.
+            **kwargs: Keyword arguments for the tool.
+
+        Returns:
+            The string result returned by the remote tool execution.
+
+        Raises:
+            Any exception raised by the underlying async tool's __call__ method
+            or during asyncio execution.
+        """
+        return self.__run_as_sync(self.__async_tool(**kwargs))
+
+    def add_auth_token_getters(
+        self,
+        auth_token_getters: Mapping[str, Callable[[], str]],
+    ) -> "ToolboxSyncTool":
+        """
+        Registers auth token getters and returns a new SyncToolboxTool instance.
+
+        Args:
+            auth_token_getters: A mapping of authentication service names to
+                callables that return the corresponding authentication token.
+
+        Returns:
+            A new SyncToolboxTool instance wrapping the updated async tool.
+        """
+        new_async_tool = self.__async_tool.add_auth_token_getters(auth_token_getters)
+        return ToolboxSyncTool(new_async_tool, self.__loop, self.__thread)
+
+    def bind_parameters(
+        self, bound_params: Mapping[str, Union[Callable[[], Any], Any]]
+    ) -> "ToolboxSyncTool":
+        """
+        Binds parameters and returns a new SyncToolboxTool instance.
+
+         Args:
+             bound_params: A mapping of parameter names to values or callables that
+                 produce values.
+
+         Returns:
+             A new SyncToolboxTool instance wrapping the updated async tool.
+        """
+        new_async_tool = self.__async_tool.bind_parameters(bound_params)
+        return ToolboxSyncTool(new_async_tool, self.__loop, self.__thread)