feature/auto-create-new-session
Merge https://github.com/google/adk-python/pull/4072
**Please ensure you have read the [contribution guide](https://github.com/google/adk-python/blob/main/CONTRIBUTING.md) before creating a pull request.**
### Link to Issue or Description of Change
**2. Or, if no issue exists, describe the change:**
**Problem:**
When building frontend applications with ADK, there's a limitation where frontends cannot always guarantee that `create_session` is called before initiating a conversation. This creates friction in the user experience because:
- Users may refresh the page or navigate directly to a conversation URL with a specific session_id
- Frontend state management may lose track of whether a session was already created
- Mobile apps or single-page applications have complex lifecycle management where ensuring `create_session` is called first adds unnecessary complexity
- This forces developers to implement additional logic to check session existence before every conversation
Currently, if `get_session` is called with a non-existent session_id, it returns `None`, requiring the frontend to explicitly handle this case and call `create_session` separately.
**Solution:**
Modified the `get_session` method in `DatabaseSessionService` to automatically create a session if it doesn't exist in the database. This "get or create" pattern is common in many frameworks and provides a more developer-friendly API.
The implementation:
1. Attempts to fetch the session from the database
2. If the session doesn't exist (returns `None`), automatically calls `create_session` with the provided parameters
3. Retrieves and returns the newly created session
4. Maintains backward compatibility - existing code continues to work without changes
This allows frontends to simply call `get_session` with a session_id and be confident that the session will be available, regardless of whether it was previously created.
**Benefits:**
- Simplifies frontend integration by removing the need to track session creation state
- Reduces API calls (no need to check existence before calling get_session)
- Follows the principle of least surprise - getting a session with an ID should work reliably
- No breaking changes to existing code that checks for `None` return values
### Testing Plan
**Unit Tests:**
- [x] I have added or updated unit tests for my change.
- [x] All unit tests pass locally.
**pytest results:**
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/4072 from lwangverizon:feature/auto-create-new-session 5475c6ae91d12332598d521302736eb1db79a8be
PiperOrigin-RevId: 856019482
Merge https://github.com/google/adk-python/pull/3745
This change enables Agent Engine deployments to use App objects with event compaction and context caching configs while using the Agent Engine resource name for session operations, rather than App.name.
- Allow app_name parameter to override app.name when both are provided
- Still error when app and agent are both provided (prevents confusion)
- Updated tests to reflect new behavior and added test for override case
- Updateed documentation to clarify the new usage pattern
This fixes the issue where App.name (a simple identifier) conflicts with Agent Engine's requirement for resource names in session creation.
Related to issue #3715
**Please ensure you have read the [contribution guide](https://github.com/google/adk-python/blob/main/CONTRIBUTING.md) before creating a pull request.**
### Link to Issue or Description of Change
**1. Link to an existing issue (if applicable):**
- Closes: #3715
- Related: #3715
**2. Or, if no issue exists, describe the change:**
_If applicable, please follow the issue templates to provide as much detail as
possible._
**Problem:**
When deploying an agent to Agent Engine with event compaction and/or context caching enabled, users must wrap their agent in an `App` object to configure these features. However, when the `App` is passed to `AdkApp` and deployed, session creation fails because:
1. `App.name` is validated as a simple Python identifier (e.g., `"my_agent_name"`) via `validate_app_name()`
2. Agent Engine expects the app name to be either a full Reasoning Engine resource name (e.g., `"projects/123/locations/us-central1/reasoningEngines/456"`) or the reasoning engine ID
3. When an `App` object is passed to `AdkApp`, the deployment stores `App.name` (the simple identifier), but session creation later rejects it as invalid
This prevents users from deploying to Agent Engine with event compaction or context caching enabled.
**Solution:**
Allow the `app_name` parameter in `Runner.__init__()` to override `app.name` when both are provided. This enables Agent Engine (and other deployment scenarios) to:
- Pass the full `App` object to preserve event compaction and context caching configurations
- Override `app.name` with the Agent Engine resource name for session operations
- Successfully create sessions using the resource name while maintaining App-level features
The change is backward compatible: existing code that only provides `app` continues to use `app.name` as before. The override only applies when `app_name` is explicitly provided along with `app`.
### Testing Plan
_Please describe the tests that you ran to verify your changes. This is required
for all PRs that are not small documentation or typo fixes._
**Unit Tests:**
- [x] I have added or updated unit tests for my change.
- [x] All unit tests pass locally.
1. **Updated existing test** (`test_runner_init_raises_error_with_app_and_agent`):
- Changed from testing `app` + `app_name` + `agent` error to testing only `app` + `agent` error
- Verifies that `app` and `agent` cannot both be provided (prevents confusion)
2. **Added new test** (`test_runner_init_allows_app_name_override_with_app`):
- Verifies that `app_name` can override `app.name` when both are provided
- Confirms that `runner.app_name == "override_name"` while `runner.app` still references the original App object
- Ensures all App configs (agent, plugins, context_cache_config, etc.) are preserved
```
pytest tests/unittests/test_runners.py::TestRunnerWithPlugins::test_runner_init_raises_error_with_app_and_agent -v
pytest tests/unittests/test_runners.py::TestRunnerWithPlugins::test_runner_init_allows_app_name_override_with_app -v
```
tests/unittests/test_runners.py::TestRunnerWithPlugins::test_runner_init_allows_app_name_override_with_app PASSED [100%]
tests/unittests/test_runners.py::TestRunnerWithPlugins::test_runner_init_raises_error_with_app_and_agent PASSED [100%]
**Manual End-to-End (E2E) Tests:**
1. Create an agent with event compaction and context caching:
```python
from google.adk import Agent
from google.adk.apps import App
from google.adk.apps import EventsCompactionConfig
from google.adk.agents import ContextCacheConfig
root_agent = Agent(
name="my_agent",
model="gemini-2.5-flash",
instruction="You are a helpful assistant.",
)
app = App(
name="my_agent",
root_agent=root_agent,
events_compaction_config=EventsCompactionConfig(
compaction_interval=2,
overlap_size=1,
),
context_cache_config=ContextCacheConfig(),
)
```
2. Create a Runner with app and override app_name:
```python
from google.adk import Runner
from google.adk.sessions import InMemorySessionService
from google.adk.artifacts import InMemoryArtifactService
runner = Runner(
app=app,
app_name="projects/123/locations/us-central1/reasoningEngines/456", # Resource name
session_service=InMemorySessionService(),
artifact_service=InMemoryArtifactService(),
)
# Verify app_name override worked
assert runner.app_name == "projects/123/locations/us-central1/reasoningEngines/456"
assert runner.app == app # Original app object preserved
assert runner.context_cache_config is not None # Config preserved
assert runner.app.events_compaction_config is not None # Config preserved
```
3. Verify session creation uses the overridden name:
```python
session = await runner.session_service.create_session(
app_name=runner.app_name, # Uses resource name, not app.name
user_id="test_user",
)
```
**Expected Results:**
- Runner creation succeeds with both `app` and `app_name` provided
- `runner.app_name` equals the provided `app_name` (not `app.name`)
- All App configurations (event compaction, context caching) are preserved
- Session creation uses the overridden `app_name`
### Checklist
- [x] I have read the [CONTRIBUTING.md](https://github.com/google/adk-python/blob/main/CONTRIBUTING.md) document.
- [x] I have performed a self-review of my own code.
- [x] I have commented my code, particularly in hard-to-understand areas.
- [x] I have added tests that prove my fix is effective or that my feature works.
- [x] New and existing unit tests pass locally with my changes.
- [x] I have manually tested my changes end-to-end.
- [x] Any dependent changes have been merged and published in downstream modules.
### Additional context
**Backward Compatibility:**
This change is fully backward compatible. All existing code patterns continue to work:
- `Runner(app=my_app)` → Still uses `app.name`
- `Runner(app_name="x", agent=my_agent)` → Still works
- `Runner(app=my_app, app_name=None)` → Still works (uses `app.name`)
**Impact on Agent Engine:**
This change enables Agent Engine deployments to support event compaction and context caching. Once this PR is merged, Agent Engine SDK should:
1. Accept `App` objects from `AdkApp(app=my_app, ...)`
2. Create `Runner` with both `app` and `app_name` (resource name):
```python
runner = Runner(
app=my_app, # Preserves event_compaction_config and context_cache_config
app_name=resource_name, # Overrides app.name for session operations
session_service=session_service,
...
)
```
3. Event compaction and context caching will work automatically once the App is passed correctly.
**Related Documentation:**
- Event compaction is documented in `src/google/adk/apps/compaction.py`
- Context caching is documented in `src/google/adk/agents/context_cache_config.py`
- The Runner's App support is documented in `src/google/adk/runners.py`
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/3745 from sarojrout:feat/agent-engine-app-name-override 22d91d59df1460d25d06a71e155ad3dc20a69ca8
PiperOrigin-RevId: 854325898
Adds a method to merge custom metadata from the RunConfig into each Event. This metadata is applied to events generated by the agent, early exit events, and the initial user message event.
Close#3953
Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 852433171
When users instantiate LlmAgent directly (not subclassed), the origin inference incorrectly detected ADK's internal google/adk/agents/ path as a mismatch.
Use metadata from AgentLoader when available
Skip inference for google.adk.* module
Close#3143
Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 842774292
This change introduces a shutdown lifecycle hook for plugins. The `PluginManager` now has an `async def shutdown()` method that will call `await plugin.shutdown()` on any registered plugins that implement the method. This is called from `Runner.close()`, allowing plugins to perform cleanup tasks like flushing logs or closing connections when the runner instance is being closed. This improves the reliability of plugins that perform background operations.
PiperOrigin-RevId: 831037737
In `gemini_llm_connection.py`, accumulate partial transcription texts and emit `LlmResponse` with `partial=True` for each chunk. When the transcription is marked as `finished`, emit a final `LlmResponse` with the full accumulated text and `partial=False`.
In `runners.py`, modify `_should_append_to_history` to only add transcription events to the history when they are fully finished, preventing partial transcriptions from being added.
Co-authored-by: Hangfei Lin <hangfei@google.com>
PiperOrigin-RevId: 829029715
- let _enforce_app_name_alignment warn instead of raising while caching the hint that now augments the existing “Session not found …” error
- tighten _infer_agent_origin so it ignores hidden folders (like .venv)
- make AgentTool reuse the parent runner’s app_name, stopping internal runners from conflicting in multi-agent setups
PiperOrigin-RevId: 822205860
Update plugin manager and built-in plugins to prioritize CallbackContext. Keep InvocationContext access for legacy plugins with adapter. Change callback docs/tests to cover the new context.
PiperOrigin-RevId: 818822267
Update plugin manager and built-in plugins to prioritize CallbackContext. Keep InvocationContext access for legacy plugins with adapter. Change callback docs/tests to cover the new context.
PiperOrigin-RevId: 818798087
1. add a context cache config in app level which will apply to all agents in the app
2. pass on cache config through invocation context to llm_reqeust
3. store cache metadata in llm_response
4. lookup old cache metadata from latest event for reusing old cache
5. create new cache if old cache cannot be reused
PiperOrigin-RevId: 809158578
These tests verify that `ValueError` is raised when `Runner` is initialized without providing either an `app` instance or both `app_name` and `agent`.
PiperOrigin-RevId: 805427256
- Added `tests/unittests/apps/test_apps.py` with basic tests for `App` initialization.
- Modified `tests/unittests/test_runners.py` to include a test that verifies `Runner` raises a `ValueError` when both `app` and `app_name` are provided during initialization.
PiperOrigin-RevId: 803556826
This change integrates the plugin system with ADK. PluginManager is attached to the invocation context similar to session/artifact/memory.
It includes integrations with following ADK internal callbacks:
* App callbacks: Integrated in the BaseRunner class, in run_async and run_live
* On Message callbacks: Integrated in the BaseRunner class, triggers on run_async.
* Agent callbacks: Integrated in the BaseAgent class. Leveraging the existing *callback functions
* Model callbacks: Integrating in the base_llm_flow.
* Tool callbacks: Integrated in functions.py, wrapped around the code for agent tool_callbacks
Sample code to use plugins:
```python
# Add plugins to Runner
runner = Runner(
app_name="my-app",
agent=root_agent,
artifact_service=artifact_service,
session_service=session_service,
memory_service=memory_service,
plugins=[
MySamplePlugin(),
LoggingPlugin(),
],
)
```
PiperOrigin-RevId: 781746586