Embed the Zipline app in Android app assets

build-support/build.gradle

@@ -31,6 +31,7 @@ dependencies {
   implementation libs.spotlessPlugin
   implementation libs.androidGradlePlugin
   implementation libs.jetbrains.compose.gradlePlugin
+  implementation libs.zipline
 
   // Expose the generated version catalog API to the plugin.
   implementation(files(libs.class.superclass.protectionDomain.codeSource.location))

build-support/src/main/kotlin/app/cash/redwood/buildsupport/RedwoodBuildExtension.kt

@@ -26,6 +26,16 @@ interface RedwoodBuildExtension {
    */
   fun publishing()
 
-  /** Bundle a zip with dependencies and startup scripts. */
-  fun application(name: String, mainClass: String)
+  /** Bundle a zip with dependencies and startup scripts for a CLI. */
+  fun cliApplication(name: String, mainClass: String)
+
+  /** Bundle a zip of a Zipline application's compiled `.zipline` files. */
+  fun ziplineApplication()
+
+  /**
+   * Consume a Zipline application in an Android application and embed it within assets.
+   *
+   * @name Name of the Treehouse application. Will be used to prefix the Zipline manifest file.
+   */
+  fun embedZiplineApplication(dependencyNotation: Any, name: String)
 }

build-support/src/main/kotlin/app/cash/redwood/buildsupport/RedwoodBuildPlugin.kt

@@ -24,9 +24,11 @@ import org.gradle.accessors.dm.LibrariesForLibs
 import org.gradle.api.JavaVersion
 import org.gradle.api.Plugin
 import org.gradle.api.Project
+import org.gradle.api.attributes.Attribute
 import org.gradle.api.plugins.JavaApplication
 import org.gradle.api.publish.PublishingExtension
 import org.gradle.api.publish.maven.MavenPublication
+import org.gradle.api.tasks.bundling.Zip
 import org.gradle.api.tasks.compile.JavaCompile
 import org.gradle.api.tasks.testing.AbstractTestTask
 import org.gradle.api.tasks.testing.logging.TestExceptionFormat.FULL
@@ -344,7 +346,7 @@ private class RedwoodBuildExtensionImpl(private val project: Project) : RedwoodB
     }
   }
 
-  override fun application(name: String, mainClass: String) {
+  override fun cliApplication(name: String, mainClass: String) {
     project.plugins.apply("application")
 
     val application = project.extensions.getByName("application") as JavaApplication
@@ -374,4 +376,74 @@ private class RedwoodBuildExtensionImpl(private val project: Project) : RedwoodB
       }
     }
   }
+
+  override fun ziplineApplication() {
+    var hasZipline = false
+    project.afterEvaluate {
+      check(hasZipline) {
+        "Project ${project.path} must have Zipline plugin to create Zipline application"
+      }
+    }
+    project.plugins.withId("app.cash.zipline") {
+      hasZipline = true
+
+      val ziplineConfiguration = project.configurations.create("zipline") {
+        it.isVisible = false
+        it.isCanBeResolved = false
+        it.isCanBeConsumed = true
+        it.attributes {
+          it.attribute(ziplineAttribute, ziplineAttributeValue)
+        }
+      }
+
+      // Only a single file can be used as an artifact so zip up the compiled contents.
+      val zipTask = project.tasks.register("zipProductionZiplineFiles", Zip::class.java) {
+        // Note: This makes assumptions about our setup having a JS target with the default name.
+        it.from(project.tasks.named("compileProductionExecutableKotlinJsZipline"))
+        it.destinationDirectory.set(project.layout.buildDirectory.dir("libs"))
+        it.archiveClassifier.set("zipline")
+      }
+
+      project.artifacts.add(ziplineConfiguration.name, zipTask)
+    }
+  }
+
+  override fun embedZiplineApplication(dependencyNotation: Any, name: String) {
+    var hasApplication = false
+    project.afterEvaluate {
+      check(hasApplication) {
+        "Project ${project.path} must have Android Application plugin to embed Zipline application"
+      }
+    }
+    project.plugins.withId("com.android.application") {
+      hasApplication = true
+
+      // Note: This will crash if you call it twice. We don't need this today, so it's not supported.
+      val ziplineConfiguration = project.configurations.create("zipline") {
+        it.isVisible = false
+        it.isCanBeResolved = true
+        it.isCanBeConsumed = false
+        it.attributes {
+          it.attribute(ziplineAttribute, ziplineAttributeValue)
+        }
+      }
+      project.dependencies.add(ziplineConfiguration.name, dependencyNotation)
+
+      val task = project.tasks.register("copyEmbeddedZiplineApplication", ZiplineAppAssetCopyTask::class.java) {
+        it.appName.set(name)
+        it.files.setFrom(ziplineConfiguration)
+      }
+
+      val androidComponents = project.extensions.getByType(AndroidComponentsExtension::class.java)
+      androidComponents.onVariants {
+        val assets = checkNotNull(it.sources.assets) {
+          "Project ${project.path} assets must be enabled to embed Zipline application"
+        }
+        assets.addGeneratedSourceDirectory(task, ZiplineAppAssetCopyTask::outputDirectory)
+      }
+    }
+  }
 }
+
+private val ziplineAttribute = Attribute.of("zipline", String::class.java)
+private const val ziplineAttributeValue = "yep"

build-support/src/main/kotlin/app/cash/redwood/buildsupport/ZiplineAppAssetCopyTask.kt

@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2023 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package app.cash.redwood.buildsupport
+
+import app.cash.zipline.ZiplineManifest
+import javax.inject.Inject
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.ArchiveOperations
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.provider.Property
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+
+private const val ZIPLINE_MANIFEST_JSON = "manifest.zipline.json"
+
+internal abstract class ZiplineAppAssetCopyTask
+@Inject constructor(
+  private val archiveOperations: ArchiveOperations,
+) : DefaultTask() {
+  @get:InputFiles
+  abstract val files: ConfigurableFileCollection
+
+  @get:Input
+  abstract val appName: Property<String>
+
+  @get:OutputDirectory
+  abstract val outputDirectory: DirectoryProperty
+
+  @TaskAction
+  fun execute() {
+    val outputDirectory = outputDirectory.get()
+    outputDirectory.asFile.apply {
+      deleteRecursively()
+      mkdirs()
+    }
+
+    val fileMap = archiveOperations.zipTree(files.singleFile)
+      .files
+      .associateBy { it.name }
+      .toMutableMap()
+
+    val inputManifestFile = checkNotNull(fileMap.remove(ZIPLINE_MANIFEST_JSON)) {
+      "No zipline.manifest.json file found in input files ${fileMap.keys}"
+    }
+    val inputManifest = ZiplineManifest.decodeJson(inputManifestFile.readText())
+
+    // Add a timestamp to the manifest which is required for Zipline to load as an embedded app.
+    val outputManifest = inputManifest.copy(
+      unsigned = inputManifest.unsigned.copy(
+        freshAtEpochMs = System.currentTimeMillis(),
+      ),
+    )
+    val outputManifestFile = outputDirectory.file("${appName.get()}.$ZIPLINE_MANIFEST_JSON").asFile
+    outputManifestFile.writeText(outputManifest.encodeJson())
+
+    // Rewrite all .zipline files to their SHA-256 hashes which is how Zipline loads when embedded.
+    for (module in outputManifest.modules.values) {
+      val inputFile = checkNotNull(fileMap.remove(module.url)) {
+        "No ${module.url} file found in input files as specified by the manifest"
+      }
+      val outputFile = outputDirectory.file(module.sha256.hex()).asFile
+      inputFile.copyTo(outputFile)
+    }
+  }
+}

gradle/libs.versions.toml

@@ -7,6 +7,7 @@ jbCompose = "1.5.2"
 lint = "31.1.1"
 zipline = "1.3.0"
 coil = "2.4.0"
+okio = "3.6.0"
 
 [libraries]
 kotlin-compiler = { module = "org.jetbrains.kotlin:kotlin-compiler", version.ref = "kotlin" }
@@ -62,7 +63,8 @@ junit = { module = "junit:junit", version = "4.13.2" }
 testParameterInjector = { module = "com.google.testparameterinjector:test-parameter-injector", version = "1.12" }
 assertk = "com.willowtreeapps.assertk:assertk:0.27.0"
 robolectric = { module = "org.robolectric:robolectric", version = "4.10.3" }
-okio = { module = "com.squareup.okio:okio", version = "3.6.0" }
+okio = { module = "com.squareup.okio:okio", version.ref = "okio" }
+okio-assetfilesystem = { module = "com.squareup.okio:okio-assetfilesystem", version.ref = "okio" }
 okHttp = { module = "com.squareup.okhttp3:okhttp", version = "4.11.0" }
 paging-compose-common = { module = "app.cash.paging:paging-compose-common", version = "3.2.0-alpha05-0.2.3" }
 zipline = { module = "app.cash.zipline:zipline", version.ref = "zipline" }

redwood-tooling-codegen/build.gradle

@@ -2,7 +2,7 @@ apply plugin: 'org.jetbrains.kotlin.jvm'
 
 redwoodBuild {
   publishing()
-  application('redwood-codegen', 'app.cash.redwood.tooling.codegen.Main')
+  cliApplication('redwood-codegen', 'app.cash.redwood.tooling.codegen.Main')
 }
 
 dependencies {

redwood-tooling-lint/build.gradle

@@ -6,7 +6,7 @@ apply plugin: 'org.jetbrains.kotlin.plugin.serialization'
 
 redwoodBuild {
   publishing()
-  application('redwood-lint', 'app.cash.redwood.tooling.lint.Main')
+  cliApplication('redwood-lint', 'app.cash.redwood.tooling.lint.Main')
 }
 
 dependencies {

redwood-tooling-schema/build.gradle

@@ -6,7 +6,7 @@ apply plugin: 'org.jetbrains.kotlin.plugin.serialization'
 
 redwoodBuild {
   publishing()
-  application('redwood-schema', 'app.cash.redwood.tooling.schema.Main')
+  cliApplication('redwood-schema', 'app.cash.redwood.tooling.schema.Main')
 }
 
 dependencies {

samples/emoji-search/android-composeui/build.gradle

@@ -1,6 +1,10 @@
 apply plugin: 'com.android.application'
 apply plugin: 'org.jetbrains.kotlin.android'
 
+redwoodBuild {
+  embedZiplineApplication(projects.samples.emojiSearch.presenterTreehouse, 'emoji-search')
+}
+
 android {
   namespace 'com.example.redwood.emojisearch.android.composeui'
 
@@ -28,4 +32,5 @@ dependencies {
   implementation projects.redwoodTreehouseHost
   implementation projects.redwoodTreehouseHostComposeui
   implementation projects.redwoodWidgetCompose
+  implementation libs.okio.assetfilesystem
 }

samples/emoji-search/android-composeui/src/main/kotlin/com/example/redwood/emojisearch/android/composeui/EmojiSearchActivity.kt

@@ -52,6 +52,8 @@ import kotlinx.coroutines.cancel
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.launch
 import okhttp3.OkHttpClient
+import okio.Path.Companion.toPath
+import okio.assetfilesystem.asFileSystem
 
 @NoLiveLiterals
 class EmojiSearchActivity : ComponentActivity() {
@@ -128,6 +130,8 @@ class EmojiSearchActivity : ComponentActivity() {
       httpClient = httpClient,
       manifestVerifier = ManifestVerifier.Companion.NO_SIGNATURE_CHECKS,
       eventListener = appEventListener,
+      embeddedDir = "/".toPath(),
+      embeddedFileSystem = applicationContext.assets.asFileSystem(),
     )
 
     val manifestUrlFlow = flowOf("http://10.0.2.2:8080/manifest.zipline.json")

samples/emoji-search/android-views/build.gradle

@@ -1,6 +1,10 @@
 apply plugin: 'com.android.application'
 apply plugin: 'org.jetbrains.kotlin.android'
 
+redwoodBuild {
+  embedZiplineApplication(projects.samples.emojiSearch.presenterTreehouse, 'emoji-search')
+}
+
 android {
   namespace "com.example.redwood.emojisearch.android.views"
 }
@@ -18,4 +22,5 @@ dependencies {
   implementation projects.redwoodLazylayoutView
   implementation projects.redwoodTreehouse
   implementation projects.redwoodTreehouseHost
+  implementation libs.okio.assetfilesystem
 }

samples/emoji-search/android-views/src/main/kotlin/com/example/redwood/emojisearch/android/views/EmojiSearchActivity.kt

@@ -48,6 +48,8 @@ import kotlinx.serialization.json.Json
 import okhttp3.OkHttpClient
 import okio.FileSystem
 import okio.Path.Companion.toOkioPath
+import okio.Path.Companion.toPath
+import okio.assetfilesystem.asFileSystem
 
 class EmojiSearchActivity : ComponentActivity() {
   private val scope: CoroutineScope = CoroutineScope(Main)
@@ -119,6 +121,8 @@ class EmojiSearchActivity : ComponentActivity() {
       httpClient = httpClient,
       manifestVerifier = ManifestVerifier.NO_SIGNATURE_CHECKS,
       eventListener = appEventListener,
+      embeddedDir = "/".toPath(),
+      embeddedFileSystem = applicationContext.assets.asFileSystem(),
       stateStore = FileStateStore(
         json = Json,
         fileSystem = FileSystem.SYSTEM,

samples/emoji-search/presenter-treehouse/build.gradle

@@ -1,6 +1,10 @@
 apply plugin: 'org.jetbrains.kotlin.multiplatform'
 apply plugin: 'app.cash.zipline'
 
+redwoodBuild {
+  ziplineApplication()
+}
+
 kotlin {
   iosArm64()
   iosX64()