Embed the Zipline app in Android app assets

This allows the app to function without the server running, or without ever having to had connect to the server in the past. It will also allow automated testing of these applications in the future.

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 +376,73 @@ 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)
+        }
+      }
+
+      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 +1,78 @@
+/*
+ * 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 zipFile = files.singleFile
+    val fileMap = archiveOperations.zipTree(zipFile)
+      .files
+      .associateBy { it.name }
+      .toMutableMap()
+    val inputManifestFile = checkNotNull(fileMap.remove(ZIPLINE_MANIFEST_JSON)) {
+      "No zipline.manifest.json file found in input files ${fileMap.keys}"
+    }
+    val inputManifest = ZiplineManifest.decodeJson(inputManifestFile.readText())
+    val outputManifest = inputManifest.copy(
+      unsigned = inputManifest.unsigned.copy(
+        freshAtEpochMs = System.currentTimeMillis(),
+      )
+    )
+
+    val outputDirectory = outputDirectory.get()
+    outputDirectory.asFile.apply {
+      deleteRecursively()
+      mkdirs()
+    }
+
+    val outputManifestFile = outputDirectory.file("${appName.get()}.$ZIPLINE_MANIFEST_JSON").asFile
+    outputManifestFile.writeText(outputManifest.encodeJson())
+
+    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()