build.gradle

// Copyright (c) Facebook, Inc. and its affiliates.
//
// This source code is licensed under the MIT license found in the
// LICENSE file in the root directory of this source tree.

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    ext {
        minSdkVersion = 15
        targetSdkVersion = 28
        compileSdkVersion = 28
        kotlinVersion = '1.6.10'
        buildToolsVersion = '30.0.2'
        sourceCompatibilityVersion = JavaVersion.VERSION_1_7
        targetCompatibilityVersion = JavaVersion.VERSION_1_7
    }
    repositories {
        google()
        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:7.0.4'
        classpath 'com.vanniktech:gradle-maven-publish-plugin:0.18.0'
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
    }
}

plugins {
    id 'de.undercouch.download' version '3.4.3'
}

subprojects {
    repositories {
        google()
        mavenLocal()
        mavenCentral()
    }
}

ext.isRelease = { ['publish', 'publishToMaven'].any { gradle.startParameter.taskNames.contains(it) } }

ext.deps = [
        // Android Support Libraries
        supportAppCompat: 'androidx.appcompat:appcompat:1.0.0',
        supportTestRunner: 'androidx.test:runner:1.1.0',
        supportTestRules: 'androidx.test:rules:1.1.0',
        supportMultidex: 'androidx.multidex:multidex:2.0.1',

        // Annotations
        jsr305: 'com.google.code.findbugs:jsr305:3.0.1',

        // First-party
        soloader: 'com.facebook.soloader:soloader:0.10.4',

        // Third-party
        dexmaker: 'com.google.dexmaker:dexmaker:1.2',
        dexmakerMockito: 'com.google.dexmaker:dexmaker-mockito:1.2',
        festAssert: 'org.easytesting:fest-assert-core:2.0M10',
        junit: 'junit:junit:4.12',
        kotlinAndroidKtx: 'androidx.core:core-ktx:1.0.1',
        kotlinJdk: "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlinVersion",
        mockitoCore: 'org.mockito:mockito-core:1.10.19',
        robolectric: 'org.robolectric:robolectric:3.0',
]

//
// Custom plugin to download external native libraries and merge them with our
// overrides and custom configurations.
//

apply plugin: 'de.undercouch.download'
import de.undercouch.gradle.tasks.download.Download

class SpectrumDownloadAndMergeExtension {
    String externalSourceUri
    String externalSourceInclude
    String overrideInclude

    // The files matching pattern and action are used for replacing tokens
    // in the imported third-party files. E.g. to emulate an "./configure" call
    String filesMatchingPattern
    Action<? super FileCopyDetails> filesMatchingAction

    /**
     * The cache revision is used to avoid invalidating the gradle cache information
     * of external files copied from other destinations. Such invalidation (e.g.
     * updating the timestamp causes the entire native code to be rebuild). And
     * we care about developer experience.
     *
     * As a consequence, the cache revision needs to be updated when there's any
     * change regarding the external dependency (either the downloaded version
     * of the override)
     */
    Integer cacheRevision
}

class SpectrumDownloadAndMergePlugin implements Plugin<Project> {

    final def getDownloadFileName = { final URL src ->
        final def i = src.file.lastIndexOf('/')
        return src.file.substring(i + 1)
    }

    boolean isCacheOutOfDate(
            final File revisionFile,
            final Integer revisionNumber,
            final String projectName = null) {
        boolean outOfDate = false
        if (revisionNumber == null || !revisionFile.exists()) {
            outOfDate = true
        } else {
            final def content = revisionFile.text
            outOfDate = !content.isInteger() || content as Integer != revisionNumber
        }

        if (projectName != null) {
            println "External library '${projectName}' is " +
                    (outOfDate ? "out-of-date, preparing..." : "up-to-date")
        }
        return outOfDate
    }

    void apply(Project project) {
        final def extension = project.extensions.create(
            'downloadAndMergeNativeLibrary',
            SpectrumDownloadAndMergeExtension)

        final def downloadDir = new File("${project.getBuildDir()}/download")
        final def extractionDir = new File("${project.getBuildDir()}/downloadExtracted")
        final def mergeDir = new File("${project.getProjectDir()}/merge/${project.name}")
        final def overrideDir = new File("${project.getProjectDir()}/override")
        final def revisionFile = new File("${project.getBuildDir()}/spectrum_cache_revision.txt")

        // extensions are only properly instantiated after evaluation
        project.afterEvaluate {
            project.task('createNativeDepsDirectories') {
                downloadDir.mkdirs()
                extractionDir.mkdirs()
                mergeDir.mkdirs()
            }

            project.task('cleanNativeLibrary', type: Delete) {
                delete mergeDir
                delete extractionDir
            }

            project.task(
                    'downloadNativeLibrarySource',
                    dependsOn: 'createNativeDepsDirectories',
                    type: Download) {
                src extension.externalSourceUri
                onlyIfNewer true
                overwrite false
                dest new File(downloadDir, getDownloadFileName(src))
            }

            project.task(
                    'extractNativeLibrarySource',
                    dependsOn: 'downloadNativeLibrarySource',
                    type: Copy) {
                from project.tarTree(
                    project.tasks.getByName('downloadNativeLibrarySource').dest)
                include '**'
                includeEmptyDirs = false
                into extractionDir
            }

            project.task(
                    'copyExternalSources',
                    dependsOn: 'extractNativeLibrarySource',
                    type: Copy) {
                onlyIf {
                  isCacheOutOfDate(revisionFile, extension.cacheRevision)
                }
                from extractionDir
                include extension.externalSourceInclude
                includeEmptyDirs = false
                if (extension.filesMatchingPattern != null) {
                    filesMatching(extension.filesMatchingPattern, extension.filesMatchingAction)
                }
                into mergeDir
            }

            project.task(
                    'copyOverrideSources',
                    dependsOn: 'copyExternalSources',
                    type: Copy) {
                onlyIf {
                  isCacheOutOfDate(revisionFile, extension.cacheRevision)
                }
                from overrideDir
                include extension.overrideInclude
                includeEmptyDirs = false
                into mergeDir
            }

            project.task(
                    'prepareNativeLibrary',
                    dependsOn: 'copyOverrideSources') {
                onlyIf {
                  isCacheOutOfDate(revisionFile, extension.cacheRevision, project.name)
                }
                doLast {
                  println "Prepared library '${project.name}' in folder ${mergeDir}"
                  revisionFile.text = extension.cacheRevision.toString()
                }
            }
        }
    }
}

ext.SpectrumDownloadAndMergePlugin = SpectrumDownloadAndMergePlugin