# Basic Archive Processing

# Packing An Archive File

The following code packs the TAR.GZ file archive.tar.gz from the directory directory. It uses the CommonsCompress facade for accessing the TAR file format and transforming it to TAR.GZ using Apache Commons Compress. It also uses the BIOS facade for accessing directories like archive files and copying them:

import static global.namespace.fun.io.commons.compress.CommonsCompress.gzip; // from module `fun-io-commons-compress`
import static global.namespace.fun.io.commons.compress.CommonsCompress.tar;
import static global.namespace.fun.io.bios.BIOS.copy;                        // from module `fun-io-bios`
import static global.namespace.fun.io.bios.BIOS.directory;
import static global.namespace.fun.io.bios.BIOS.file;

class Scratch {
    public static void main(String[] args) throws Exception {
        copy(directory("directory"), tar(file("archive.tar.gz").map(gzip())));
    }
}

# Unpacking An Archive File

The following code is the inverse of the previous operation:

import static global.namespace.fun.io.commons.compress.CommonsCompress.gzip;
import static global.namespace.fun.io.commons.compress.CommonsCompress.tar;
import static global.namespace.fun.io.bios.BIOS.copy;
import static global.namespace.fun.io.bios.BIOS.directory;
import static global.namespace.fun.io.bios.BIOS.file;

class Scratch {
    public static void main(String[] args) throws Exception {
        copy(tar(file("archive.tar.gz").map(gzip())), directory("directory"));
    }
}

# Transforming An Archive File

The following code transforms the TAR.GZ file archive.tar.gz to the ZIP file archive.zip. When calling the copy method, all archive entries are directly "streamed" from the input archive to the output archive without buffering them in a temporary file, so this operation is fast and space efficient:

import static global.namespace.fun.io.commons.compress.CommonsCompress.gzip;
import static global.namespace.fun.io.commons.compress.CommonsCompress.tar;
import static global.namespace.fun.io.commons.compress.CommonsCompress.zip;
import static global.namespace.fun.io.bios.BIOS.copy;
import static global.namespace.fun.io.bios.BIOS.file;

class Scratch {
    public static void main(String[] args) throws Exception {
        copy(tar(file("archive.tar.gz").map(gzip())), zip("archive.zip"));
    }
}

# Working with S3 Buckets

Fun I/O treats S3 buckets like archive files. This feature enables you to copy and transform data between an S3 bucket (with an optional key prefix) and any other supported archive file, directory or S3 bucket (with an optional key prefix).

Fun I/O provides two modules for accessing S3:

Fun I/O AWS SDK1 (alias fun-io-aws-sdk1) depends on the Amazon SDK for Java and provides the package global.namespace.fun.io.aws.sdk1.
Fun I/O AWS SDK2 (alias fun-io-aws-sdk2) depends on the Amazon SDK for Java 2 and provides the package global.namespace.fun.io.aws.sdk2.

Both packages provide a facade class named AWS with identical behavior.

The following code uses Fun I/O AWS SDK1 to "unpack" the TAR.GZ file archive.tgz to the S3 bucket bucket with the key prefix archive/:

import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;

import static global.namespace.fun.io.aws.sdk1.AWS.s3; // from module `fun-io-aws-sdk1`
import static global.namespace.fun.io.bios.BIOS.copy;
import static global.namespace.fun.io.bios.BIOS.file;
import static global.namespace.fun.io.commons.compress.CommonsCompress.gzip;
import static global.namespace.fun.io.commons.compress.CommonsCompress.tar;

class Scratch {
    public static void main(String[] args) throws Exception {
        AmazonS3 client = AmazonS3ClientBuilder.defaultClient();
        copy(tar(file("archive.tgz").map(gzip())), s3(client, "bucket", "archive/"));
    }
}

TIP

If provided, the key prefix must be either empty or a normalized path which ends with a /. Absolute paths or referencing parent directories is not allowed. For example, the following key prefixes are invalid:

path doesn't end with a /.
/path/ is an absolute path.
./path/ is not in normalized form.
../path/ references the parent directory.