ha

Highly available SQLite cluster

Powered by an embedded NATS JetStream server.

Features

• 🔌 Connect using HTTP API, gRPC API, database/sql go driver, JDBC driver, MySQL or PostgreSQL Wire Protocol
• 🔁 Replicate data using embedded or external NATS server
• 📝 Create live local read/write replicas with go-ha database/sql driver
• 📚 Create live local read replicas with ha-sync SQLite extension
• 🔄 Supports Change Data Capture (CDC)
• ⚙️ Configure a leader-based or leaderless cluster (with custom strategies for resolving replication data conflicts)
• 📚 Execute cross-shard queries using SQL hint /*+ db=DSN */ (where DSN is a regexp to DataSource name)
• 📖 Full documentation: https://litesql.github.io/ha/

🚀 Getting Started

Download and install the latest release

1. Start the first ha instance

mkdir db1
ha -n node1 --pg-port 5432 --mysql-port 3306 "file:db1/mydatabase.db"

This command launches:

• An embedded NATS server on port 4222
• A MySQL Wire Protocol compatible server on port 3306
• A PostgreSQL Wire Protocol compatible server on port 5432
• An HTTP API server on port 8080

2. Start a second ha instance

mkdir db2
ha -n node2 --nats-port 0 -p 8081 --pg-port 5433 --mysql-port 3307 --replication-url nats://localhost:4222 "file:db2/mydatabase.db"

This command starts:

• A PostgreSQL Wire Protocol server on port 5433
• A MySQL Wire Protocol server on port 3307
• An HTTP API server on port 8081.

It connects to the previously launched embedded NATS server for replication.

3. Connect using a client

Special HA Client commands:

Command	Description
SHOW DATABASES;	List all databases
CREATE DATABASE ;	Create a new database
DROP DATABASE ;	Drop a database
SET DATABASE TO ;	Send commands to a specific database
UNSET DATABASE;	Use default database
EXIT;	Quit client (ctrl+d)

3.1 HA Client

ha -r http://localhost:8080

3.2. PostgreSQL Client

PGPASSWORD=ha psql -h localhost -U ha

3.3 MySQL Client

mysql -h localhost --port 3306 -u ha

Create and populate a table:

CREATE TABLE users(ID INTEGER PRIMARY KEY, name TEXT);
INSERT INTO users(name) VALUES('HA user');

4. Verify replication on the second instance

ha -r http://localhost:8081

Using postgresql client:

PGPASSWORD=ha psql -h localhost -U ha -p 5433

SELECT * FROM users;
 ID |  name   
----+---------
 1  | HA user

Using a mysql client:

mysql -h localhost --port 3307 -u ha

MySQL [(none)]> show databases;
+---------------+
| Database      |
+---------------+
| mydatabase.db |
+---------------+
1 row in set (0,000 sec)

MySQL [(none)]> use mydatabase.db

MySQL [mydatabase.db]> select * from users;
+----+---------+
| ID | name    |
+----+---------+
|  1 | HA user |
+----+---------+
1 row in set (0,000 sec)

5. Please refer to the complete documentation for the HTTP API

HTTP API

🛠️ License & Contributions

This project is open-source. Contributions, issues, and feature requests are welcome via GitHub.