[#8] Restrict maven repositories

This improves security by ensuring that Google's dependencies only from the Google Maven repo.

A dependency on Jitpack has also been removed.

build-conventions/settings.gradle.kts

@@ -1,14 +1,32 @@
-pluginManagement {
-    repositories {
-        gradlePluginPortal()
-    }
-}
-
 @Suppress("UnstableApiUsage")
 dependencyResolutionManagement {
     repositories {
-        mavenCentral()
+        val isRepoRestrictionEnabled = true
-        google()
+
+        maven("https://dl.google.com/dl/android/maven2/") { //google()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    includeGroup("androidx.navigation")
+                    includeGroup("com.android.tools")
+                    includeGroup("com.google.testing.platform")
+                    includeGroupByRegex("androidx.*")
+                    includeGroupByRegex("com\\.android.*")
+                    includeGroupByRegex("com\\.android\\.tools.*")
+                }
+            }
+        }
+        maven("https://repo.maven.apache.org/maven2/") { // mavenCentral()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    excludeGroup("androidx.navigation")
+                    excludeGroup("com.android.tools")
+                    excludeGroup("com.google.testing.platform")
+                    excludeGroupByRegex("androidx.*")
+                    excludeGroupByRegex("com\\.android.*")
+                    excludeGroupByRegex("com\\.android\\.tools.*")
+                }
+            }
+        }
     }
 }
 

build.gradle.kts

@@ -1,11 +1,43 @@
-import org.gradle.internal.impldep.org.junit.experimental.categories.Categories.CategoryFilter.exclude
-
 buildscript {
     repositories {
-        google()
+        val isRepoRestrictionEnabled = true
-        mavenCentral()
+
-        maven("https://jitpack.io")
+        maven("https://dl.google.com/dl/android/maven2/") { //google()
-        gradlePluginPortal()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    includeGroup("androidx.navigation")
+                    includeGroup("com.android.tools")
+                    includeGroup("com.google.testing.platform")
+                    includeGroupByRegex("androidx.*")
+                    includeGroupByRegex("com\\.android.*")
+                    includeGroupByRegex("com\\.android\\.tools.*")
+                }
+            }
+        }
+        maven("https://plugins.gradle.org/m2/") { // gradlePluginPortal()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    excludeGroup("androidx.navigation")
+                    excludeGroup("com.android.tools")
+                    excludeGroup("com.google.testing.platform")
+                    excludeGroupByRegex("androidx.*")
+                    excludeGroupByRegex("com\\.android.*")
+                    excludeGroupByRegex("com\\.android\\.tools.*")
+                }
+            }
+        }
+        maven("https://repo.maven.apache.org/maven2/") { // mavenCentral()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    excludeGroup("androidx.navigation")
+                    excludeGroup("com.android.tools")
+                    excludeGroup("com.google.testing.platform")
+                    excludeGroupByRegex("androidx.*")
+                    excludeGroupByRegex("com\\.android.*")
+                    excludeGroupByRegex("com\\.android\\.tools.*")
+                }
+            }
+        }
     }
     dependencies {
         classpath("com.android.tools.build:gradle:${properties["ANDROID_GRADLE_PLUGIN_VERSION"]}")

docs/Architecture.md

@@ -6,6 +6,7 @@ _Note: This document will continue to be updated as the app is implemented._
  * Much of the Gradle configuration lives in [build-conventions](../build-conventions/) to prevent repetitive configuration as additional modules are added to the project
  * Build scripts are written in Kotlin, so that a single language is used across build and the app code bases
  * Only Gradle, Google, and JetBrains plug-ins are included in the critical path.  Third party plug-ins can be used, but they're outside the critical path.  For example, the Gradle Versions Plugin could be removed and wouldn't negative impact building, testing, or deploying the app
+ * Repository restrictions are enabled in [build-conventions](../build-conventions/settings.gradle.kts), [settings.gradle.kts](../settings.gradle.kts), and [build.gradle.kts](../build.gradle.kts) to reduce likelihood of pulling in an incorrect dependency.  If adding a new dependency, these restrictions may need to be changed otherwise an error that the dependency cannot be found will be displayed
 
 # Multiplatform
 While this repository is for an Android application, efforts are made to give multiplatform flexibility in the future.  Specific adaptions that are being made:
@@ -26,6 +27,6 @@ The logical components of the app are implemented as a number of Gradle modules.
  * build-info-lib — Collects information from the build environment (e.g. Git SHA, Git commit count) and compiles them into the application.  Can also be used for injection of API keys or other secrets.
  * ui-lib — User interface that the user interacts with.  This contains 99% of the UI code, along with localizations, icons, and other assets.
  * preference
-     * preference-api-lib — Multiplatform interfaces for key-value storage of preferences
+     * preference-api-lib — Multiplatform interfaces for key-value storage of preferences.
-     * preference-impl-android-lib — Android-specific implementation for preference storage
+     * preference-impl-android-lib — Android-specific implementation for preference storage.
- * test-lib — Provides common test utilities
+ * test-lib — Provides common test utilities.

docs/Setup.md

@@ -34,6 +34,7 @@ Start by making sure the command line with Gradle works first, because **all the
 3. Run Gradle with the argument `--rerun-tasks` which will effectively disable the build cache by re-running tasks and repopulating the cache.  E.g. `./gradlew assemble --rerun-tasks`
 4. Reboot your computer, which will ensure that Gradle and Kotlin daemons are completely killed and relaunched
 5. Delete the global Gradle cache under `~/.gradle/caches`
+6. If adding a new dependency or updating a dependency, a warning that a dependency cannot be found may indicate the Maven repository restrictions need adjusting
 
 ## Gradle Tasks
 A variety of Gradle tasks are set up within the project, and these tasks are also accessible in Android Studio as run configurations.

gradle.properties

@@ -47,7 +47,7 @@ ANDROID_NDK_VERSION=23.0.7599858
 
 ANDROID_GRADLE_PLUGIN_VERSION=7.0.3
 DETEKT_VERSION=1.18.1
-GRADLE_VERSIONS_PLUGIN_VERSION=0.38.0
+GRADLE_VERSIONS_PLUGIN_VERSION=0.39.0
 KTLINT_VERSION=0.42.1
 JGIT_VERSION=5.12.0.202106070339-r
 

settings.gradle.kts

@@ -2,11 +2,6 @@ enableFeaturePreview("VERSION_CATALOGS")
 enableFeaturePreview("TYPESAFE_PROJECT_ACCESSORS")
 
 pluginManagement {
-    repositories {
-        gradlePluginPortal()
-        google()
-    }
-
     plugins {
         val detektVersion = extra["DETEKT_VERSION"].toString()
         val gradleVersionsPluginVersion = extra["GRADLE_VERSIONS_PLUGIN_VERSION"].toString()
@@ -22,9 +17,30 @@ pluginManagement {
 dependencyResolutionManagement {
     @Suppress("UnstableApiUsage")
     repositories {
-        google()
+        val isRepoRestrictionEnabled = true
-        mavenCentral()
+
-        maven("https://jitpack.io")
+        maven("https://dl.google.com/dl/android/maven2/") { // google()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    includeGroup("android.arch.lifecycle")
+                    includeGroup("android.arch.core")
+                    includeGroup("com.google.android.material")
+                    includeGroupByRegex("androidx.*")
+                    includeGroupByRegex("com\\.android.*")
+                }
+            }
+        }
+        maven("https://repo.maven.apache.org/maven2/") { // mavenCentral()
+            if (isRepoRestrictionEnabled) {
+                content {
+                    excludeGroup("android.arch.lifecycle")
+                    excludeGroup("android.arch.core")
+                    excludeGroup("com.google.android.material")
+                    excludeGroupByRegex("androidx.*")
+                    excludeGroupByRegex("com\\.android.*")
+                }
+            }
+        }
     }
 
     @Suppress("UnstableApiUsage", "MaxLineLength")