feat(memory): add SQLite and MySQL short-term memory backends

[wucm667]

Summary

Add SQLite and MySQL backends for short-term memory in VeADK-Go, closing the feature gap with the Python SDK.

Changes

New files

• memory/short_term_memory_backends/sqlite_backend.go — SQLite backend; falls back to an in-memory database (file::memory:?cache=shared) when DBUrl is empty
• memory/short_term_memory_backends/sqlite_backend_test.go — unit tests for the SQLite backend
• memory/short_term_memory_backends/mysql_backend.go — MySQL backend; accepts either a pre-built DBUrl or individual fields (host/port/user/password/database); URL-encodes credentials automatically to handle special characters
• memory/short_term_memory_backends/mysql_backend_test.go — unit tests for the MySQL backend

Modified files

• common/consts.go — add DATABASE_SQLITE_DBURL and DATABASE_MYSQL_* env key constants
• configs/database.go — add Sqlite and Mysql fields to DatabaseConfig; map env vars in MapEnvToConfig
• configs/configs.go — initialize Sqlite and Mysql config structs in SetupVeADKConfig
• memory/short_term_memory.go — extend NewShortTermMemoryService factory with BackendShortTermSQLite and BackendShortTermMySQL cases
• go.mod / go.sum — add gorm.io/driver/sqlite v1.6.0 and gorm.io/driver/mysql v1.6.0

Usage

SQLite via environment variables:

DATABASE_SQLITE_DBURL=/path/to/veadk.db

svc, err := memory.NewShortTermMemoryService(memory.BackendShortTermSQLite, nil)

MySQL via environment variables:

DATABASE_MYSQL_HOST=127.0.0.1
DATABASE_MYSQL_PORT=3306
DATABASE_MYSQL_USER=root
DATABASE_MYSQL_PASSWORD=secret
DATABASE_MYSQL_DATABASE=veadk

svc, err := memory.NewShortTermMemoryService(memory.BackendShortTermMySQL, nil)

Or via config.yaml:

database:
  sqlite:
    db_url: /path/to/veadk.db
  mysql:
    host: 127.0.0.1
    port: "3306"
    user: root
    password: secret
    database: veadk

Testing

go test -v -race ./memory/short_term_memory_backends/...
go test -v -race ./memory/...

Notes

• Mirrors the BackendShortTermSQLite and BackendShortTermMySQL backends already available in the Python SDK
• Follows the same patterns as the existing PostgreSQL backend (postgresql_backend.go)
• Tests mock the GORM layer with github.com/bytedance/mockey; no real database required

[Copilot]

Pull request overview

Adds SQLite and MySQL implementations for the short-term memory session store to bring VeADK-Go closer to feature parity with the Python SDK, including config/env wiring and backend selection in the short-term memory factory.

Changes:

• Introduces new sqlite and mysql short-term memory backends using GORM drivers.
• Extends configuration/env mapping to support SQLite/MySQL connection settings.
• Updates the short-term memory backend factory to route to the new backends; adds module dependencies for the new DB drivers.

Reviewed changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
memory/short_term_memory_backends/sqlite_backend.go	New SQLite STM backend with in-memory fallback when DBUrl is empty.
memory/short_term_memory_backends/sqlite_backend_test.go	Unit tests for the SQLite backend wiring/mocking.
memory/short_term_memory_backends/mysql_backend.go	New MySQL STM backend with DSN construction and credential escaping.
memory/short_term_memory_backends/mysql_backend_test.go	Unit tests for the MySQL backend wiring/mocking.
memory/short_term_memory.go	Adds sqlite/mysql backend options to the STM service factory.
configs/database.go	Adds SQLite/MySQL fields to DatabaseConfig and maps env vars into them.
configs/configs.go	Initializes SQLite/MySQL config structs in global setup.
common/consts.go	Adds env key constants for SQLite and MySQL settings.
go.mod / go.sum	Adds GORM SQLite/MySQL drivers and their transitive deps.

Comments suppressed due to low confidence (3)

memory/short_term_memory_backends/mysql_backend_test.go:32

• wantDBurl is populated but never asserted, so this test doesn't verify DSN generation/credential encoding when DBUrl is empty. Add an assertion against the generated DSN (e.g., tt.config.DBUrl after calling NewMysqlSTMBackend, or by capturing the argument passed to mysql.Open/database.NewSessionService).

	tests := []struct {
		name      string
		config    *MysqlBackendConfig
		wantDBurl string
		wantErr   bool
	}{

memory/short_term_memory_backends/sqlite_backend_test.go:47

• The "empty db url uses in-memory" case doesn't assert that the fallback DSN (file::memory:?cache=shared) was actually applied. Consider asserting the updated tt.config.DBUrl (or capturing the dialector argument passed into database.NewSessionService) to ensure the intended behavior is covered.

		{
			name: "empty db url uses in-memory",
			config: &SqliteBackendConfig{
				CommonDatabaseConfig: &configs.CommonDatabaseConfig{
					DBUrl: "",
				},
			},
		},

go.mod:82

• Adding github.com/mattn/go-sqlite3 (via gorm.io/driver/sqlite) introduces a CGO dependency, which can break builds in environments where CGO_ENABLED=0 or when cross-compiling. If CGO-free builds are a goal for this repo, consider a pure-Go SQLite driver alternative or document the CGO requirement for the SQLite backend.

	github.com/jtolds/gls v4.20.0+incompatible // indirect
	github.com/klauspost/cpuid/v2 v2.2.9 // indirect
	github.com/mattn/go-isatty v0.0.20 // indirect
	github.com/mattn/go-sqlite3 v1.14.22 // indirect
	github.com/mitchellh/mapstructure v1.5.0 // indirect

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.