👷 Update CI to allow external PRs

Updating the CI flow to build the app (which generates a release apk) to
run with fake credentials if the user has no access to the GitHub
secrets. This allows Alkaa to receive external PRs.

.github/workflows/build.yml

@@ -31,4 +31,5 @@ jobs:
         env:
           ALKAA_KEY_ALIAS: ${{ secrets.ALKAA_KEY_ALIAS }}
           ALKAA_KEY_PASSWORD: ${{ secrets.ALKAA_KEY_PASSWORD }}
-          ALKAA_KEY_STORE_PASSWORD: ${{ secrets.ALKAA_KEY_STORE_PASSWORD }}
+          ALKAA_KEY_STORE_PASSWORD: ${{ secrets.ALKAA_KEY_ALIAS_PASSWORD }}
+          ALKAA_STORE_PATH: ${{ secrets.ALKAA_STORE_PATH }}

app/build.gradle.kts

@@ -1,5 +1,6 @@
 import com.android.build.api.dsl.ManagedVirtualDevice
 import com.android.build.gradle.internal.tasks.factory.dependsOn
+import java.util.Properties
 
 plugins {
     id("com.android.application")
@@ -23,12 +24,13 @@ android {
         setProperty("archivesBaseName", "${parent?.name}-$versionName")
     }
 
+    val props = readProperties(file("../config/signing/signing.properties"))
     signingConfigs {
         create("release") {
-            keyAlias = System.getenv("ALKAA_KEY_ALIAS")
-            keyPassword = System.getenv("ALKAA_KEY_PASSWORD")
-            storeFile = file("../config/signing/alkaa-keystore")
-            storePassword = System.getenv("ALKAA_KEY_STORE_PASSWORD")
+            keyAlias = System.getenv("ALKAA_KEY_ALIAS") ?: props.getStringProperty("keyAlias")
+            keyPassword = System.getenv("ALKAA_KEY_PASSWORD") ?: props.getStringProperty("keyPassword")
+            storeFile = file(System.getenv("ALKAA_STORE_PATH") ?: props.getStringProperty("storePath"))
+            storePassword = System.getenv("ALKAA_KEY_STORE_PASSWORD") ?: props.getStringProperty("storePassword")
         }
     }
 
@@ -145,3 +147,12 @@ dependencies {
         exclude(group = "androidx.lifecycle", module = "lifecycle-runtime")
     }
 }
+
+fun readProperties(propertiesFile: File) = Properties().apply {
+    propertiesFile.inputStream().use { fis ->
+        load(fis)
+    }
+}
+
+fun Properties.getStringProperty(key: String): String =
+    getProperty(key) ?: throw IllegalStateException("Property $key not found")

config/signing/signing.properties

@@ -0,0 +1,4 @@
+keyAlias=key0
+keyPassword=alkaa123
+storePath=../config/signing/testing-keystore
+storePassword=alkaa123