Using Liquibase with Cassandra on DataStax Astra

DataStax Astra is a multi-cloud DBaaS built on Apache Cassandra. Astra simplifies cloud-native Cassandra application development and reduces deployment time from weeks to minutes. For more information, see DataStax AstraDB Documentation.

Supported versions

4.X
3.11.X

Prerequisites

Introduction to Liquibase – Dive into Liquibase concepts.
Install Liquibase – Download Liquibase on your machine.
Get Started with Liquibase – Learn how to use Liquibase with an example database.
Design Your Liquibase Project – Create a new Liquibase project folder and organize your changelogs
How to Apply Your Liquibase Pro License Key – If you use Liquibase Pro, activate your license.

Install drivers

To use Liquibase and Cassandra on DataStax Astra, you need two JAR files: a JDBC driver and the Liquibase Cassandra extension:

Download the Simba JDBC driver JAR file and select Simba JDBC Driver for Apache Cassandra from the dropdown menu. Select the default package option unless you need a specific package. The driver downloads as a ZIP file named SimbaCassandraJDBC42-x.x.x.zip.
Extract the CassandraJDBCxx.jar file and place it in the liquibase/lib directory.
Open the Liquibase properties file and specify the driver, as follows:

driver: com.simba.cassandra.jdbc42.Driver

Go to the liquibase-cassandra repository and download the latest released Liquibase extension JAR file: liquibase-cassandra-version.jar.

Place your JAR file(s) in the liquibase/lib directory.

If you use Maven, note that this database does not provide its driver JAR on a public Maven repository, so you must install a local copy and add it as a dependency to your pom.xml file.

<dependency>
    <groupId>com.datastax.jdbc</groupId>
    <artifactId>CassandraJDBC42</artifactId>
    <version>4.2</version>
    <scope>system</scope>
    <systemPath>${basedir}/lib/CassandraJDBC42.jar</systemPath>
</dependency>
<dependency>
    <groupId>org.liquibase.ext</groupId>
    <artifactId>liquibase-cassandra</artifactId>
    <version>4.20.0</version>
</dependency>

You need to specify that the scope is system and provide the systemPath in pom.xml. In the example, the ${basedir}/lib is the location of the driver JAR file.

Test your connection

Ensure your Cassandra on DataStax Astra database is configured:
1. Log into your DataStax Astra account. From Dashboard, select the needed database, and then go to the Connect tab. Under Connect using an API, select Java and download the Connect Bundle by following the link in step 1 under Prerequisites.
2. Once the secure-connect-<dbname>.zip file is fully downloaded, place it in a secure place in your file system.
3. Unzip the secure-connect-<dbname>.zip file. Open the config.json file in a text editor. We will use the information from the file in the next step.
4. Clone the cql-proxy repository to set up CQL-Proxy, which is a sidecar that enables unsupported CQL drivers to work with DataStax Astra.
  1. You need your Astra Token and Astra Database ID to use CQL-Proxy.
  2. Follow the steps in the repository to spin up CQL-Proxy using your command prompt. Once successfully running, you should see the following output:
Specify the database URL in the liquibase.properties file (defaults file), along with other properties you want to set a default value for. Liquibase does not parse the URL. You can either specify the full database connection string or specify the URL using your database's standard JDBC format:
```
url: jdbc:cassandra://localhost:9042/test;DefaultKeyspace=test;TunableConsistency=6
```
Replace test with your own keyspace name.

Tip: To apply a Liquibase Pro key to your project, add the following property to the Liquibase properties file: licenseKey: <paste code here>

Create a text file called changelog (.xml, .sql, .json, or .yaml) in your project directory and add a changeset.

If you already created a changelog using the init project command, you can use that instead of creating a new file. When adding onto an existing changelog, be sure to only add the changeset and to not duplicate the changelog header.

XML example

<?xml version="1.0" encoding="UTF-8"?>
<databaseChangeLog
    xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
    xmlns:pro="http://www.liquibase.org/xml/ns/pro"
    xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
        http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd
        http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd
        http://www.liquibase.org/xml/ns/pro http://www.liquibase.org/xml/ns/pro/liquibase-pro-latest.xsd">

    <changeSet id="1" author="Liquibase">
        <createTable tableName="test_table">
            <column name="test_id" type="int">
                <constraints primaryKey="true"/>
            </column>
            <column name="test_column" type="varchar"/>
        </createTable>
    </changeSet>

</databaseChangeLog>

SQL example

-- liquibase formatted sql

-- changeset liquibase:1
CREATE TABLE test_table (test_id INT, test_column VARCHAR(255), PRIMARY KEY (test_id))

Tip: Formatted SQL changelogs generated from Liquibase versions before 4.2 might cause issues because of the lack of space after a double dash ( -- ). To fix this, add a space after the double dash. For example: -- liquibase formatted sql instead of --liquibase formatted sql and -- changeset myname:create-table instead of --changeset myname:create-table.

YAML example

databaseChangeLog:
   - changeSet:
       id: 1
       author: Liquibase
       changes:
       - createTable:
           tableName: test_table
           columns:
           - column:
               name: test_column
               type: INT
               constraints:
                   primaryKey:  true
                   nullable:  false

JSON example

{
  "databaseChangeLog": [
    {
      "changeSet": {
        "id": "1",
        "author": "Liquibase",
        "changes": [
          {
            "createTable": {
              "tableName": "test_table",
              "columns": [
                {
                  "column": {
                    "name": "test_column",
                    "type": "INT",
                    "constraints": {
                      "primaryKey": true,
                      "nullable": false
                    }
                  }
                }
              ]
            }
          }
        ]
      }
    }
  ]
}

Navigate to your project folder in the CLI and run the Liquibase status command to see whether the connection is successful:

liquibase status --username=test --password=test --changelog-file=<changelog.xml>

Note: You can specify arguments in the CLI or keep them in the Liquibase properties file.

If your connection is successful, you'll see a message like this:

4 changesets have not been applied to <your_jdbc_url>
Liquibase command 'status' was executed successfully.

Inspect the SQL with the update-sql command. Then make changes to your database with the update command.

liquibase update-sql --changelog-file=<changelog.xml>
liquibase update --changelog-file=<changelog.xml>

If your update is successful, Liquibase runs each changeset and displays a summary message ending with:

Liquibase: Update has been successful.
Liquibase command 'update' was executed successfully.

From a database UI tool, ensure that your database contains the test_table you added along with the DATABASECHANGELOG table and DATABASECHANGELOGLOCK table.

Now you're ready to start making deployments with Liquibase!