1/*
2 * Copyright 2018 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package androidx.build
18
19import com.android.build.gradle.LibraryExtension
20import org.gradle.api.DefaultTask
21import org.gradle.api.Project
22import org.gradle.api.tasks.Input
23import org.gradle.api.tasks.OutputFile
24import org.gradle.api.tasks.TaskAction
25import java.io.File
26import java.io.PrintWriter
27
28/**
29 * Task that allows to write a version to a given output file.
30 */
31open class VersionFileWriterTask : DefaultTask() {
32    @get:Input
33    lateinit var version: String
34    @get:OutputFile
35    lateinit var outputFile: File
36
37    /**
38     * The main method for actually writing out the file.
39     */
40    @TaskAction
41    fun run() {
42        val writer = PrintWriter(outputFile)
43        writer.println(version)
44        writer.close()
45    }
46
47    companion object {
48        val RESOURCE_DIRECTORY = "generatedResources"
49        val VERSION_FILE_PATH = RESOURCE_DIRECTORY + "/META-INF/%s_%s.version"
50
51        /**
52         * Sets up Android Library project to have a task that generates a version file.
53         * It must be called after [LibraryExtension] has been resolved.
54         *
55         * @param project an Android Library project.
56         */
57        fun setUpAndroidLibrary(project: Project, library: LibraryExtension) {
58            val group = project.properties["group"] as String
59            val artifactId = project.properties["name"] as String
60            val version = project.properties["version"] as String
61
62            // Add a java resource file to the library jar for version tracking purposes.
63            val artifactName = File(
64                    project.buildDir,
65                    String.format(VERSION_FILE_PATH, group, artifactId))
66
67            val writeVersionFile = project.tasks.create("writeVersionFile",
68                    VersionFileWriterTask::class.java)
69            writeVersionFile.version = version
70            writeVersionFile.outputFile = artifactName
71
72            library.libraryVariants.all {
73                it.processJavaResources.dependsOn(writeVersionFile)
74            }
75
76            val resources = library.sourceSets.getByName("main").resources
77            resources.srcDir(File(project.buildDir, RESOURCE_DIRECTORY))
78            if (!resources.includes.isEmpty()) {
79                val includes = resources.includes
80                includes.add("META-INF/*.version")
81                resources.setIncludes(includes)
82            }
83        }
84    }
85}
86