feat: add optional schema for Postgres metadata tables (#6764)

* feat(meta): add optional schema for Postgres metadata tables

- Add `schema` option to specify a custom schema for metadata tables
- Update `PgStore` and `PgElection` to support optional schema
- Modify SQL templates to use schema when provided
- Add tests for schema support in Postgres backend

Signed-off-by: Logic <zqr10159@dromara.org>

* refactor(meta): remove unused `create_schema_statement` and simplify `PgSqlTemplateFactory`

- Remove `create_schema_statement` from `PgSqlTemplateSet` struct
- Simplify `PgSqlTemplateFactory` by removing `new` method and merging it with `with_schema`
- Update related tests to reflect these changes

Signed-off-by: Logic <zqr10159@dromara.org>

* refactor(meta-srv): remove unused imports

- Remove unused import of BoxedError from common_error::ext- Remove unused import of TlsOption from servers::tls

Signed-off-by: Logic <zqr10159@dromara.org>

* build(meta): update Postgres version and add error handling imports

- Update Postgres version to 17 in docker-compose.yml
- Add BoxedError import for error handling in meta-srv

Signed-off-by: Logic <zqr10159@dromara.org>

* feat(postgres): add support for optional schema in PgElection and related components

Signed-off-by: Logic <zqr10159@dromara.org>

* feat(postgres): add support for optional schema in PgElection and related components

Signed-off-by: Logic <zqr10159@dromara.org>

* fix(develop): update Postgres schema commands to specify host

Signed-off-by: Logic <zqr10159@dromara.org>

* refactor(postgres): simplify plugin options handling and update SQL examples

Signed-off-by: Logic <zqr10159@dromara.org>

* refactor(postgres): simplify plugin options handling and update SQL examples

Signed-off-by: Logic <zqr10159@dromara.org>

* fix(postgres): update meta_election_lock_id description for optional schema support

Signed-off-by: Logic <zqr10159@dromara.org>

* fix(postgres): add health check and fallback wait for Postgres in CI setup

* fix(postgres): update Docker setup for Postgres and add support for Postgres 15

* fix(postgres): remove redundant Postgres setup step in CI configuration

* Update tests-integration/fixtures/postgres/init.sql

Co-authored-by: Weny Xu <wenymedia@gmail.com>

* Update .github/workflows/develop.yml

* Update tests-integration/fixtures/docker-compose.yml

* Update src/common/meta/src/kv_backend/rds/postgres.rs

Co-authored-by: Weny Xu <wenymedia@gmail.com>

* Update src/common/meta/src/kv_backend/rds/postgres.rs

Co-authored-by: Weny Xu <wenymedia@gmail.com>

* Update src/common/meta/src/kv_backend/rds/postgres.rs

Co-authored-by: Weny Xu <wenymedia@gmail.com>

* Update src/common/meta/src/kv_backend/rds/postgres.rs

Co-authored-by: Weny Xu <wenymedia@gmail.com>

* fix: Refactor PostgreSQL backend to support optional schema in PgStore and related SQL templates

* feat: Update PostgreSQL configuration and add PG15 specific integration tests

* feat: Update PostgreSQL configuration and add PG15 specific integration tests

* refactor(postgres): update test schemas from 'greptime_schema' to 'test_schema'

* Update .github/workflows/develop.yml

* refactor: minor factor

Signed-off-by: WenyXu <wenymedia@gmail.com>

* chore: apply suggestions

Signed-off-by: WenyXu <wenymedia@gmail.com>

* fix: fix unit test

Signed-off-by: WenyXu <wenymedia@gmail.com>

---------

Signed-off-by: Logic <zqr10159@dromara.org>
Signed-off-by: WenyXu <wenymedia@gmail.com>
Co-authored-by: Weny Xu <wenymedia@gmail.com>

tests-integration/fixtures/docker-compose.yml

@@ -94,6 +94,19 @@ services:
       - POSTGRES_DB=postgres
       - POSTGRES_PASSWORD=admin
 
+  postgres15:
+    image: docker.io/postgres:15-alpine
+    ports:
+        - 5433:5432
+    volumes:
+        - ~/apps/postgres15:/var/lib/postgresql/data
+        - ./postgres/init.sql:/docker-entrypoint-initdb.d/01-init.sql:ro
+    environment:
+        - POSTGRES_USER=greptimedb
+        - POSTGRES_DB=postgres
+        - POSTGRES_PASSWORD=admin
+
+
   mysql:
     image: bitnami/mysql:5.7
     ports:

tests-integration/fixtures/postgres/init.sql

@@ -0,0 +1,10 @@
+-- 1. Create a non-superuser
+CREATE USER test_user WITH PASSWORD 'test_password';
+
+-- 2. Prevent non-superusers from creating tables in the public schema
+-- Explicitly revoke CREATE permission from PUBLIC to avoid inherited grants
+REVOKE CREATE ON SCHEMA public FROM PUBLIC;
+REVOKE CREATE ON SCHEMA public FROM test_user;
+
+-- 3. Create a separate schema owned by the non-superuser
+CREATE SCHEMA test_schema AUTHORIZATION test_user;