App Level Gradle File

build.gradle

buildscript {
    fabric ...
}
apply plugin: 'com.android.application'
apply plugin: 'io.fabric'

repositories {
    maven { url 'https://maven.fabric.io/public' }
}

def keystoreProperties = new Properties()
def keystorePropertiesFile = rootProject.file('keys.properties')
def fabricKeyStoreFile = rootProject.file('fabric.properties')

if (keystorePropertiesFile.exists()) {
    println 'KeyFile Exists'
    keystoreProperties.load(new FileInputStream(keystorePropertiesFile))
} else {
    // Load keystore properties from environment or set their default values
    def env = System.getenv()
    if (env['KEYSTORE_ALIAS']) keystoreProperties.put('keyAlias', env['KEYSTORE_ALIAS'])
    else keystoreProperties.put('keyAlias', "myDefaultAlias")
    
    if (env['KEYSTORE_KEY_PASS']) keystoreProperties.put('keyPassword', env['KEYSTORE_KEY_PASS'])
    else keystoreProperties.put('keyPassword', "myDefaultKeyPass")
    
    if (env['KEYSTORE_HOME']) keystoreProperties.put('storeFile', env['KEYSTORE_HOME'])
    else keystoreProperties.put('storeFile', "${project.projectDir.absolutePath}/keystore.jks")
    
    if (env['KEYSTORE_KEY_PASS']) keystoreProperties.put('storePassword', env['KEYSTORE_STORE_PASS'])
    else keystoreProperties.put('storePassword', "myDefaultStorePass")
    
    if (env['FABRIC_KEY']) keystoreProperties.put('fabric_api_key', env['FABRIC_KEY'])
    else keystoreProperties.put('fabric_api_key', "myDefCrashlyticsApiKey")
    
    if (env['FABRIC_SECRET']) keystoreProperties.put('fabric_apiSecret', env['FABRIC_SECRET'])
    else keystoreProperties.put('fabric_apiSecret', "myDefCrashlyticsApiKey")
}

if (!fabricKeyStoreFile.exists()) {
    fabricKeyStoreFile = new File("${project.projectDir.absolutePath}/fabric.properties")
    Properties properties = new Properties()
    properties.put("apiSecret", keystoreProperties['fabric_apiSecret'])
    properties.put("apiKey", keystoreProperties['fabric_api_key'])
    properties.store(new FileWriter(fabricKeyStoreFile), "")
}

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.2"

    defaultConfig {
        applicationId "someapplication"
        minSdkVersion 15
        targetSdkVersion 25
        versionCode 1
        versionName "1.0.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }

    testOptions {
        unitTests.returnDefaultValues = true
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.2.0'
    testCompile 'junit:junit:4.12'
    testCompile 'org.mockito:mockito-core:1.10.19'
    compile('com.crashlytics.sdk.android:crashlytics:2.6.6@aar') {
        transitive = true;
    }
}