Warning

This version of ScalarDB is no longer supported. For details, see the Release Support Policy.

ScalarDB Deployment Sample on Kubernetes (Multi-Storage Transactions)

Version

This sample uses the following versions of each product.

  • ScalarDB Server v3.6.0
  • ScalarDB SQL CLI v3.6.0
  • Scalar Envoy v1.2.0
  • MySQL v8.0.30
  • PostgreSQL v14.4
  • Helm Chart: scalar-labs/scalardb v2.3.0
  • Helm Chart: scalar-labs/envoy v2.0.1
  • Helm Chart: bitnami/mysql v9.2.6
  • Helm Chart: bitnami/postgresql v11.6.26

Environment

This sample creates the following environment on Kubernetes cluster.

+----------------------------------------------------------------------------------------------------------------------------------------------+
| [Kubernetes Cluster]                                                                                                                         |
|                                         [Pod]                                                 [Pod]                            [Pod]         |
|                                                                                                                                              |
|                                       +-------+                                         +-----------------+                                  |
|                                 +---> | Envoy | ---+                              +---> | ScalarDB Server | ---+         +----------------+  |
|                                 |     +-------+    |                              |     +-----------------+    |         |     MySQL      |  |
|                                 |                  |                              |                            |   +---> | (schema0.tbl0) |  |
|  +--------+      +---------+    |     +-------+    |     +-------------------+    |     +-----------------+    |   |     +----------------+  |
|  | Client | ---> | Service | ---+---> | Envoy | ---+---> |      Service      | ---+---> | ScalarDB Server | ---+---+                         |
|  +--------+      | (Envoy) |    |     +-------+    |     | (ScalarDB Server) |    |     +-----------------+    |   |     +----------------+  |
|                  +---------+    |                  |     +-------------------+    |                            |   +---> |   PostgreSQL   |  |
|                                 |     +-------+    |                              |     +-----------------+    |         | (schema1.tbl1) |  |
|                                 +---> | Envoy | ---+                              +---> | ScalarDB Server | ---+         +----------------+  |
|                                       +-------+                                         +-----------------+                                  |
|                                                                                                                                              |
+----------------------------------------------------------------------------------------------------------------------------------------------+

Preparation

  1. Get sample files.
    git clone https://github.com/scalar-labs/helm-charts.git
    cd helm-charts/docs/samples/scalardb/scalardb-multi-storage-sample/
    
  2. Add Helm repositories.
    helm repo add bitnami https://charts.bitnami.com/bitnami
    
    helm repo add scalar-labs https://scalar-labs.github.io/helm-charts
    
  3. Create a secret resource to access private container registry (GitHub Packages).
    kubectl create secret docker-registry reg-docker-secrets \
      --docker-server=ghcr.io \
      --docker-username=<USERNAME> \
      --docker-password=<GITHUB_PERSONAL_ACCESS_TOKEN>
    
  4. Deploy MySQL.
    helm install mysql-scalardb bitnami/mysql \
      --set auth.rootPassword=mysql \
      --set primary.persistence.enabled=false \
      --version 9.2.6
    
  5. Deploy PostgreSQL.
    helm install postgresql-scalardb bitnami/postgresql \
      --set auth.postgresPassword=postgres \
      --set primary.persistence.enabled=false \
      --version 11.6.26
    

Deploy ScalarDB Server

  1. Create a secret resource that includes DB credentials.
    kubectl create secret generic scalardb-credentials-secret \
      --from-literal=SCALAR_DB_MYSQL_USERNAME=root \
      --from-literal=SCALAR_DB_MYSQL_PASSWORD=mysql \
      --from-literal=SCALAR_DB_POSTGRES_USERNAME=postgres \
      --from-literal=SCALAR_DB_POSTGRES_PASSWORD=postgres
    
  2. Deploy ScalarDB Server
    helm install scalardb scalar-labs/scalardb \
      -f ./scalardb-server.yaml \
      --version 2.3.0
    

Deploy Client (ScalarDB SQL CLI container)

  1. Create a configmap resource that includes database.properties.
    kubectl create configmap database-properties \
      --from-file=./database.properties
    
  2. Deploy ScalarDB SQL CLI container.
    kubectl apply -f ./scalardb-sql-cli.yaml
    

Run SQL using ScalarDB SQL CLI

  1. Run ScalarDB SQL CLI.
    kubectl exec -it scalardb-sql-cli -- java -jar /app.jar --config /conf/database.properties
    
  2. Create coordinator tables.
    CREATE COORDINATOR TABLES;
    
  3. Create namespaces.
    CREATE NAMESPACE schema0;
    
    CREATE NAMESPACE schema1;
    
  4. Create tables.
    CREATE TABLE schema0.t0 (
        c1 INT PRIMARY KEY,
        c2 INT,
        c3 TEXT
    );
    
    CREATE TABLE schema1.t1 (
        c1 INT PRIMARY KEY,
        c2 INT,
        c3 TEXT
    );
    
  5. INSERT records.
    INSERT INTO schema0.t0 VALUES (1, 11, 'A');
    
    INSERT INTO schema1.t1 VALUeS (2, 22, 'B');
    
    BEGIN;
    INSERT INTO schema0.t0 VALUES (3, 33, 'C');
    INSERT INTO schema1.t1 VALUeS (4, 44, 'D');
    COMMIT;
    
  6. SELECT all records.
    SELECT * FROM schema0.t0;
    
    SELECT * FROM schema1.t1;
    

Confirm the records in the backend DB (For testing only. Retrieving record from backend DB directly is NOT recommended in production environment.)

  1. SELECT records from MySQL (Backend DB 0).
    kubectl exec -it mysql-scalardb-0 -- mysql -u root -p schema0 -e "SELECT c1, c2, c3, tx_id FROM t0"
    
    • Password is mysql.
  2. SELECT records from PostgreSQL (Backend DB 1).
    kubectl exec -it postgresql-scalardb-0 -- psql -U postgres -c "SELECT c1, c2, c3, tx_id FROM schema1.t1"
    
    • Password is postgres.