Refactor Vendor Plugin (#6640)

Per [b/391351857](https://b.corp.google.com/issues/391351857),

This refactors the `VendorPlugin` and `VendorTask` to be more compliant
with the gradle cache and configuration avoidance. It also adds proper
task logging and documentation to both the task and the plugin.

This PR also fixes the following:

- [b/391352175](https://b.corp.google.com/issues/391352175) -> Rename
plugin Util files to Extensions

Author: daymxn

.github/workflows/ci_tests.yml

@@ -119,6 +119,7 @@ jobs:
         module: ${{ fromJSON(needs.determine_changed.outputs.modules) }}
         exclude:
           - module: :firebase-firestore
+          - module: :firebase-functions:ktx
 
     steps:
       - uses: actions/checkout@v4.1.1

plugins/build.gradle.kts

@@ -1,16 +1,18 @@
-// Copyright 2018 Google LLC
-//
-// 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.
+/*
+ * Copyright 2018 Google LLC
+ *
+ * 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.
+ */
 
 plugins {
   alias(libs.plugins.kotlinx.serialization)
@@ -26,6 +28,8 @@ repositories {
   maven(url = "https://plugins.gradle.org/m2/")
 }
 
+group = "com.google.firebase"
+
 spotless {
   java {
     target("src/**/*.java")

plugins/src/main/java/com/google/firebase/gradle/plugins/ClosureUtil.java

@@ -16,14 +16,22 @@
 
 package com.google.firebase.gradle.plugins
 
+import com.android.build.api.variant.LibraryAndroidComponentsExtension
+import com.android.build.api.variant.LibraryVariant
+import java.io.BufferedOutputStream
 import java.io.File
+import java.util.zip.ZipEntry
+import java.util.zip.ZipOutputStream
 import org.gradle.api.DefaultTask
 import org.gradle.api.Project
+import org.gradle.api.Task
 import org.gradle.api.artifacts.Dependency
 import org.gradle.api.attributes.Attribute
 import org.gradle.api.attributes.AttributeContainer
+import org.gradle.api.plugins.PluginManager
 import org.gradle.api.provider.Provider
 import org.gradle.kotlin.dsl.apply
+import org.gradle.kotlin.dsl.provideDelegate
 import org.gradle.workers.WorkAction
 import org.gradle.workers.WorkParameters
 import org.gradle.workers.WorkQueue
@@ -165,7 +173,7 @@ inline fun <reified T> attributeFrom(name: String) = Attribute.of(name, T::class
  * attribute(Attribute.of(name, T::class.java), value)
  * ```
  */
-inline fun <reified T> AttributeContainer.attribute(name: String, value: T) =
+inline fun <reified T : Any> AttributeContainer.attribute(name: String, value: T) =
   attribute(attributeFrom(name), value)
 
 /**
@@ -174,8 +182,7 @@ inline fun <reified T> AttributeContainer.attribute(name: String, value: T) =
  * pluginManager.apply(T::class)
  * ```
  */
-inline fun <reified T : Any> org.gradle.api.plugins.PluginManager.`apply`(): Unit =
-  `apply`(T::class)
+inline fun <reified T : Any> PluginManager.apply(): Unit = apply(T::class)
 
 /**
  * The name provided to this artifact when published.
@@ -186,4 +193,54 @@ inline fun <reified T : Any> org.gradle.api.plugins.PluginManager.`apply`(): Uni
  * ```
  */
 val Dependency.artifactName: String
-  get() = listOf(group, name, version).filterNotNull().joinToString(":")
+  get() = listOfNotNull(group, name, version).joinToString(":")
+
+/**
+ * Creates an archive of this directory at the [dest] file.
+ *
+ * Should only be ran within the context of a [Task], as outside of a [Task] so you should likely be
+ * using the `copy` or `sync` tasks instead.
+ */
+fun File.zipFilesTo(task: Task, dest: File): File {
+  val logger = task.logger
+
+  logger.info("Zipping '$absolutePath' to '${dest.absolutePath}'")
+
+  logger.debug("Ensuring parent directories are present for zip file")
+  dest.parentFile?.mkdirs()
+
+  logger.debug("Creating empty zip file to write to")
+  dest.createNewFile()
+
+  logger.debug("Packing file contents into zip")
+  ZipOutputStream(BufferedOutputStream(dest.outputStream())).use { zipFile ->
+    for (file in walk().filter { it.isFile }) {
+      val relativePath = file.relativeTo(this).unixPath
+      logger.debug("Adding file to zip: $relativePath")
+
+      zipFile.putNextEntry(ZipEntry(relativePath))
+      file.inputStream().use { it.copyTo(zipFile) }
+      zipFile.closeEntry()
+    }
+  }
+
+  return dest
+}
+
+/**
+ * Bind a callback to run whenever there are release variants for this android build.
+ *
+ * Syntax sugar for:
+ * ```
+ * components.onVariants(components.selector().withBuildType("release")) {
+ *  // ...
+ * }
+ * ```
+ *
+ * @see LibraryAndroidComponentsExtension.onVariants
+ */
+fun LibraryAndroidComponentsExtension.onReleaseVariants(
+  callback: (variant: LibraryVariant) -> Unit
+) {
+  onVariants(selector().withBuildType("release"), callback)
+}

plugins/src/main/java/com/google/firebase/gradle/plugins/GradleUtils.kt renamed to plugins/src/main/java/com/google/firebase/gradle/plugins/GradleExtensions.kt

@@ -16,6 +16,7 @@
 
 package com.google.firebase.gradle.plugins
 
+import java.io.File
 import org.w3c.dom.Element
 import org.w3c.dom.NodeList
 
@@ -26,16 +27,14 @@ fun String.remove(regex: Regex) = replace(regex, "")
 fun String.remove(str: String) = replace(str, "")
 
 /**
- * Returns a sequence containing all elements.
- *
- * The operation is _terminal_.
+ * Joins a variable amount of [strings][Any.toString] to a single [String] split by newlines (`\n`).
  *
- * Syntax sugar for:
- * ```
- * take(count())
+ * For example:
+ * ```kotlin
+ * println(multiLine("Hello", "World", "!")) // "Hello\nWorld\n!"
  * ```
  */
-public fun <T> Sequence<T>.takeAll(): Sequence<T> = take(count())
+fun multiLine(vararg strings: Any?) = strings.joinToString("\n")
 
 /**
  * Converts an [Element] to an Artifact string.
@@ -77,19 +76,30 @@ fun Element.toArtifactString() =
  * ```
  *
  * @throws NoSuchElementException if the [Element] does not have descendant [Element]s with tags
- *   that match the components of an Artifact string; groupId, artifactId, version.
+ *   that match the components of an Artifact string; groupId and artifactId.
  */
 fun Element.toMavenName() = "${textByTag("groupId")}:${textByTag("artifactId")}"
 
 /**
- * Finds a descendant [Element] by a given [tag], and returns the [textContent]
- * [Element.getTextContent] of it.
+ * Finds a descendant [Element] by a [tag], and returns the [textContent][Element.getTextContent] of
+ * it.
  *
  * @param tag the XML tag to filter for (the special value "*" matches all tags)
  * @throws NoSuchElementException if an [Element] with the given [tag] does not exist
  * @see findElementsByTag
+ * @see textByTagOrNull
+ */
+fun Element.textByTag(tag: String) =
+  textByTagOrNull(tag) ?: throw RuntimeException("Element tag was missing: $tag")
+
+/**
+ * Finds a descendant [Element] by a [tag], and returns the [textContent][Element.getTextContent] of
+ * it, or null if it couldn't be found.
+ *
+ * @param tag the XML tag to filter for (the special value "*" matches all tags)
+ * @see textByTag
  */
-fun Element.textByTag(tag: String) = findElementsByTag(tag).first().textContent
+fun Element.textByTagOrNull(tag: String) = findElementsByTag(tag).firstOrNull()?.textContent
 
 /**
  * Finds a descendant [Element] by a given [tag], or creates a new one.
@@ -99,7 +109,7 @@ fun Element.textByTag(tag: String) = findElementsByTag(tag).first().textContent
  * @param tag the XML tag to filter for (the special value "*" matches all tags)
  * @see findElementsByTag
  */
-fun Element.findOrCreate(tag: String) =
+fun Element.findOrCreate(tag: String): Element =
   findElementsByTag(tag).firstOrNull() ?: ownerDocument.createElement(tag).also { appendChild(it) }
 
 /**
@@ -118,27 +128,21 @@ fun Element.findElementsByTag(tag: String) =
  * Yields the items of this [NodeList] as a [Sequence].
  *
  * [NodeList] does not typically offer an iterator. This extension method offers a means to loop
- * through a NodeList's [item][NodeList.item] method, while also taking into account its [length]
- * [NodeList.getLength] property to avoid an [IndexOutOfBoundsException].
+ * through a NodeList's [item][NodeList.item] method, while also taking into account the element's
+ * [length][NodeList.getLength] property to avoid an [IndexOutOfBoundsException].
  *
  * Additionally, this operation is _intermediate_ and _stateless_.
  */
-fun NodeList.children() = sequence {
-  for (index in 0..length) {
-    yield(item(index))
+fun NodeList.children(removeDOMSections: Boolean = true) = sequence {
+  for (index in 0 until length) {
+    val child = item(index)
+
+    if (!removeDOMSections || !child.nodeName.startsWith("#")) {
+      yield(child)
+    }
   }
 }
 
-/**
- * Joins a variable amount of [strings][Any.toString] to a single [String] split by newlines (`\n`).
- *
- * For example:
- * ```kotlin
- * println(multiLine("Hello", "World", "!")) // "Hello\nWorld\n!"
- * ```
- */
-fun multiLine(vararg strings: Any?) = strings.joinToString("\n")
-
 /**
  * Returns the first match of a regular expression in the [input], beginning at the specified
  * [startIndex].
@@ -152,6 +156,26 @@ fun Regex.findOrThrow(input: CharSequence, startIndex: Int = 0) =
   find(input, startIndex)
     ?: throw RuntimeException(multiLine("No match found for the given input:", input.toString()))
 
+/**
+ * Returns the value of the first capture group.
+ *
+ * Intended to be used in [MatchResult] that are only supposed to capture a single entry.
+ */
+val MatchResult.firstCapturedValue: String
+  get() = groupValues[1]
+
+/**
+ * Returns a sequence containing all elements.
+ *
+ * The operation is _terminal_.
+ *
+ * Syntax sugar for:
+ * ```
+ * take(count())
+ * ```
+ */
+fun <T> Sequence<T>.takeAll(): Sequence<T> = take(count())
+
 /**
  * Creates a [Pair] out of an [Iterable] with only two elements.
  *
@@ -212,14 +236,6 @@ fun List<String>.replaceMatches(regex: Regex, transform: (MatchResult) -> String
   }
 }
 
-/**
- * Returns the value of the first capture group.
- *
- * Intended to be used in [MatchResult] that are only supposed to capture a single entry.
- */
-val MatchResult.firstCapturedValue: String
-  get() = groupValues[1]
-
 /**
  * Creates a diff between two lists.
  *
@@ -250,3 +266,23 @@ infix fun <T> List<T>.diff(other: List<T>): List<Pair<T?, T?>> {
  * ```
  */
 fun <T> List<T>.coerceToSize(targetSize: Int) = List(targetSize) { getOrNull(it) }
+
+/**
+ * The [path][File.path] represented as a qualified unix path.
+ *
+ * Useful when a system expects a unix path, but you need to be able to run it on non unix systems.
+ *
+ * @see absoluteUnixPath
+ */
+val File.unixPath: String
+  get() = path.replace("\\", "/")
+
+/**
+ * The [absolutePath][File.getAbsolutePath] represented as a qualified unix path.
+ *
+ * Useful when a system expects a unix path, but you need to be able to run it on non unix systems.
+ *
+ * @see unixPath
+ */
+val File.absoluteUnixPath: String
+  get() = absolutePath.replace("\\", "/")