Add database session service

core/package.json

@@ -42,6 +42,8 @@
   "dependencies": {
     "@a2a-js/sdk": "^0.3.10",
     "@google/genai": "^1.37.0",
+    "@mikro-orm/core": "^6.6.6",
+    "@mikro-orm/reflection": "^6.6.6",
     "@modelcontextprotocol/sdk": "^1.26.0",
     "google-auth-library": "^10.3.0",
     "lodash-es": "^4.17.23",
@@ -50,12 +52,18 @@
   },
   "devDependencies": {
     "@types/lodash-es": "^4.17.12",
-    "openapi-types": "^12.1.3"
+    "openapi-types": "^12.1.3",
+    "@mikro-orm/sqlite": "^6.6.6"
   },
   "peerDependencies": {
     "@google-cloud/opentelemetry-cloud-monitoring-exporter": "^0.21.0",
     "@google-cloud/opentelemetry-cloud-trace-exporter": "^3.0.0",
     "@google-cloud/storage": "^7.17.1",
+    "@mikro-orm/mariadb": "^6.6.6",
+    "@mikro-orm/mssql": "^6.6.6",
+    "@mikro-orm/mysql": "^6.6.6",
+    "@mikro-orm/postgresql": "^6.6.6",
+    "@mikro-orm/sqlite": "^6.6.6",
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/api-logs": "^0.205.0",
     "@opentelemetry/exporter-logs-otlp-http": "^0.205.0",

core/src/common.ts

@@ -46,6 +46,14 @@ export {StreamingMode} from './agents/run_config.js';
 export type {RunConfig} from './agents/run_config.js';
 export {SequentialAgent, isSequentialAgent} from './agents/sequential_agent.js';
 export type {TranscriptionEntry} from './agents/transcription_entry.js';
+export type {
+  BaseArtifactService,
+  DeleteArtifactRequest,
+  ListArtifactKeysRequest,
+  ListVersionsRequest,
+  LoadArtifactRequest,
+  SaveArtifactRequest,
+} from './artifacts/base_artifact_service.js';
 export {InMemoryArtifactService} from './artifacts/in_memory_artifact_service.js';
 export {AuthCredentialTypes} from './auth/auth_credential.js';
 export type {
@@ -97,6 +105,11 @@ export {
   isBaseExampleProvider,
 } from './examples/base_example_provider.js';
 export type {Example} from './examples/example.js';
+export type {
+  BaseMemoryService,
+  SearchMemoryRequest,
+  SearchMemoryResponse,
+} from './memory/base_memory_service.js';
 export {InMemoryMemoryService} from './memory/in_memory_memory_service.js';
 export type {MemoryEntry} from './memory/memory_entry.js';
 export {ApigeeLlm} from './models/apigee_llm.js';
@@ -127,13 +140,28 @@ export type {
 export {InMemoryRunner} from './runner/in_memory_runner.js';
 export {Runner} from './runner/runner.js';
 export type {RunnerConfig} from './runner/runner.js';
+export {BaseSessionService} from './sessions/base_session_service.js';
+export type {
+  AppendEventRequest,
+  CreateSessionRequest,
+  DeleteSessionRequest,
+  GetSessionConfig,
+  GetSessionRequest,
+  ListSessionsRequest,
+  ListSessionsResponse,
+} from './sessions/base_session_service.js';
 export {InMemorySessionService} from './sessions/in_memory_session_service.js';
 export {createSession} from './sessions/session.js';
 export type {Session} from './sessions/session.js';
 export {State} from './sessions/state.js';
 export {AgentTool, isAgentTool} from './tools/agent_tool.js';
 export type {AgentToolConfig} from './tools/agent_tool.js';
 export {BaseTool, isBaseTool} from './tools/base_tool.js';
+export type {
+  BaseToolParams,
+  RunAsyncToolRequest,
+  ToolProcessLlmRequest,
+} from './tools/base_tool.js';
 export {BaseToolset} from './tools/base_toolset.js';
 export type {ToolPredicate} from './tools/base_toolset.js';
 export {FunctionTool, isFunctionTool} from './tools/function_tool.js';

core/src/index.ts

@@ -8,6 +8,7 @@ export {FileArtifactService} from './artifacts/file_artifact_service.js';
 export {GcsArtifactService} from './artifacts/gcs_artifact_service.js';
 export {getArtifactServiceFromUri} from './artifacts/registry.js';
 export * from './common.js';
+export {DatabaseSessionService} from './sessions/database_session_service.js';
 export {getSessionServiceFromUri} from './sessions/registry.js';
 export * from './telemetry/google_cloud.js';
 export * from './telemetry/setup.js';

core/src/sessions/base_session_service.ts

@@ -4,6 +4,8 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+import {cloneDeep} from 'lodash-es';
+
 import {Event} from '../events/event.js';
 
 import {Session} from './session.js';
@@ -163,6 +165,8 @@ export abstract class BaseSessionService {
       return event;
     }
 
+    event = trimTempDeltaState(event);
+
     this.updateSessionState({session, event});
     session.events.push(event);
 
@@ -186,3 +190,46 @@ export abstract class BaseSessionService {
     }
   }
 }
+
+/**
+ * Removes temporary state delta keys from the event.
+ */
+export function trimTempDeltaState(event: Event): Event {
+  if (!event.actions || !event.actions.stateDelta) {
+    return event;
+  }
+
+  const stateDelta = event.actions.stateDelta;
+  const filteredStateDelta: Record<string, unknown> = {};
+  for (const [key, value] of Object.entries(stateDelta)) {
+    if (!key.startsWith(State.TEMP_PREFIX)) {
+      filteredStateDelta[key] = value;
+    }
+  }
+
+  event.actions.stateDelta = filteredStateDelta;
+  return event;
+}
+
+/**
+ * Merges app state, user state, and session state.
+ *
+ * @param appState The application state.
+ * @param userState The user state.
+ * @param sessionState The session state.
+ * @return The merged state.
+ */
+export function mergeStates(
+  appState: Record<string, unknown> = {},
+  userState: Record<string, unknown> = {},
+  sessionState: Record<string, unknown> = {},
+) {
+  const merged = cloneDeep(sessionState);
+  for (const [k, v] of Object.entries(appState)) {
+    merged[State.APP_PREFIX + k] = v;
+  }
+  for (const [k, v] of Object.entries(userState)) {
+    merged[State.USER_PREFIX + k] = v;
+  }
+  return merged;
+}