property-helper Maven Plugin

Define, create and manipulate properties for the maven build cycle. This plugin can

create properties to e.g. represent build versions, identifiers, switches etc.
combine different type of fields into properties and export them to the maven build cycle
manipulate existing properties

The plugin has two goals:

property-helper:get - load and save property files, define fields, combine fields to property groups and new properties, export these to the maven build
property-helper:inc - increment number field values by loading, manipulating and saving property files

Configuration

The plugin defines different fields that are combined to form properties:

string fields - provides a string field
number fields - provide a structured number field
date fields - provide a formatted date field
uuid fields - provide a uuid value field
macro fields - custom code to provide specific fields

Each field can be exported directly as a build property or combined to form a property group which then is exported as a build property.

A property group can be activated for release or snapshot builds and aggregates fields into a single property that gets exposed.

Reproducible builds are supported if the ${project.build.outputTimestamp} is set.

Maven plugin configuration example

<configuration>
    <propertyGroups>
        <propertyGroup>
            <id>build-tag</id>
            <properties>
                <property>
                    <name>build.tag</name>
                    <value>@{build-tag}-@{build-number}-@{build-date}</value>
                </property>
            </properties>
        </propertyGroup>
    </propertyGroups>
    <dates>
        <date>
            <id>build-date</id>
            <timezone>UTC</timezone>
            <format>yyyyMMdd_HHmmss</format>
        </date>
    </dates>
    <uuids>
        <uuid>
            <id>build-tag</id>
        </uuid>
    </uuids>
    <numbers>
        <number>
            <id>build-number</id>
            <propertyNameInFile>build.number</propertyNameInFile>
            <propertyFile>${user.home}/build.properties</propertyFile>
            <onMissingFile>create</onMissingFile>
            <onMissingFileProperty>create</onMissingFileProperty>
            <initialValue>1</initialValue>
        </number>
    </numbers>
</configuration>

This configuration defines three fields, build-date, build-tag and build-number. They are combined to form a property build.tag which can be referred to in following build steps as ${build.tag}.

The build-date field is a date field. As there is no value given or loaded from a file, it uses the current time as its value. By setting the timezone to UTC, this timezone will be used.

build-tag is a UUID value. As no seed value is given and the field is also not loaded from a file, it creates a random UUID.

Finally, build-number is a number field. It is backed by a property in a property file build.properties (which e.g. lives in the home directory of the CI user). Its value is loaded from the build.number property in the file (and if the file or the property do not exist, it will create those).

All three values combined form the build.tag property which is exported as a property.