chore(build): Refactor Gradle build scripts to Kotlin DSL (#1944)

.github/workflows/android.yml

@@ -103,7 +103,7 @@ jobs:
     timeout-minutes: 30
     strategy:
       matrix:
-        api-level: [26, 34]
+        api-level: [26, 35]
 
     steps:
       - uses: actions/checkout@v4

.github/workflows/release.yml

@@ -18,8 +18,8 @@ jobs:
 
     - name: Get `versionCode` & `versionName`
       run: |
-        echo "versionCode=$(grep -oP 'versionCode \K\d+' ./app/build.gradle)" >> $GITHUB_ENV
-        echo "versionName=$(grep -oP 'versionName \"\K[^\"]+' ./app/build.gradle)" >> $GITHUB_ENV
+        echo "versionCode=$(grep -oP 'VERSION_CODE = \K\d+' ./buildSrc/src/main/kotlin/Configs.kt)" >> $GITHUB_ENV
+        echo "versionName=$(grep -oP 'VERSION_NAME = \"\K[^\"]+' ./buildSrc/src/main/kotlin/Configs.kt)" >> $GITHUB_ENV
 
     - name: Validate Gradle wrapper
       uses: gradle/actions/wrapper-validation@v4
@@ -48,7 +48,7 @@ jobs:
       run: ./gradlew assembleFdroidRelease
 
     - name: Enable Crashlytics
-      run: sed -i 's/useCrashlytics = false/useCrashlytics = true/g' ./build.gradle
+      run: sed -i 's/USE_CRASHLYTICS = false/USE_CRASHLYTICS = true/g' ./buildSrc/src/main/kotlin/Configs.kt
 
     - name: Build Play Store release
       run: ./gradlew bundleGoogleRelease assembleGoogleRelease

.gitignore

@@ -15,6 +15,7 @@
 .externalNativeBuild
 .cxx
 /app/release
+/buildSrc/build
 
 # Java KeyStore certificates
 *.jks

app/build.gradle

@@ -27,13 +27,13 @@ android {
             storePassword keystoreProperties['storePassword']
         }
     }
-    compileSdk 36
+    compileSdk Configs.COMPILE_SDK
     defaultConfig {
-        applicationId "com.geeksville.mesh"
-        minSdkVersion 23
-        targetSdk 36
-        versionCode 30603 // format is Mmmss (where M is 1+the numeric major number
-        versionName "2.6.3"
+        applicationId Configs.APPLICATION_ID
+        minSdkVersion Configs.MIN_SDK_VERSION
+        targetSdk Configs.TARGET_SDK
+        versionCode Configs.VERSION_CODE // format is Mmmss (where M is 1+the numeric major number
+        versionName Configs.VERSION_NAME
         testInstrumentationRunner "com.geeksville.mesh.TestRunner"
 
         // per https://developer.android.com/studio/write/vector-asset-studio
@@ -49,7 +49,7 @@ android {
         }
         google {
             dimension = 'default'
-            if (useCrashlytics) {
+            if (Configs.USE_CRASHLYTICS) {
                 apply plugin: 'com.google.gms.google-services'
                 apply plugin: 'com.google.firebase.crashlytics'
             }

build.gradle

@@ -1,51 +0,0 @@
-// Top-level build file where you can add configuration options common to all sub-projects/modules.
-
-buildscript {
-    ext {
-        useCrashlytics = false
-    }
-
-    repositories {
-        google()
-        mavenCentral()
-    }
-    dependencies {
-        classpath libs.agp
-        classpath libs.kotlin.gradle.plugin
-        classpath libs.kotlin.serialization
-
-        // NOTE: Do not place your application dependencies here; they belong
-        // in the individual module build.gradle files
-
-        // Firebase Crashlytics
-        if (useCrashlytics) {
-            classpath libs.google.services
-            classpath libs.firebase.crashlytics.gradle
-        }
-
-        // protobuf plugin - docs here https://github.com/google/protobuf-gradle-plugin
-        classpath libs.protobuf.gradle.plugin
-
-        classpath libs.hilt.android.gradle.plugin
-    }
-}
-
-plugins {
-    alias (libs.plugins.kotlin.jvm) apply false
-    alias (libs.plugins.devtools.ksp) apply false
-    alias (libs.plugins.compose) apply false
-}
-
-allprojects {
-    repositories {
-        google()
-        mavenCentral()
-        // jcenter()
-        maven { url 'https://jitpack.io' }
-        //maven { url "https://plugins.gradle.org/m2/" }
-    }
-}
-
-task clean(type: Delete) {
-    delete rootProject.buildDir
-}

build.gradle.kts

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2025 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+buildscript {
+    repositories {
+        google()
+        mavenCentral()
+    }
+    dependencies {
+        classpath(libs.agp)
+        classpath(libs.kotlin.gradle.plugin)
+        classpath(libs.kotlin.serialization)
+
+        // Google Play Services and Firebase Crashlytics
+        // If you want to use Firebase Crashlytics,
+        // set Configs.USE_CRASHLYTICS to true in:
+        // buildSrc/src/main/kotlin/Configs.kt
+        // Disabled by default for fdroid builds
+        if (Configs.USE_CRASHLYTICS) {
+            classpath(libs.google.services)
+            classpath(libs.firebase.crashlytics.gradle)
+        }
+
+        classpath(libs.protobuf.gradle.plugin)
+        classpath(libs.hilt.android.gradle.plugin)
+    }
+}
+
+plugins {
+    alias(libs.plugins.kotlin.jvm) apply false
+    alias(libs.plugins.devtools.ksp) apply false
+    alias(libs.plugins.compose) apply false
+}
+
+allprojects {
+    repositories {
+        google()
+        mavenCentral()
+        maven { url = uri("https://jitpack.io") }
+    }
+}
+
+tasks.register<Delete>("clean") {
+    delete(layout.buildDirectory)
+}

buildSrc/build.gradle.kts

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2025 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+plugins {
+    `kotlin-dsl`
+}
+
+repositories {
+    mavenCentral()
+}

buildSrc/src/main/kotlin/Configs.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2025 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+object Configs {
+    const val APPLICATION_ID = "com.geeksville.mesh"
+    const val MIN_SDK_VERSION = 23
+    const val TARGET_SDK = 36
+    const val COMPILE_SDK = 36
+    const val VERSION_CODE = 30603 // format is Mmmss (where M is 1+the numeric major number
+    const val VERSION_NAME = "2.6.3"
+    const val USE_CRASHLYTICS = true // Set to false if you don't want to use Firebase Crashlytics
+}

settings.gradle

@@ -1,3 +0,0 @@
-include ':app'
-rootProject.name='Meshtastic Android'
-include ':network'

settings.gradle.kts

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2025 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+include(":app", ":network")
+rootProject.name = "Meshtastic Android"