README

Composer plugin to isolate project dependencies by prefixing their namespace.

How it Works

This plugin prefixes all vendor namespaces with a chosen value. This includes all declared namespaces, use statements, fully qualified references, and most string values that reference the namespace.

All vendor code and composer autoload mappings are updated to reference the prefixed namespace.

What it does not do

It will not touch any code in your project. It only affects code in the vendor directory, and it only affects code referencing the affected namespaces. You must update all references in your code yourself if you apply this to an existing project.

Why use it

This plugin allows you to run two projects that utilize composer dependencies in the same runtime, without worrying about conflicting dependencies. The most common example is in a WordPress environment, where all plugins execute in the same runtime, and may rely on the same composer dependencies. Each project utilizing the plugin can't conflict with any other project unless the vendor code is not namespaced (in which case there aren't many options...).

Known Limitations

• It doesn't replace function definitions and calls in the global namespace. Any definitions and calls to global functions will remain in the global namespace after the transformation.

Usage

Using the plugin is straightforward. Install the plugin by requiring it in your project: composer require and/isolate-composer.

Configure the plugin by adding the following to your composer.json:

"config" : {
    "isolate": {
      "prefix": "Your\\Prefix\\Here\\",
      "excludelist": [],
      "autorun": false,
      "require-dev": false,
      "replacements" : {}
    }
}

The only required value is the prefix.

After you have configured the plugin, run the isolation:

composer isolate
composer dump

Your vendor code is now prefixed!

Be sure to dump after you isolate, or your autoload mappings will be incorrect!

Configuration

prefix

This is the value that will be prepended to all vendor namespaces. It should be a valid namespace, and should be unique to your project. I recommend you don't use your main project namespace, or at least add \\Vendor to the end.

exludelist

This is a list of packages you don't want to prefix. Matching packages will not be scanned for namespaces, but will still have code rewritten if it contains namespaces from other non-excluded packages.

autorun

Setting this value to true automatically runs the isolation process before every dump.

require-dev

By default, only require packages are scanned for namespaces, and require-dev packages are ignored (as above, they will still have code rewritten if they contain namespaces from other packages).

Setting this value to true includes the require-dev packages in the scan, and any found namespaces will be prefixed.

replacements

This is a place for manually fixing things in the vendor code that either were not detected and replaced, or replaced when they should not have been.

After each file has been parsed and rewritten, if there is an entry in the replacements list, it will do a string replace on the file.

String replacements should be idempotent, or things will break on multiple executions.

The syntax is:

"replacements" : {
    "path/relative/to/vendor/root/file.php" : {
        "search" : "replace",
        "search" : "replace",
    },
    "path/relative/to/vendor/root/file.php" : {
            "search" : "replace",
            "search" : "replace",
        }
}

Credits

Created and maintaned by XWP as a fork of and/composer-isolation.