Working with PHAR Files: A Guide to Using the 'phar' Command (with examples)

The phar command is a powerful utility for developers working with PHP applications. It allows you to create, update, extract, and manage PHP archives, also known as PHAR files. PHAR files are a convenient way to distribute and deploy entire applications in a single file, including all necessary resources like scripts, images, and other media. The phar command accommodates a wide range of operations, including adding files, displaying contents, compressing, and signing PHAR files, making it an indispensable tool for those dealing with PHP distribution.

Use case 1: Add one or more files or directories to a PHAR file

Code:

phar add -f path/to/phar_file path/to/file_or_directory1 path/to/file_or_directory2

Motivation:

There are scenarios in which a developer might have multiple PHP scripts and resources that need to be bundled together for ease of distribution. For example, if you’re developing a PHP library or a complete web application that needs to be deployed on multiple servers or made available for download to your users, you would need to package all relevant files and folders into a single PHAR file.

Explanation:

• add: This command tells phar to add files to a PHAR archive.
• -f path/to/phar_file: The -f flag specifies the PHAR file you are working with.
• path/to/file_or_directory1, path/to/file_or_directory2: These are paths to the files or directories you want to add to the PHAR file.

Example Output:

The command will add the specified files to the PHAR archive and may output success messages for each file and directory added, like this:

Adding 'path/to/file_or_directory1' to 'path/to/phar_file'... Success
Adding 'path/to/file_or_directory2' to 'path/to/phar_file'... Success

Use case 2: Display the contents of a PHAR file

Code:

phar list -f path/to/phar_file

Motivation:

It is often important to have a clear understanding of what files are contained within a PHAR archive, especially when troubleshooting or when you are verifying the contents before deployment or distribution. By listing its contents, you can be certain that your PHAR file includes all necessary files and directories.

Explanation:

• list: The command that outputs a list of files contained within the PHAR archive.
• -f path/to/phar_file: Again, the -f flag specifies the PHAR file to list contents from.

Example Output:

The command returns a list of files and directories included in the PHAR archive:

Listing contents of 'path/to/phar_file':
- index.php
- lib/module.php
- assets/style.css

Use case 3: Delete the specified file or directory from a PHAR file

Code:

phar delete -f path/to/phar_file -e file_or_directory

Motivation:

If a developer needs to update a PHAR file by removing obsolete files or directories, the delete operation becomes necessary. This might be due to refactoring, cleanup, or replacing older resources with newer ones, ensuring the PHAR file contains only the relevant files.

Explanation:

• delete: The phar command used to remove a file or directory from the PHAR archive.
• -f path/to/phar_file: Specifies the PHAR file from which you want to delete a file or directory.
• -e file_or_directory: Identifies the exact file or directory to be deleted from the PHAR archive.

Example Output:

The command will remove the file from the PHAR archive and typically provide feedback:

Deleting 'file_or_directory' from 'path/to/phar_file'... Success

Use case 4: Compress or uncompress files and directories in a PHAR file

Code:

phar compress -f path/to/phar_file -c gzip

Motivation:

Compressing a PHAR archive can significantly reduce its size, making it easier to store and faster to transfer over the internet. This is particularly useful for web applications that require reduced bandwidth usage or platform distributions that aim for a compact deployment file size.

Explanation:

• compress: This command is used to compress or uncompress the PHAR file’s contents.
• -f path/to/phar_file: Indicates which PHAR file should be compressed.
• -c gzip: The -c flag specifies the algorithm to use for compression, such as gzip, bzip2, or none for no compression.

Example Output:

The command notifies you with compression status messages, like:

Compressing 'path/to/phar_file' using 'gzip'... Success

Use case 5: Get information about a PHAR file

Code:

phar info -f path/to/phar_file

Motivation:

Understanding the metadata and configuration of a PHAR file can be beneficial for debugging or reviewing the archive’s properties and ensuring it meets all your needs. Info command usage includes checking the stub, alias, or getting a general overview of the archive’s structure.

Explanation:

• info: The command used to display metadata about the PHAR file.
• -f path/to/phar_file: Specifies the PHAR file from which you want to retrieve information.

Example Output:

The output provides detailed information about the PHAR file, typically including its alias, size, compressed size, etc.:

PHAR Information for 'path/to/phar_file':
- Alias: myphar.phar
- File Count: 10
- Uncompressed Size: 540KB
- Compressed Size: 420KB
- Compression Type: gzip

Use case 6: Sign a PHAR file with a specific hash algorithm

Code:

phar sign -f path/to/phar_file -h sha256

Motivation:

Security is vital in software distribution. Signing a PHAR file ensures authenticity and integrity. By using a hash algorithm like SHA-256, you can protect the PHAR file against unauthorized modifications, instilling confidence in the end-users that the file hasn’t been tampered with.

Explanation:

• sign: The phar command to apply a digital signature to the PHAR file.
• -f path/to/phar_file: Identifies the PHAR file to sign.
• -h sha256: The -h flag specifies which hash algorithm to use, for example, sha256.

Example Output:

The command displays confirmation and details about the signing process:

Signing 'path/to/phar_file' with SHA-256... Success

Use case 7: Sign a PHAR file with an OpenSSL private key

Code:

phar sign -f path/to/phar_file -h openssl -y path/to/private_key

Motivation:

Using a private key and OpenSSL for signing adds an additional layer of security, providing stronger protection and traceability. This approach is suitable for secure software distribution, especially in enterprise settings where confidentiality and data integrity are paramount.

Explanation:

• sign: The command to conduct digital signing.
• -f path/to/phar_file: Specifies the target PHAR file.
• -h openssl: Indicates OpenSSL is the signing method.
• -y path/to/private_key: Points to the private key used for signing.

Example Output:

Successful execution shows messages confirming the signing:

Signing 'path/to/phar_file' with OpenSSL using the private key 'path/to/private_key'... Success

Use case 8: Display help and available hashing/compression algorithms

Code:

phar help

Motivation:

Developers new to the phar tool or those needing a refresher on available options and algorithms would benefit from the help feature. It’s crucial to be aware of all potential features and functionality that phar offers to efficiently manage PHAR archives.

Explanation:

• help: This command displays the help manual for phar, including usage instructions, options, and available hashing or compression algorithms.

Example Output:

Executing this command provides an overview of the tool’s usage:

Usage: phar [command] [options]
Commands:
  add       Add files to a PHAR archive.
  list      List files in a PHAR archive.
  ...
Hash Algorithms: md5, sha1, sha256, hash
Compression Algorithms: none, gzip, bzip2

Conclusion:

The phar command is an indispensable tool for PHP developers needing to manage, distribute, and secure their PHP applications as PHAR archives. Each use case is aimed at facilitating a crucial aspect of PHAR file management, providing developers with flexibility and peace of mind during software distribution and deployment.