From 0fd55565d3204fbb152166c2186ba70f6cf38222 Mon Sep 17 00:00:00 2001 From: Bobby Rong Date: Fri, 23 Apr 2021 12:46:02 +0800 Subject: doc/contributing/*.xml: Convert to markdown --- doc/contributing/quick-start.chapter.md | 77 +++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 doc/contributing/quick-start.chapter.md (limited to 'doc/contributing/quick-start.chapter.md') diff --git a/doc/contributing/quick-start.chapter.md b/doc/contributing/quick-start.chapter.md new file mode 100644 index 000000000000..85c3897221ee --- /dev/null +++ b/doc/contributing/quick-start.chapter.md @@ -0,0 +1,77 @@ +# Quick Start to Adding a Package {#chap-quick-start} + +To add a package to Nixpkgs: + +1. Checkout the Nixpkgs source tree: + + ```ShellSession + $ git clone https://github.com/NixOS/nixpkgs + $ cd nixpkgs + ``` + +2. Find a good place in the Nixpkgs tree to add the Nix expression for your package. For instance, a library package typically goes into `pkgs/development/libraries/pkgname`, while a web browser goes into `pkgs/applications/networking/browsers/pkgname`. See for some hints on the tree organisation. Create a directory for your package, e.g. + + ```ShellSession + $ mkdir pkgs/development/libraries/libfoo + ``` + +3. In the package directory, create a Nix expression — a piece of code that describes how to build the package. In this case, it should be a _function_ that is called with the package dependencies as arguments, and returns a build of the package in the Nix store. The expression should usually be called `default.nix`. + + ```ShellSession + $ emacs pkgs/development/libraries/libfoo/default.nix + $ git add pkgs/development/libraries/libfoo/default.nix + ``` + + You can have a look at the existing Nix expressions under `pkgs/` to see how it’s done. Here are some good ones: + + - GNU Hello: [`pkgs/applications/misc/hello/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/misc/hello/default.nix). Trivial package, which specifies some `meta` attributes which is good practice. + + - GNU cpio: [`pkgs/tools/archivers/cpio/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/tools/archivers/cpio/default.nix). Also a simple package. The generic builder in `stdenv` does everything for you. It has no dependencies beyond `stdenv`. + + - GNU Multiple Precision arithmetic library (GMP): [`pkgs/development/libraries/gmp/5.1.x.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/libraries/gmp/5.1.x.nix). Also done by the generic builder, but has a dependency on `m4`. + + - Pan, a GTK-based newsreader: [`pkgs/applications/networking/newsreaders/pan/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/networking/newsreaders/pan/default.nix). Has an optional dependency on `gtkspell`, which is only built if `spellCheck` is `true`. + + - Apache HTTPD: [`pkgs/servers/http/apache-httpd/2.4.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/servers/http/apache-httpd/2.4.nix). A bunch of optional features, variable substitutions in the configure flags, a post-install hook, and miscellaneous hackery. + + - Thunderbird: [`pkgs/applications/networking/mailreaders/thunderbird/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/networking/mailreaders/thunderbird/default.nix). Lots of dependencies. + + - JDiskReport, a Java utility: [`pkgs/tools/misc/jdiskreport/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/tools/misc/jdiskreport/default.nix). Nixpkgs doesn’t have a decent `stdenv` for Java yet so this is pretty ad-hoc. + + - XML::Simple, a Perl module: [`pkgs/top-level/perl-packages.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/top-level/perl-packages.nix) (search for the `XMLSimple` attribute). Most Perl modules are so simple to build that they are defined directly in `perl-packages.nix`; no need to make a separate file for them. + + - Adobe Reader: [`pkgs/applications/misc/adobe-reader/default.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/misc/adobe-reader/default.nix). Shows how binary-only packages can be supported. In particular the [builder](https://github.com/NixOS/nixpkgs/blob/master/pkgs/applications/misc/adobe-reader/builder.sh) uses `patchelf` to set the RUNPATH and ELF interpreter of the executables so that the right libraries are found at runtime. + + Some notes: + + - All [`meta`](#chap-meta) attributes are optional, but it’s still a good idea to provide at least the `description`, `homepage` and [`license`](#sec-meta-license). + + - You can use `nix-prefetch-url url` to get the SHA-256 hash of source distributions. There are similar commands as `nix-prefetch-git` and `nix-prefetch-hg` available in `nix-prefetch-scripts` package. + + - A list of schemes for `mirror://` URLs can be found in [`pkgs/build-support/fetchurl/mirrors.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/build-support/fetchurl/mirrors.nix). + + The exact syntax and semantics of the Nix expression language, including the built-in function, are described in the Nix manual in the [chapter on writing Nix expressions](https://hydra.nixos.org/job/nix/trunk/tarball/latest/download-by-type/doc/manual/#chap-writing-nix-expressions). + +4. Add a call to the function defined in the previous step to [`pkgs/top-level/all-packages.nix`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/top-level/all-packages.nix) with some descriptive name for the variable, e.g. `libfoo`. + + ```ShellSession + $ emacs pkgs/top-level/all-packages.nix + ``` + + The attributes in that file are sorted by category (like “Development / Libraries”) that more-or-less correspond to the directory structure of Nixpkgs, and then by attribute name. + +5. To test whether the package builds, run the following command from the root of the nixpkgs source tree: + + ```ShellSession + $ nix-build -A libfoo + ``` + + where `libfoo` should be the variable name defined in the previous step. You may want to add the flag `-K` to keep the temporary build directory in case something fails. If the build succeeds, a symlink `./result` to the package in the Nix store is created. + +6. If you want to install the package into your profile (optional), do + + ```ShellSession + $ nix-env -f . -iA libfoo + ``` + +7. Optionally commit the new package and open a pull request [to nixpkgs](https://github.com/NixOS/nixpkgs/pulls), or use [the Patches category](https://discourse.nixos.org/t/about-the-patches-category/477) on Discourse for sending a patch without a GitHub account. -- cgit v1.2.3