Zip File System Provider

ZipUtils.kt

/**
 * Kotlin version: 1.3.61
 * JVM target: 1.8
 * @param source the path to the file to copy
 * @param target the path to the target file
 * @param env a map of provider specific properties to configure the file system
 *        @see https://docs.oracle.com/javase/8/docs/technotes/guides/io/fsp/zipfilesystemprovider.html
 */
fun archive(
    source: Path,
    target: Path,
    env: Map<String, String> = mapOf("create" to "true", "encoding" to "UTF-8")
) {
    val targetFile = target.toFile().let {
        if (it.isDirectory) {
            // target is directory, should generate the file name with source
            return@let File(it, "${source.fileName}.zip")
        }
        return@let it
    }
    // create the new zip file system
    val zipUri = URI.create("jar:file:${targetFile.absolutePath}")
    FileSystems.newFileSystem(zipUri, env).use { fs ->
        traverse(fs, source.parent, source)
    }
}

/**
 * Archive file recursively
 */
private fun traverse(fs: FileSystem, root: Path, source: Path) {
    val relativePath = root.relativize(source)
    val target = fs.getPath(relativePath.toString())
    Files.copy(source, target, StandardCopyOption.REPLACE_EXISTING)
    source.toFile().takeIf {
        it.isDirectory
    }?.listFiles()?.forEach { child ->
        traverse(fs, root, child.toPath())
    }
}