feat(agent-runner): add plugin runner host integration

src/langbot/pkg/agent/runner/registry.py

@@ -0,0 +1,273 @@
+"""Agent runner registry for discovering and caching runner descriptors."""
+
+from __future__ import annotations
+
+import typing
+import asyncio
+
+from langbot_plugin.api.entities.builtin.agent_runner.manifest import (
+    AgentRunnerManifest,
+)
+
+from ...core import app
+from .descriptor import AgentRunnerDescriptor
+from .id import parse_runner_id, format_runner_id
+from .errors import RunnerNotFoundError, RunnerNotAuthorizedError
+
+
+class AgentRunnerRegistry:
+    """Registry for discovering and managing agent runners.
+
+    Responsibilities:
+    - Discover runners from plugin runtime via LIST_AGENT_RUNNERS
+    - Validate runner manifests (kind, metadata, spec)
+    - Cache discovered runners for performance
+    - Filter runners by bound plugins
+    - Handle manifest errors gracefully (log warning, skip runner)
+    """
+
+    ap: app.Application
+
+    _cache: dict[str, AgentRunnerDescriptor] | None
+    """Cached runner descriptors keyed by runner ID"""
+
+    _cache_lock: asyncio.Lock
+    """Lock for cache refresh operations"""
+
+    def __init__(self, ap: app.Application):
+        self.ap = ap
+        self._cache = None
+        self._cache_lock = asyncio.Lock()
+
+    async def _discover_runners(self) -> dict[str, AgentRunnerDescriptor]:
+        """Discover runners from plugin runtime.
+
+        Always discovers ALL runners (no bound_plugins filter).
+        The cache should contain unfiltered discovery results.
+
+        Returns:
+            Dict of runner descriptors keyed by runner ID
+        """
+        if not self.ap.plugin_connector.is_enable_plugin:
+            return {}
+
+        runners: dict[str, AgentRunnerDescriptor] = {}
+
+        try:
+            # Always list all runners (bound_plugins=None)
+            plugin_runners = await self.ap.plugin_connector.list_agent_runners(None)
+
+            for runner_data in plugin_runners:
+                try:
+                    descriptor = self._validate_and_build_descriptor(runner_data)
+                    if descriptor is not None:
+                        runners[descriptor.id] = descriptor
+                except Exception as e:
+                    plugin_author = runner_data.get('plugin_author', 'unknown')
+                    plugin_name = runner_data.get('plugin_name', 'unknown')
+                    runner_name = runner_data.get('runner_name', 'unknown')
+                    self.ap.logger.warning(
+                        f'Invalid runner manifest for plugin:{plugin_author}/{plugin_name}/{runner_name}: {e}'
+                    )
+                    continue
+
+        except Exception as e:
+            self.ap.logger.warning(f'Failed to list agent runners from plugin runtime: {e}')
+            return {}
+
+        return runners
+
+    def _validate_and_build_descriptor(self, runner_data: dict[str, typing.Any]) -> AgentRunnerDescriptor | None:
+        """Validate runner manifest and build descriptor.
+
+        Args:
+            runner_data: Raw runner data from plugin runtime with fields:
+                - plugin_author, plugin_name, runner_name
+                - manifest (typed AgentRunnerManifest)
+
+        Returns:
+            AgentRunnerDescriptor if valid, None if invalid
+        """
+        plugin_author = runner_data.get('plugin_author', '')
+        plugin_name = runner_data.get('plugin_name', '')
+        runner_name = runner_data.get('runner_name', '')
+
+        if not plugin_author or not plugin_name or not runner_name:
+            return None
+
+        manifest = runner_data.get('manifest', {})
+        runner_id = format_runner_id(
+            source='plugin',
+            plugin_author=plugin_author,
+            plugin_name=plugin_name,
+            runner_name=runner_name,
+        )
+
+        typed_manifest = AgentRunnerManifest.model_validate(manifest)
+        config_schema = [
+            item.model_dump(mode='json') for item in typed_manifest.config_schema
+        ]
+
+        return AgentRunnerDescriptor(
+            id=runner_id,
+            source='plugin',
+            label=typed_manifest.label,
+            description=typed_manifest.description,
+            plugin_author=plugin_author,
+            plugin_name=plugin_name,
+            runner_name=runner_name,
+            plugin_version=runner_data.get('plugin_version'),
+            config_schema=config_schema,
+            capabilities=typed_manifest.capabilities,
+            permissions=typed_manifest.permissions,
+            raw_manifest=manifest,
+        )
+
+    async def refresh(self) -> None:
+        """Refresh runner cache.
+
+        Always discovers ALL runners (no bound_plugins filter).
+        The cache contains unfiltered discovery results.
+        """
+        async with self._cache_lock:
+            self._cache = await self._discover_runners()
+
+    async def list_runners(
+        self,
+        bound_plugins: list[str] | None = None,
+        use_cache: bool = True,
+    ) -> list[AgentRunnerDescriptor]:
+        """List available runners.
+
+        Args:
+            bound_plugins: Optional filter for bound plugins (applied locally)
+            use_cache: Use cached data if available
+
+        Returns:
+            List of runner descriptors
+        """
+        if use_cache and self._cache is not None:
+            # Filter from cache
+            return self._filter_runners_by_bound_plugins(self._cache, bound_plugins)
+
+        # Discover fresh (always full list)
+        runners = await self._discover_runners()
+
+        # Update cache (full list, unfiltered)
+        async with self._cache_lock:
+            self._cache = runners
+
+        # Filter locally
+        return self._filter_runners_by_bound_plugins(runners, bound_plugins)
+
+    def _filter_runners_by_bound_plugins(
+        self,
+        runners: dict[str, AgentRunnerDescriptor],
+        bound_plugins: list[str] | None,
+    ) -> list[AgentRunnerDescriptor]:
+        """Filter runners by bound plugins.
+
+        Args:
+            runners: Dict of runner descriptors
+            bound_plugins: Optional filter (None means all plugins allowed)
+
+        Returns:
+            Filtered list of runner descriptors
+        """
+        if bound_plugins is None:
+            # All plugins allowed
+            return list(runners.values())
+
+        allowed_plugin_ids = set(bound_plugins)
+        filtered = []
+        for descriptor in runners.values():
+            plugin_id = descriptor.get_plugin_id()
+            if plugin_id in allowed_plugin_ids:
+                filtered.append(descriptor)
+
+        return filtered
+
+    async def get(
+        self,
+        runner_id: str,
+        bound_plugins: list[str] | None = None,
+    ) -> AgentRunnerDescriptor:
+        """Get a specific runner descriptor.
+
+        Args:
+            runner_id: Runner ID to lookup
+            bound_plugins: Optional bound plugins filter
+
+        Returns:
+            AgentRunnerDescriptor
+
+        Raises:
+            RunnerNotFoundError: If runner not found
+            RunnerNotAuthorizedError: If runner not in bound plugins
+        """
+        # Parse and validate runner ID format
+        try:
+            parse_runner_id(runner_id)
+        except ValueError as e:
+            raise RunnerNotFoundError(runner_id) from e
+
+        # Get from cache or discover (always full list)
+        if self._cache is None:
+            await self.refresh()
+
+        if self._cache is None:
+            raise RunnerNotFoundError(runner_id)
+
+        descriptor = self._cache.get(runner_id)
+        if descriptor is None:
+            raise RunnerNotFoundError(runner_id)
+
+        # Check authorization
+        if bound_plugins is not None:
+            plugin_id = descriptor.get_plugin_id()
+            if plugin_id not in bound_plugins:
+                raise RunnerNotAuthorizedError(runner_id, bound_plugins)
+
+        return descriptor
+
+    async def get_runner_metadata_for_pipeline(self) -> list[dict[str, typing.Any]]:
+        """Get runner metadata for pipeline configuration UI.
+
+        Returns runner options and their config schemas for the DynamicForm.
+        """
+        # Get all runners (no bound plugin filter for metadata listing)
+        runners = await self.list_runners(bound_plugins=None)
+
+        options = []
+        stages = []
+
+        for descriptor in runners:
+            config_schema = []
+            for index, config_item in enumerate(descriptor.config_schema):
+                item = dict(config_item)
+                if not item.get('id'):
+                    item_name = item.get('name') or str(index)
+                    item['id'] = f'{descriptor.id}.{item_name}'
+                config_schema.append(item)
+
+            # Add runner option
+            options.append(
+                {
+                    'name': descriptor.id,
+                    'label': descriptor.label,
+                    'description': descriptor.description,
+                }
+            )
+
+            # Add config schema as stage if not empty
+            if descriptor.config_schema:
+                stages.append(
+                    {
+                        'name': descriptor.id,
+                        'label': descriptor.label,
+                        'description': descriptor.description,
+                        'config': config_schema,
+                    }
+                )
+
+        return options, stages