Create a package

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This page explains how to create packages in postmarketOS, so they can be built with the usual pmbootstrap build hello-world.

Quick start

Create a template for a new package called mynewpackage in aports/main:

$ pmbootstrap newapkbuild mynewpackage
[21:34:27] Create /home/user/code/pmbootstrap/aports/main/mynewpackage
[21:34:27] Done

We pass the arguments to newapkbuild from Alpine, which has lots of parameters to quickly customize the templates it generates. It is even possible to just specify the URL and let it download the tarball and automatically recognize the build system, package name and version:

$ pmbootstrap newapkbuild "https://github.com/alpinelinux/abuild/archive/v3.1.0.tar.gz"

For reference, see the full help output:

$ pmbootstrap newapkbuild -h
usage: pmbootstrap newapkbuild [-h] [--folder FOLDER] [-n PKGNAME]
                               [-d PKGDESC] [-l LICENSE] [-u URL]
                               [-a | -C | -m | -p | -y] [-s] [-c] [-f]
                               PKGNAME[-PKGVER] | SRCURL

positional arguments:
  PKGNAME[-PKGVER] | SRCURL
                        set either the package name (optionally with the
                        PKGVER at the end, e.g. 'hello-world-1.0') or the
                        download link to the source archive

optional arguments:
  -h, --help            show this help message and exit
  --folder FOLDER       set postmarketOS aports folder (default: main)
  -n PKGNAME            set package name (only use with SRCURL)
  -d PKGDESC            set package description
  -l LICENSE            set package license identifier from
                        <https://spdx.org/licenses/>
  -u URL                set package URL
  -a                    create autotools package (use ./configure ...)
  -C                    create CMake package (assume cmake/ is there)
  -m                    create meson package (assume meson.build is there)
  -p                    create perl package (assume Makefile.PL is there)
  -y                    create python package (assume setup.py is there)
  -s                    use sourceforge source URL
  -c                    copy a sample init.d, conf.d and install script
  -f                    force even if directory already exists

Remember to update the checksums after changing the sources:

$ pmbootstrap checksum hello-world

General information

This section is hard to read, feel free to rewrite.
  • Please read this section from our upstream friends wiki (which we should also extend and improve)
  • Please always package the latest version of a software (unless it is impossible because of software that depends on it, but try to avoid that!)
  • Please do not copy maintainers/contributors from the other packages to your new ports (so they won't get annoyed by questions for pmOS/Alpine packages!). Instead please credit them in the commit messages (maybe with a link to the original build recipe)
  • Alpine Linux uses musl as libc, not glibc. Never add glibc as dependency.
  • Alpine uses busybox' sh for building packages. Do not use bash specific features.
  • Manpages and other documentation goes into an extra -doc package in Alpine, and abuild will complain if the main package contains them. The solution is to add this: subpackages="$pkgname-doc" (more info)
  • You can look up the exact meaning of every variable and function in the APKBUILD Reference
  • Set up the git hook from the development guide article to automatically verify checksums in your APKBUILDs and therefore making your life easier
  • How to create a patch when packaging software

Beware of legacy APKBUILDs

Alpine's program to build packages, abuild evolves constantly. But the APKBUILDs sometimes lack behind. Some APKBUILDs still have the following, which is unnecessary:

  • || return 1 statements after every line (e.g. make || return 1 is not needed anymore, use make instead)
  • a custom prepare() function that does nothing but apply patches (more information))
  • not using the builddir variable to point to the extracted source location (usually: builddir="$srcdir/$pkgname-$pkgver")

Packaging git commits

Only package git commits when necessary. Stable releases are preferred. Consider asking upstream to tag releases.

  • pkgver: We use the following format: $lastrelease_gitYYYYMMDD, e.g. 1.0_git20171101 (that makes it easy to see how old the commit is and apk is able to upgrade the package properly when the next release, e.g. 1.1, comes out)
  • Save the git commit in a variable _commit=.... and use it throughout the APKBUILD (e.g. in the builddir), so it's easy to update it.
  • The source should be saved with the $_commit in the filename. For GitHub links, this means:
 source="$pkgname-$_commit.tar.gz::https://github.com/ORG/NAME/archive/$_commit.tar.gz"

When should pkgver/pkgrel get increased?

Whenever you update a package, it must have a new version. A version consists of $pkgver-r$pkgrel. The APKBUILD_Reference says:

  • pkgver: The version of the software being packaged.
  • pkgrel: Alpine/postmarketOS package release number. Starts at 0 (zero). Always increment pkgrel when making updates to an aport; reset pkgrel to 0 (zero) when incrementing pkgver.

Special cases, where this is not so obvious:

  • linux-* packages: We always set the pkgver to the kernel version number and only increase it when the kernel source code has a new version number. All kernel config changes only increase the pkgrel number. In the case, that the linux kernel sources need to be updated, but the kernel version was not changed (Android kernel forks often do this), we can add a _gitYYYYMMDD suffix (see "Packaging git commits" above).
  • device-* packages: This was not done consistently in the past, but it makes sense to update the pkgver when anything but the APKBUILD was changed. Because that is essentially the version of the software being packaged.

Outdated config.sub/config.guess from autotools

In case the config.sub or config.guess are outdated, change the APKBUILD's prepare block to the following:

prepare() {
	default_prepare
	update_config_sub
	update_config_guess
}

Porting packages from Arch Linux

Arch Linux' PKBUILD format is similar to APKBUILD of Alpine. If you don't know how to package a new program, check out how Arch does it.

Find the package

Search here, click the package name, click on "Source Files" on the top right. A git repo with the PKGBUILD and all other files (such as patches) appears.

Differences between APKBUILDs and PKGBUILDs

  • APKBUILDs do not have the arrays from bash, use flat strings instead
  • There's no optdepends
  • -doc subpackages (see above)
  • APKBUILD has different options (!makeflags won't work, but it has !strip and !check)