SmartPropertiesPlugin

SmartPropertiesPlugin allow handling build parameters in a simpler way, removing some boiler plate code in gradle files. It allows the project to:

add a string entry in BuildConfig.java
add a resource string to gradleResValues.xml
override these values with an environment variables
have variant specific set of values

Usage Example

Here is a sample file smart.properties in the root folder of our project:

property01.BuildConfig=prop01
property02.Resources=prop02
property03.Resources.BuildConfig=prop03

The smart.property file has the same structure as any *.property file: typically it's composed by pair key=value or a #commented out line or an empty line. Keys have the usual camelCase naming convention followed by some extra tokens:

the .BuildConfig token will generate a BuildConfig entry
the .Resources token will generate a string resource entry

Given the file above, the plugin modifies the BuildConfig.java file adding these lines:

public final class BuildConfig {
  //[...]
  public static final String PROPERTY_01 = "prop01";
  public static final String PROPERTY_03 = "prop03";
  //[...]
}

Please note the properties (key without any token) will be renamed to accommodate the BuildConfig.java naming convention. This can be avoided using the dontRenameProperties = true setting.

BuildConfig.java file can usually be found at the following location - although depending on the setup this might be different.

<root project folder>/<android app module>/build/generated/source/buildConfig/<variant>/<build type>/<package folders>/BuildConfig.java

Also, the plugin makes available these resource strings:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- [...] -->
    <string name="property_02" translatable="false">"prop02"</string>
    <string name="property_03" translatable="false">"prop03"</string>
    <!-- [...] -->
</resources>

Please note the properties (key without any token) will be renamed to accommodate XML resources naming convention. This can be avoided using the dontRenameProperties = true setting.

gradleResValues.xml file can usually be found at the following location - although depending on the setup this might be different.

<root project folder>/<android app module>/build/generated/res/resValues/<variant>/<build type>/values/gradleResValues.xml

Additionally, any of the above property values can be easily overridden by defining two types of environment variables:

(propertyName)=(new value) - this can simply be defined on any machine
(prefix_propertyName)=(new value) - same as above, the prefix is a general parameter, this is typically used on CI integration

Setting up appropriately prefix, the property can be overridden on a local machines or in a CI context - or both - in a flexible way.

Please note: the prefixed variable always has a higher priority.

So if we define a variable:

$ export property03=newvalue

the newvalue value will replace prop03 in both BuildConfig.java and XML resources.

If we define:

$ export property03=newvalue
$ export prefix_property03=latestvalue

Then latestvalue will be the value used instead.

Please note the env var prefix needs to be set using the option ciEnvironmentPrefix=prefix_

Setup

Add the plugin to your root project using the new plugin DSL:

plugins {
  id "com.guidovezzoni.smartproperties" version "<latest version>"
}

or the legacy plugin application:

buildscript {
  repositories {
    maven {
      url "https://plugins.gradle.org/m2/"
    }
  }
  dependencies {
    classpath "gradle.plugin.com.guidovezzoni.smartproperties:smart-properties:<latest version>"
  }
}

Load the plugin in your app subproject and configure it

apply plugin: 'com.guidovezzoni.smartproperties'

PLEASE NOTE: This plugin is meant to be used in a gradle Android sub-project, it hasn't been tested in a different configuration.

Configuration

Here are the available settings:

smartPropertiesPlugin {
    defaultConfig {
        sourceFile = file("$rootDir/smart.properties")
        ciEnvironmentPrefix = "build_"
        dontRenameProperties = true
    }

    productFlavors {
        alpha {
            sourceFile = file("$rootDir/smartprop-alpha.properties")
        }
        beta {
            sourceFile = file("$rootDir/smartprop-beta.properties")
        }
        prod {
            ciEnvironmentPrefix = "prod_"
        }
    }
}

Available settings:

Name	Description	Default Value	Notes
sourceFile	java file pointing at the location of the `*.properties` file	`file("$rootDir/smart.properties")`
ciEnvironmentPrefix	prefix used to check env variable values	`""` (empty string)
dontRenameProperties	if `true` prevent the property name to be adapted to the host file naming convention.	false	This can be helpful in case of issues or conflicts with resources naming

Known Issues

Generated resValue resources do not seem to be identified correctly by AndroidStudio IDE, however they are built correctly by both gradle and AndroidStudio

Enhancement List

Major features

~~environment variables~~
support gradle ext - investigation in progress
~~support flavours~~
fabric https://github.com/plastiv/CrashlyticsDemo/

Minor features/tech improvements

~~logger~~
~~unit test https://guides.gradle.org/testing-gradle-plugins/~~
~~uppercase/underscores for buildconfig~~

Version History

Latest version: 0.5.0-beta

Version	Date	Issues	Notes
0.5.1-beta	04/05/2020	004 (updated dontRenameProperties)
0.5.0-beta	29/04/2020	003 (additional unit tests), 004 (dontRenameProperty)
0.4.0_beta	16/04/2020	flavors support, logger, unit test
0.3.0_beta	28/03/2020	env var support, Project renamed
0.2.0_beta	15/03/2020		First beta release

Licence

   Copyright 2020 Guido Vezzoni

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

guidovezzoni/smart-properties