Working with Kapua database
In current implementation of Kapua we hold device data in SQL database (it can MariaDB or H2 SQL Server). In order to keep SQL schema updated, we decided to use Liquibase.
Liquibase in Kapua
Kapua broker on startup executes embedded Liquibase client which ensures that all database update scripts have been collected and applied to your database. The coordinates of database URL connection are obtained from regular Kapua settings i.e. the following system properties:
Liquibase clients looks up for all scripts located in the classpath matching
Adding new SQL script to the project
If you would like a new SQL script to your service, just add new
*.sql file to
src/main/resources/liquibase directory of your Maven project. Just keep in mind that
the name of your file should be unique, so the best way is to make it matching the name of your service module (for example
device.sql for device management).
Adding a new change set to existing SQL file
If you would like to add new change set to existing SQL file, append new
--changeset filename:number line to your log file. The example:
--changeset device_event:2 CREATE TABLE my_new_table ( scope_id BIGINT(21) UNSIGNED NOT NULL PRIMARY KEY (scope_id, id) ) CHARSET=utf8;
More details regarding Liquibase SQL file syntax, can be found on Liquibase web page.