Gradle Properties Yaml Plugin

The Properties plugin is a plugin heavily inspired by Gradle Properties Plugin, Grails 3 application.yml and Maven profiles.

Please note, that current implementation is more PoC than production-ready code.

See the CHANGELOG for recent changes.

Gradle way of loading and resolving properties is described in Gradle User Guide.

This plugin uses quite different concept both when it comes to property file format and order of processing. The order of execution for the properties plugin is (unlikely to Gradle original way), the first one wins:

0. The gradle.yml file in the current project's directory.
1. The gradle.yml file in the root project's directory, if the project is a module of a multi-project build.
2. The ${gradle.rootProject.name}.yml file in Gradle user home directory (usually ~/.gradle).
3. The gradle.yml file in Gradle user home directory.

Last but not least, some of the concepts are directly copied from original Gradle Properties Plugin. This is:

• A filterTokens thing - link
• requiredProperty and requiredProperties task extension - link

Custom YAML processing

Processing of YAML files is inspired by those in Grails 3 i.e.:

• All maps are flatten to regular properties
• Thanks to Spring's PropertyResolver properties are evaluated just like properties in Maven
• If YAML segment is marked as profile (profile.id) it will be included only if it is active (profile.active: true) or is activated from command-line (gradle -PyamlProfiles=fakehost)

Example

YAML file

---
nexus:
  base:
    username: '@env.USER@' #Environment variable
    password: pass1
  deploy:
    username: user2
    password: pass2
---
profile:
  id: localhost
  active: true

hibernate.connection:
    driverClass: 'com.mysql.jdbc.Driver'
    host: localhost
    port: 3306
    url: 'jdbc:mysql://@hibernate.connection.host@:@hibernate.connection.port@/database'
ldap:
  host: localhost
  port: 1389
  rootdn: 'cn=admin,dc=somecompany,dc=com'
  rootpw: pass3

systemProp:
  q: werty
  lorem: ipsum

---
profile:
  id: fakehost
hibernate.connection.host: fakehost

Gradle snippet

apply plugin: 'gradle-properties-yaml-plugin'

def undotKeys(key) {
  if (!key.contains('.')) { key += 'x' }
  key.replaceAll(/\.(\w)/) { match, group -> group.toUpperCase() }
}

task printProps << {
  project.ext.properties
    .sort { e1, e2 -> undotKeys(e1.key) <=> undotKeys(e2.key) }
    .each { k, v -> if (k != 'filterTokens') println "${k} :: ${v}" }
  println '\nChecking system properties\n'
  println System.getProperty('lorem', /'lorem'' does not exists as system property/)
  println System.getProperty('ldap.rootpw', /'ldap.rootpw' does not exists as system property/)
}

Gradle output (gradle printProps)

hibernate.connection.driverClass :: com.mysql.jdbc.Driver
hibernateConnectionDriverClass :: com.mysql.jdbc.Driver
hibernate.connection.host :: localhost
hibernateConnectionHost :: localhost
hibernate.connection.port :: 3306
hibernateConnectionPort :: 3306
hibernate.connection.url :: jdbc:mysql://localhost:3306/database
hibernateConnectionUrl :: jdbc:mysql://localhost:3306/database
ldap.host :: localhost
ldapHost :: localhost
ldap.port :: 1389
ldapPort :: 1389
ldap.rootdn :: cn=admin,dc=somecompany,dc=com
ldapRootdn :: cn=admin,dc=somecompany,dc=com
ldap.rootpw :: pass3
ldapRootpw :: pass3
lorem :: ipsum
nexus.base.password :: pass1
nexusBasePassword :: pass1
nexus.base.username :: mwiktorczyk
nexusBaseUsername :: mwiktorczyk
nexus.deploy.password :: pass2
nexusDeployPassword :: pass2
nexus.deploy.username :: user2
nexusDeployUsername :: user2
org.gradle.daemon :: true

Checking system properties

ipsum
'ldap.rootpw' does not exists as system property

Gradle output (gradle printProps -PyamlProfiles=fakehost)

hibernate.connection.driverClass :: com.mysql.jdbc.Driver
hibernateConnectionDriverClass :: com.mysql.jdbc.Driver
hibernate.connection.host :: fakehost
hibernateConnectionHost :: fakehost
hibernate.connection.port :: 3306
hibernateConnectionPort :: 3306
hibernate.connection.url :: jdbc:mysql://fakehost:3306/database
hibernateConnectionUrl :: jdbc:mysql://fakehost:3306/database
ldap.host :: localhost
ldapHost :: localhost
ldap.port :: 1389
ldapPort :: 1389
ldap.rootdn :: cn=admin,dc=somecompany,dc=com
ldapRootdn :: cn=admin,dc=somecompany,dc=com
ldap.rootpw :: pass3
ldapRootpw :: pass3
lorem :: ipsum
nexus.base.password :: pass1
nexusBasePassword :: pass1
nexus.base.username :: mwiktorczyk
nexusBaseUsername :: mwiktorczyk
nexus.deploy.password :: pass2
nexusDeployPassword :: pass2
nexus.deploy.username :: user2
nexusDeployUsername :: user2
org.gradle.daemon :: true
yaml.profiles :: fakehost
yamlProfiles :: fakehost

Checking system properties

ipsum
'ldap.rootpw' does not exists as system property

Gradle output (gradle printProps -PyamlProfiles=fakehost,!localhost)

hibernate.connection.host :: fakehost
hibernateConnectionHost :: fakehost
nexus.base.password :: pass1
nexusBasePassword :: pass1
nexus.base.username :: mwiktorczyk
nexusBaseUsername :: mwiktorczyk
nexus.deploy.password :: pass2
nexusDeployPassword :: pass2
nexus.deploy.username :: user2
nexusDeployUsername :: user2
org.gradle.daemon :: true
yaml.profiles :: fakehost,!localhost
yamlProfiles :: fakehost,!localhost

Checking system properties

'lorem'' does not exists as system property
'ldap.rootpw' does not exists as system property

Usage

To use the plugin with Gradle 2.1 or later, add the following to the build.gradle file:

plugins {
  id 'pl.softmate.gradle-properties-yaml-plugin' version '0.0.2'
}

To use the plugin with Gradle 2.0 or older, add the following to build.gradle:

// Pull the plugin from Bintray
buildscript {
  repositories {
    jcenter()
}
  dependencies {
    classpath 'pl.softmate:gradle-properties-yaml-plugin:0.0.2'
  }
}

// invoke the plugin
apply plugin: 'pl.softmate.gradle-properties-yaml-plugin'