dropwizard-dbdeploy

Embedded dbdeploy for dropwizard

This project provides a command for dropwizard that will run an embedded version of dbdeploy. This has the benefit over dropwizard-migrations in that it uses sql deltas rather than liquibase xml change definitions. For an introduction to dbdeploy see here.

Whilst dbdeploy only allows for its deltas to be available on the file system, this project uses the reflections library, which allows script files to be located inside the main application jar. This means you can provide joint application and database releases in one archive.

A "run" command is also provided, which allows you to run arbitrary scripts that are present in the classpath.

N.B This is also an easy way to provide a database release as a standalone java application - you don't neccessarily have to use dropwizard as you stack for you application.

Example project

An example project can be found here

Example Yaml File

database:  
    
    driverClass : com.mysql.jdbc.Driver
    user        : root
    password    : 
    url         : jdbc:mysql://localhost:3306/demando

    dbdeploy:
       scriptLocation    : db/scripts/deltas/
 

Example Usage

echo "##########################";
echo "Recreating database!";
echo "##########################";
java -jar dropwizard-dbdeploy-sample-0.0.1-SNAPSHOT.jar db run -s scripts/drop.sql sample.create.yaml

echo "##########################";
echo "Creating changelog table!";
echo "##########################";
java -jar dropwizard-dbdeploy-sample-0.0.1-SNAPSHOT.jar db run -s scripts/createSchemaVersionTable.mysql.sql sample.yaml

echo "##########################";
echo "running upgrade";
echo "##########################";
java -jar dropwizard-dbdeploy-sample-0.0.1-SNAPSHOT.jar db upgrade sample.yaml

Integrating with dbdeploy

dropwizard-dbdeploy is available in the central maven repo:

<dependency>
  <groupId>uk.co.optimisticpanda</groupId>
  <artifactId>dropwizard-dbdeploy</artifactId>
  <version>0.0.1</version>
</dependency>

To add to a dropwizard application, you just need to use the DbDeployDatabaseConfiguration object rather than the DatabaseConfiguration Object. (This extends the DatabaseConfiguration Object, so it's still possible to use dropwizard-jdbi and dropwizard-hibernate):

public class AutoUpgradeDbSampleService extends Service<SampleConfiguration> {
    @Override
    public void initialize(Bootstrap<SampleConfiguration> bootstrap) {
        bootstrap.addBundle(new DbDeployBundle<SampleConfiguration>() {
            public DbDeployDatabaseConfiguration getDatabaseConfiguration(SampleConfiguration configuration) {
                return configuration.getDatabaseConfiguration();
            }
        });
    }
    ...
}

Chaining Database Upgrade and Application Startup

You can easily create a main class, that chains the server and upgrade commands, which will automatically run upgrades on application startup:

public static void main(String[] args) throws Exception {
        new AutoUpgradeDbSampleService().run(new String[]
                {"db", "upgrade", "sample.yaml"});
        new AutoUpgradeDbSampleService().run(new String[]
                { "server", "sample.yaml"});
    }

Full dbdeploy Options:

Most options have defaults as described below. The only mandatory option is scriptLocation.

database:
    # Supports all of the standard dropwizard database parameters
    driverClass: com.mysql.jdbc.Driver
    user       : root
    password   : 
    url        : jdbc:mysql://localhost:3306/demando
         
    # Configures the dbdeploy instance
    dbdeploy:

       # The location of the classpath folder that contains all of the deltas 
       scriptLocation : scripts/deltas/

       # The name of the dbms. Possible options include: db2, hsql, mssql, mysql, ora, syb-ase 
       dbms           : mysql

       # The delimiter between statements, defaults to ';' 
       delimiter      : ;

       # The type of delimiter 'normal' (delimiter can appear anywhere) or 'row' (must be on a row on its own), defaults to 'normal' 
       delimiterType  : normal
       
       # The encoding present in the script/delta files, defaults to 'UTF-8' 
       encoding       : UTF-8
   
       # The number of the last delta to apply. This is optional with no default
       lastChangeToApply : 099

       # The style of line ending present in the script/delta files. Possible options include : platform, cr, crlf, lf. Defaults to platform line seperator.
       lineEnding : platform
 
       # Specifying this file means that instead of applying the delta to the database, it generates one script with all of the applicable deltas.
       outputFile : output.sql
   
       # Overide the default undo and apply script templates. This points to somewhere on the classpath. This is optional and defaults to the standard templates located inside dbdeploy. 
       templatesLocation : db/templates

       # Specifying this file will generate an undo file in this specific location. This is optional
       undoOutputFile : undoOutput.sql