wildsoul / melpa

Scripts for building Emacs packages from Version Control

MELPA

MELPA is a growing collection of package.el-compatible Emacs Lisp packages built automatically on our server from the upstream source code using simple recipes. (Think of it as a server-side version of el-get, or even homebrew.)

Packages are updated at intervals throughout the day.

To browse available packages, check out the archive index page.

Adding packages is as simple as submitting a pull request; read on for details.

Table of Contents

• Usage
• Contributing
• Recipe Format
• Build Scripts
• API
• MELPA Package
• About

Usage

To use the MELPA repository, add it to package-archives after (require 'package) and before the call to package-initialize in your init.el file.

(add-to-list 'package-archives
             '("melpa" . "http://melpa.milkbox.net/packages/") t)

In Emacs < 24, you'll also need to explicitly include the GNU ELPA archive, which provides important compatibility libraries like cl-lib:

(when (< emacs-major-version 24)
  (add-to-list 'package-archives '("gnu" . "http://elpa.gnu.org/packages/")))

A complete minimal example for MELPA,

(require 'package)
(add-to-list 'package-archives
             '("melpa" . "http://melpa.milkbox.net/packages/") t)
(when (< emacs-major-version 24)
  (add-to-list 'package-archives '("gnu" . "http://elpa.gnu.org/packages/")))
(package-initialize)

Since package.el doesn't allow locking packages to certain version, MELPA packages will override those available from any other package source, so we also provide a package melpa.el which contains code to allow restricting packages to specific repositories. This allows someone to blacklist packages that come from a specific repository, or blacklist all packages from a repository and only whitelist certain packages.

See the MELPA Package section below if you think you might want that.

Contributing New Recipes

New recipe submissions should adhere to the following guidelines,

• One pull request per recipe. You can create multiple branches and create a pull request for each branch.

• Upstream source must be stored in an authoritative SCM repository. Emacswiki recipes are discouraged but can be accepted.

• Packages should be built from the official package repository. Forks of the official repository will not be accepted except in extreme circumstances.

• The package name should match the name of the feature provided. See the package function for more information.

• Packages should adhere to the package.el format as specified by (info "(elisp) Packaging"). More information on this format is provided by the marmalade package manual.

• Recipes should try to minimize the size of the resulting package by specifying only files relevant to the package. See the Recipe Format section for more information on specifying package files.

Expediting Recipe Reviews

Because we care about the quality of packages that are part of MELPA we review all submissions. The following steps can help us with this process and expedite the recipe review process,

• Include the following information in the pull request:

  • A brief summary of what the package does.

  • Your association with the package (e.g., are you the maintainer? have you contributed? do you just like the package a lot?).

  • A direct link to the package repository.

  • Relevant communications with the package maintainer (e.g., package.el compatibility changes that you have submitted).

• Test that the package builds properly via make recipes/<recipe>.

• Test that the package installs properly via package-install-file.

Testing

Let <NAME> denote the name of the recipe to submit.

1. Fork the MELPA repository.

2. Add your new file under the directory specified by package-build-recipes-dir (default: recipes/ directory where package-build was loaded).

3. Confirm your package built properly by running

    make recipes/<NAME>
   

(Be sure that the emacs on your path is at least version 23, or set $EMACS to the location of a suitable binary.)

4. Install the file you built by running package-install-file from within Emacs and specifying the newly built package in the directory specified by package-build-archive-dir (default: packages/ directory where package-build was loaded).

Submitting

After verifying the entry works properly please open a pull request on Github. Consider the hub command-line utility by defunkt which helps simplify this process.

Recipe Format

Packages are specified by files in the recipes directory. You can contribute a new package by adding a new file under recipes using the following form ([...] denotes optional or conditional values),

(<package-name>
 :fetcher [git|github|bzr|hg|darcs|svn|cvs|wiki]
 [:url "<repo url>"]
 [:repo "github-user/repo-name"]
 [:module "cvs-module"]
 [:files ("<file1>" ...)])

• package-name a lisp symbol that has the same name as the package being specified.

• :fetcher (one of git, github, bzr, hg, darcs, svn, cvs, wiki) specifies the type of repository that :url points to. Right now package-build supports git, github, bazaar (bzr), mercurial (hg), subversion (svn), cvs, darcs, and Emacs Wiki (wiki) as possible mechanisms for checking out the repository.

  package-build uses the corresponding application to update files before building the package. In the case of the github fetcher, use :repo instead of :url; the git URL will then be deduced.

  The Emacs Wiki fetcher gets the latest version of the package from http://www.emacswiki.org/emacs/download/<NAME>.el where NAME is the package name. Note that the :url property is not needed for the wiki engine unless the name of the package file on the EmacsWiki differs from the package name being built.

• :url specifies the URL of the version control repository. required for the git, bzr, hg, darcs, svn and cvs fetchers.

• :repo specifies the github repository and is of the form github-user/repo-name. required for the github fetcher.

• :commit specifies the commit or branch of the git repo to checkout. The value will be passed to git reset in a repo where upstream is the original repository. Can therefore be either a sha, if pointing at a specific commit, or a branch (prefixed with "origin/"). Only used by the git and github fetchers.

• :module specifies the module of a CVS repository to check out. Defaults to to package-name. Only used with :fetcher cvs, and otherwise ignored.

• :files [default: (*.el *.info dir)] optional property specifying the elisp and info files used to build the package. Automatically populated by matching all .el, .info and dir files in the root of the repository.

  This option is necessary when there are multiple packages in the repository and thus the package should only be built from a subset of .el files. For example, elisp test files should not normally be packaged. Any file specified at any path in the repository is copied to the root of the package. More complex options are available, submit an Issue if the specified package requires more complex file specification.

Example: Single File Repository

ido-ubiquitous is a repository that contains two files:

• README.md
• ido-ubiquitous.el

Since there is only one .el file, this package only needs the :url and :fetcher specified,

(ido-ubiquitous
 :url "https://github.com/DarwinAwardWinner/ido-ubiquitous.git"
 :fetcher git)

Example: Multiple Packages in one Repository

The emacs-starter-kit contains the starter-kit package along with extra packages in the modules directory; starter-kit-bindings, starter-kit-lisp, etc.

(starter-kit
 :url "https://github.com/technomancy/emacs-starter-kit.git"
 :fetcher git)
(starter-kit-bindings
 :url "https://github.com/technomancy/emacs-starter-kit.git"
 :fetcher git
 :files ("modules/starter-kit-bindings.el"))

Notice that :files is not specified for starter-kit since package-build will automatically add all .el files in the root directory of the repository. The starter-kit-bindings repository is contained in the modules/ subdirectory and thus needs the packages files specified explicitly.

Example: Multiple Files in Multiple Directories

There are special cases when we need There are special cases where creation of the package comes from many different sub-directories in the repository and the destination sub-directories need to be explicitly set.

Consider the flymake-perlcritic recipe,

(flymake-perlcritic :repo "illusori/emacs-flymake-perlcritic"
                    :fetcher github
                    :files ("*.el" ("bin" "bin/flymake_perlcritic")))

which will result in a package structure of,

flymake-perlcritic-YYYMMDD
|-- bin
|   `-- flymake_perlcritic
|-- flymake-perlcritic-pkg.el
`-- flymake-perlcritic.el

Notice that specifying an entry in :files that is a list takes the first element to be the destination directory. These can be embedded further, such as the following---hypothetical---entry for :files,

("*.el" ("snippets"
         ("html-mode" "snippets/html-mode/*")
         ("python-mode" "snippets/python-mode/*")))

which would result in a package with *.el in something like,

package-YYYYMMDD
|-- snippets
|   |-- html-mode
|   |   |-- div
|   |   `-- html
|   `-- python-mode
|       |-- for
|       `-- main
`-- package.el

But a better solution, given that we probably want to copy the entire snippets directory to the root of the package, we could just specify that directory. Consider the pony-mode recipe,

(pony-mode
 :repo "davidmiller/pony-mode"
 :fetcher github
 :files ("src/*.el" "snippets"))

which generates the package,

pony-mode-YYYYMMDD
|-- pony-mode-pkg.el
|-- pony-mode.el
|-- pony-tpl.el
`-- snippets
    |-- html-mode
    |   |-- bl
    |   |-- ex
    |   |-- for
    |   |-- if
    |   |-- loa
    |   |-- sup
    |   |-- testc
    |   `-- {{
    `-- python-mode
        |-- auth-view
        |-- bn
        |-- model
        |-- modelform
        |-- render-to
        |-- testc
        `-- view

Build Scripts

Building MELPA is all based around using the Makefile included in the root repository directory. Described below are the actions that accepted by the Makefile.

• all -- Builds all packages under the recipes/ directory and compiles the index.html file for the melpa website.

• recipes/<NAME> -- Build individual recipe <NAME>. Built packages are put in the packages/ folder with version corresponding to the newest HEAD revision available; given according to the %Y%m%d format.

• json -- build all JSON files.

• archive.json -- construct the archive.json file that will contain a JSON object of all compiled packages.

• recipes.json -- construct the recipes.json file containing a JSON object of all packages available for building.

• clean -- clean everything.

• html -- build index.html.

• clean-working -- remove all repositories that have been checked out to the working/ directory.

• clean-packages -- remove all compiled packages from the packages directory.

• clean-json -- remove all JSON files.

Note that these scripts require an Emacs with package.el installed, such as Emacs 24. If you have an older version of Emacs, you can get a suitable package.el here.

API

All repository code is contained in the package-build.el.

Functions

• (package-build-all) : build packages for all recipes in the directory specified by package-build-recipes-dir.

• (package-build-archive NAME) : interactive elisp function to build a single archive. NAME is a symbol for the package to be built. Packages are staged in the directory specified by package-build-working-dir and built packages are placed in the directory specified by package-build-archive-dir. Packages are versioned based on the most recent commit date to package files based on commits to upstream package repository. For multi-file packages, the file <NAME>-pkg.el is automatically generated and contains description, version, and requires information determined by searching <NAME>-pkg.el, <NAME>.el, and <NAME>-pkg.el.in, if they exist in the repository.

Variables

• package-build-working-dir : Staging area containing package repositories and package directories being built.

• package-build-archive-dir : Location to store archive-contents and any built packages.

• package-build-recipes-dir : Directory containing MELPA compatible recipes. See Recipe Format section for more details.

Configuration

Packages end up in the packages/ directory by default. This can be configured using the package-build-archive-dir variable.

Repositories are checked out to the working/ directory by default. This can be configured using the package-build-working-dir variable.

MELPA Package

The melpa.el package---available in MELPA--allows creating a whitelist or blacklist of packages for a specific repository. This allows for disabling all packages from a specific repository and only enabling certain packages, or simply blacklist a certain subset of packages.

Configuring

By default there are two variables that can be customized to specify which packages will be enabled (whitelist packages only) or excluded (blacklist of packages)

• package-archive-enable-alist : Optional Alist of enabled packages used by package-filter. The format is (ARCHIVE . PACKAGE ...), where ARCHIVE is a string matching an archive name in package-archives, PACKAGE is a symbol of a package in ARCHIVE to enable. If no ARCHIVE exists in the alist, all packages are enabled.

  If no ARCHIVE exists in the alist, all packages are enabled.

• package-archive-exclude-alist : Alist of packages excluded by package-filter. The format is (ARCHIVE . PACKAGE ...), where ARCHIVE is a string matching an archive name in package-archives, PACKAGE is a symbol of a package in that archive to exclude. Any specified package is excluded regardless of the value of package-archive-enable-alist

  If a particular ARCHIVE has an entry in package-archive-enable-alist then only packages

Manual Installation

You can install the package manually by pasting this into your *scratch* buffer and evaluating it.

(progn
  (switch-to-buffer
   (url-retrieve-synchronously
    "https://raw.github.com/milkypostman/melpa/master/melpa.el"))
  (package-install-from-buffer  (package-buffer-info) 'single))

About

MELPA is Milkypostman's ELPA or Milkypostman's Experimental Lisp Package Archive if you're not into the whole brevity thing.