Secrets Gradle plugin

Google strongly recommends that you not check an API key into your version control system. Instead, you should store it in a local secrets.properties file, which is located in the root directory of your project but excluded from version control, and then use the Secrets Gradle Plugin for Android to read the API key.

The Secrets Gradle Plugin for Android reads secrets, including the API key, from a properties file not checked into a version control system. The plugin then exposes those properties as variables in the Gradle-generated BuildConfig class and in the Android manifest file.

For a complete example of using the Secrets Gradle Plugin for Android to access an API key, see Set up an Android Studio project.

Installation and usage

To install the Secrets Gradle Plugin for Android in your Google Maps project:

  1. In Android Studio, open your top-level build.gradle.kts or build.gradle file and add the following code to the dependencies element under buildscript.

    Kotlin

    buildscript {
    dependencies {
        classpath("com.google.android.libraries.mapsplatform.secrets-gradle-plugin:secrets-gradle-plugin:2.0.1")
    }
}

    Groovy

    buildscript {
    dependencies {
        classpath "com.google.android.libraries.mapsplatform.secrets-gradle-plugin:secrets-gradle-plugin:2.0.1"
    }
}
  2. Open your module-level build.gradle.kts or build.gradle file and add the following code to the plugins element.

    Kotlin

    plugins {
    // ...
    id("com.google.android.libraries.mapsplatform.secrets-gradle-plugin")
}

    Groovy

    plugins {
    // ...
    id 'com.google.android.libraries.mapsplatform.secrets-gradle-plugin'
}
  3. In your module-level build.gradle.kts or build.gradle file, ensure that targetSdk and compileSdk are set to 34.
  4. Sync your project with Gradle.
  5. Open the secrets.properties file in your top-level directory, and then add the following code. Replace YOUR_API_KEY with your API key. Store your key in this file because secrets.properties is excluded from being checked into a version control system. 
    MAPS_API_KEY=YOUR_API_KEY

  6. Create the local.defaults.properties file in your top-level directory, the same folder as the secrets.properties file, and then add the following code.

    MAPS_API_KEY=DEFAULT_API_KEY

    The purpose of this file is to provide a backup location for the API key if the secrets.properties file is not found so that builds don't fail. This can happen if you clone the app from a version control system which omits secrets.properties and you have not yet created a secrets.properties file locally to provide your API key.

  7. In your AndroidManifest.xml file, go to com.google.android.geo.API_KEY and update the android:value attribute. If the <meta-data> tag does not exist, create it as a child of the <application> tag. 
    <meta-data
    android:name="com.google.android.geo.API_KEY"
    android:value="${MAPS_API_KEY}" />

    Note: com.google.android.geo.API_KEY is the recommended metadata name for the API key. A key with this name can be used to authenticate to multiple Google Maps-based APIs on the Android platform, including the Maps SDK for Android. For backwards compatibility, the API also supports the name com.google.android.maps.v2.API_KEY. This legacy name allows authentication to the Android Maps API v2 only. An application can specify only one of the API key metadata names. If both are specified, the API throws an exception.

  8. In Android Studio, open your module-level build.gradle.kts or build.gradle file and edit the secrets property. If the secrets property does not exist, add it.

    Edit the properties of the plugin to set propertiesFileName to secrets.properties, set defaultPropertiesFileName to local.defaults.properties, and set any other properties.

    Kotlin

    secrets {
    // To add your Maps API key to this project:
    // 1. If the secrets.properties file does not exist, create it in the same folder as the local.properties file.
    // 2. Add this line, where YOUR_API_KEY is your API key:
    //        MAPS_API_KEY=YOUR_API_KEY
    propertiesFileName = "secrets.properties"

    // A properties file containing default secret values. This file can be
    // checked in version control.
    defaultPropertiesFileName = "local.defaults.properties"
}

    Groovy

    secrets {
    // To add your Maps API key to this project:
    // 1. If the secrets.properties file does not exist, create it in the same folder as the local.properties file.
    // 2. Add this line, where YOUR_API_KEY is your API key:
    //        MAPS_API_KEY=YOUR_API_KEY
    propertiesFileName = "secrets.properties"

    // A properties file containing default secret values. This file can be
    // checked in version control.
    defaultPropertiesFileName = "local.defaults.properties"
}

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