Groovy Liquibase

A pluggable parser for Liquibase that allows the creation of changelogs in a Groovy DSL, rather than hurtful XML. If this DSL isn't reason enough to adopt Liquibase, then there is no hope for you. This project was started once upon a time by Tim Berglund, and is currently maintained by Steve Saliman.

Version 4.0.0 has finally been released!

After far too long, release 4.0.0 has been released adding support for Liquibase 4.26+. See the News section for more details.

Important note for Groovy 4 and build tools: This DSL is built with a transitive dependency on Groovy 3.0.15. This ensures that Gradle and Maven users don't need to include Groovy in the classpath for the DSL to work, but because Groovy moved into the Apache foundation for version 4, and changed the artifact group, users who want to use Groovy 4 need to exclude the transitive dependency. Here is an example of how users of the Liquibase Gradle plugin can do it:

liquibaseRuntime('org.liquibase:liquibase-groovy-dsl:4.0.0') {
    exclude group: "org.codehaus.groovy", module: "groovy"
    exclude group: "org.codehaus.groovy", module: "groovy-sql"
  }
liquibaseRuntime "org.apache.groovy:groovy:4.0.5"
liquibaseRuntime "org.apache.groovy:groovy-sql:4.0.5"

News

March 12, 2024

Release 4.0.0 adds support for Liquibase 4.26, and removed official support for versions prior to that. Liquibase has had a lot of internal API changes between 6.16.1 and 4.26, and the plugin will most likely not work with older versions.

This release has breaking changes

• The new version removes support for absolute paths. Liquibase hasn't supported them in a long time, so the Groovy DSL no longer does either. If, for some reason, you are using absolute paths in an include or includeAll, they will need to be fixed, and you will most likely need to fix the entries in the databasechangelog table as well.

• The Groovy DSL used to "fix" the path of files that were included relative to the changelog. All paths are now going to be relative to the working directory, which is how the other Liquibase parsers work. This means that if you are using relativeToChangeLog in any of your include or includeAll methods, you'll have to fix the paths in the databasechangelog table to be relative to the working directory instead of the changelog.

• The Groovy DSL used to have a default filter for includeAll. None of the other parsers did this so we no longer do. If you are doing an includeAll on a directory that has more than just the groovy files you want to include, this will be a breaking change. Adding endsWithFilter: ".groovy" to the includeAll will fix this issue.

• The groovy DSL removed support for the deprecated onUpdateSQL precondition attribute. Use onUpdateSql instead.

In addition, the Groovy DSL doesn't support the Liquibase PRO modifyChangeSets change.

March 12, 2023

Release 3.0.3 adds support for Liquibase up to version 4.16.1, and it adds support for Groovy 4 (#53), with thanks to Bjørn Vester (@bjornvester)

June 12, 2021

Release 3.0.2 Fixes a bug with change log parameters (#50)

April 16, 2021

Version 3.0.1 of the Liquibase Groovy DSL is now available with support for Liquibase 4.2.2.

September 5, 2020

Version 3.0.0 of the Liquibase Groovy DSL is now available with support for Liquibase 4.0.0.

As you might expect for a major release, this means some breaking changes. There are two breaking changes with this release.

Version 3.0.0 of the DSL no longer supports the 3.x releases of Liquibase. If you need to use an older version of Liquibase, you'll need an older version of the DSL.

Liquibase 4.0.0 no longer supports using absolute filenemes, so the DSL doesn't either. This change only affects changelogs that were using the include and includeAll elements with absolute paths.

June 6, 2020

Release 2.1.2 is a minor release that fixes an issue with include and includeAll changes nested inside change logs that used the previously added logicalFilePath support.

January 25, 2020

Added support for an undocumented ChangeSet attribute. The XML accepts an attribute named logicalFilePath. The actual ChangeSet property in the source code is named filePath. The Groovy DSL now supports both. The default is still to inherit the filePath from the DatabaseChangeLog. This resolves Issue #45. The bugs in Liquibase 3.7+ still remain as of Liquibase 3.8.5, so use those versions with care.

Usage

Simply include this project's jar file in your class path, along with a version of Liquibase, a version of Groovy, and your database driver, and Liquibase can parse elegant Groovy changelogs instead of ugly XML ones.

If you are running Liquibase directly from the command line using the binary distribution of Liquibase, you would need to copy the liquibase-groovy-dsl, groovy-x.y.z and database driver jar files into the internal/lib directory of the Liquibase distribution. If you are running Liquibase using a Gradle plugin, Maven plugin, or Spring Boot, follow the documentation of the tool to add these artifacts to the classpath.

The DSL syntax is intended to mirror the Liquibase XML syntax directly, such that mapping elements and attributes from the Liquibase documentation to Groovy builder syntax will result in a valid changelog. Hence, this DSL is not documented separately from the Liquibase XML format. We will, however let you know about the minor differences or enhancements to the XML format, and help out with a couple of the holes in Liquibase's documentation of the XML format.

Note that wile the Groovy DSL fully supports using absolute paths for changelogs, we strongly recommend using relative paths instead. When Liquibase sees an absolute path for a changelog, all changes included by that changelog will also have absolute path names, even if the include or includeAll element used the relativeToChangeLog attribute. This will cause problems in multi-developer environments because the difference in the users' directories will cause Liquibase to think that the changes are new, and it will try to run them again.

Deprecated and Unsupported Items

• The Liquibase includeAll element has minDepth and maxDepth attributes, but they are broken in Liquibase itself (liquibase/liquibase#5654). The Groovy DSL will pass them to Liquibase as-is, so once this is fixed in Liquibase, they will work in the Groovy DSL as well.

• The Groovy DSL doesn't support the modifyChangeSets change.

• Liquibase has a whereParam element for changes like the update change. It isn't documented in the Liquibase documentation, and I don't see any benefits of using it over the simpler where element, so it has been left out of the Groovy DSL.

• The documentation mentions a deprecated referencesUniqueColumn attribute of the addForeignKeyConstraint change, but what it doesn't tell you is that it is ignored. Since Liquibase deprecated it, the Groovy DSL does as well, and it will print a warning message.

• Prior to 2.0.0, the DSL used the resourceFilter attribute of the includeAll element to filter the changelogs included in a directory. This has been changed to filter to remain consistent with Liquibase itself.

Additions to the XML format:

• Sometimes, you may want to include all SQL files in a given directory. For example, you may have the source for all your stored procedures in a directory, and you want to reload each file whenever that file changes. The Groovy DSL adds an includeAllSql element to databaseChangeLog to do this. It combines the functionality if includeAll and sqlFile in one convenient element. includeAllSql creates a changeSet for each file it finds in a given directory. Each changeSet will contain a single sqlFile change that will rerun whenever the file itself changes. The id of each generated changeSet will be derived from the name of the SQL file the changeSet runs. The includeAllSql element takes a map of attributes that include the valid parameters from includeAll, changeSet, and sqlFile, with a few exceptions:

  • Since changeSet ids are generated, id attribute is not supported by includeAllSql
  • The author attribute is supported, but optional. Different SQL files could have different authors, so the default is "various (generated by includeAllSql)".
  • The intent of includeAllSql is to "monitor" the files in the included directory for changes, so the default value for runOnChange is true.
  • The filePath, logicalFilePath, runInTransaction, and runOrder attributes are not supported by includeAllSql because it creates multiple changeSets, and it doesn't make much sense to run a SQL file outside a transaction.
  • The idPrefix, idSuffix, and idKeepsExtension attributes are specific to includeAllSql, and control how the changeSet ids are generated. By default, the id is simply the name of the SQL file, minus the directory and extension. idPrefix and idSuffix allow you to prepend or append text to that name, and idKeepsExtension lets you include the file's extension in the id.

• In general, boolean attributes can be specified as either strings or booleans. For example, changeSet(runAlways: 'true') can also be written as changeSet(runAlways: true).

• The Groovy DSL supports a simplified means of passing arguments to the executeCommand change. Instead of:

execute {
  arg(value: 'somevalue')
}

You can use this the simpler form:

execute {
  arg 'somevalue'
}

• The sql change does not require a closure for the actual SQL. You can just pass the string like this: sql 'select some_stuff from some_table'. If you want to use the comments element of a sql change, you need to use the closure form, and the comment must be in the closure BEFORE the SQL, like this:

sql {
  comment('we should not have added this...')
  'delete from my_table'
}

• The stop change can take a message as an argument as well as an attribute. In other words, stop 'message' works as well as the more XMLish stop(message: 'message')

• A customPrecondition can take parameters. the XMLish way to pass them is with param(name: 'myParam', value: 'myValue') statements in the customPrecondition's closure. In the Groovy DSL, you can also have myParam('myValue')

• The validChecksum element of a change set is not well documented. Basically you can use this when changeSet's current checksum will not match what is stored in the database. This might happen if you, for example want to reformat a changeSet to add white space. This doesn't change the functionality of the changeset, but it will cause Liquibase to generate new checksums for it. The validateChecksum element tells Liquibase to consider the checksums in the validChecksum element to be valid, even if it doesn't match what is in the database.

• The Liquibase documentation tells you how to set a property for a databaseChangeLog by using the property element. What it doesn't tell you is that you can also set properties by loading a property file. To do this, you can have property(file: 'my_file.properties') in the closure for the databaseChangeLog.

• Liquibase has an includeAll element in the databaseChangeLog that includes all the files in the given directory. The Groovy DSL implementation makes sure they are included in alphabetical order by path, like Liquibase itself does. This is really handy for keeping changes in a different file for each release. As long as the file names are named with the release numbers in mind, Liquibase will apply changes in the correct order.

• Remember, the Groovy DSL is basically just Groovy closures, so you can use groovy code to do things you could never do in XML, such as this:

sql { """
  insert into some_table(data_column, date_inserted)
  values('some_data', '${new Date().toString()}')
"""
}

Items that were left out of the XML documentation

• The column element has some undocumented attributes. valueSequenceNext, valueSequenceCurrent, and defaultValueSequenceNext, which appear to link values for a column to database sequences.

• Liquibase added the context attribute to the include, includeAll, and changeLog elements. They work the same as the context attribute of a change set.

• The Liquibase XML accepts a logicalFilePath attribute for the changeSet element. The actual property in the ChangeSet class is named filePath. The Groovy DSL accepts both. The default is to inherit the file path from the DatabaseChangeLog that contains the ChangeSet.

License

This code is released under the Apache Public License 2.0, just like Liquibase itself.

TODOs

• Support for the customChange. Using groovy code, liquibase changes and database SQL in a changeSet.
• Support for extensions. modifyColumn is probably a good place to start.