Based on some feedback in #87094 and discussion with @fridh, this re-organizes
the onboarding tutorial in the Nixpkgs manual's python section, so that we start
with the simplest, most ad-hoc examples and work our way up. This progresses
from:
1. How to create an temporary python env at the cmdline, then
2. How to create a specific python env for a single script, then
3. How to create a specific python env for a project in a shell.nix, then
4. How to install a specific python env globally on the system or in a user profile.
Additionally, I've tried to standardize on some of the "best practice" ways of
doing things:
1. Instead of saying that this command style is "supported but strongly not
discouraged", I've just deleted it to avoid confusion.
Bad: nix-shell -p python38Packages.numpy python38Packages.toolz
Good: nix-shell -p 'python38.withPackages(ps: with ps; [ numpy toolz ])'
2. In the portion where we show how to add stuff to the user's
`XDG_CONFIG_HOME`, use overlays instead of `config.nix`. The former can do
everything the latter can do, but is also much more generic and powerful,
because it can compose with other files, compose with other envs, compose
with overlays that do things like swap whether tensorflow and pytorch are
built openblas/mkl/cuda stacks, and so on. The user is eventually going to
see the overlay, so to avoid confusion let's standardize on it.
An overlay by any other name would function just as well, but we generally use
`self: super:` for the regular overlays, and `python-self: python-super`.
Since the introduction of php.unwrapped there's no real need for the
phpXXbase attributes, so let's remove them to lessen potential
confusion and clutter. Also update the docs to make it clear how to
get hold of an unwrapped PHP if needed.
Rework withExtensions / buildEnv to handle currently enabled
extensions better and make them compatible with override. They now
accept a function with the named arguments enabled and all, where
enabled is a list of currently enabled extensions and all is the set
of all extensions. This gives us several nice properties:
- You always get the right version of the list of currently enabled
extensions
- Invocations chain
- It works well with overridden PHP packages - you always get the
correct versions of extensions
As a contrived example of what's possible, you can add ImageMagick,
then override the version and disable fpm, then disable cgi, and
lastly remove the zip extension like this:
{ pkgs ? (import <nixpkgs>) {} }:
with pkgs;
let
phpWithImagick = php74.withExtensions ({ all, enabled }: enabled ++ [ all.imagick ]);
phpWithImagickWithoutFpm743 = phpWithImagick.override {
version = "7.4.3";
sha256 = "wVF7pJV4+y3MZMc6Ptx21PxQfEp6xjmYFYTMfTtMbRQ=";
fpmSupport = false;
};
phpWithImagickWithoutFpmZip743 = phpWithImagickWithoutFpm743.withExtensions (
{ enabled, all }:
lib.filter (e: e != all.zip) enabled);
phpWithImagickWithoutFpmZipCgi743 = phpWithImagickWithoutFpmZip743.override {
cgiSupport = false;
};
in
phpWithImagickWithoutFpmZipCgi743
* ghcHEAD: bump to 8.11.20200403
* ghcHead: reduce diff vs. 8.10.1
dontAddExtraLibs was removed by accident (IMO) in ea19a8ed1e
* ghcHEAD: add ability to use system libffi
- enable nixpkgs' libffi
- minimise diffs against 8.10.1
- remove patching
* remove configure warning about --with-curses-includes
configure: WARNING: unrecognized options: --with-curses-includes
This provides a means to build a PHP package based on a list of
extensions from another.
For example, to generate a package with all default extensions
enabled, except opcache, but with ImageMagick:
php.withExtensions (e:
(lib.filter (e: e != php.extensions.opcache) php.enabledExtensions)
++ [ e.imagick ])
So now we have only packages for human interaction in php.packages and
only extensions in php.extensions. With this php.packages.exts have
been merged into the same attribute set as all the other extensions to
make it flat and nice.
The nextcloud module have been updated to reflect this change as well
as the documentation.
- Use git.Repo(ROOT, search_parent_directories=True) to find nixpkgs
repo.
- Don't commit overrides.nix.
- Remove "-a" short argument.
- Remove "--commit" flag and commit by default.
- Improve help/error messages.
- Favor closure pattern over classes.Use a closure to wrap the update
function with state rather than a callable class.
- break NixpkgsRepo class into functions
- Optional None-type arguments
- Remove repo checks from update.py. Git is too flexible and permits too
many workflows for my attempt to replace documentation with code to work.
My goal would be to separate the `--add` functionality from the update
functionality in the near term and then there will be no reason for this
usage to create commits anyway.
Previously, we would asssert that the lockfiles are consistent during the
unpackPhase, but if the pkg has a patch for the lockfile itself then we must
wait until the patchPhase is complete to check.
This also removes an implicity dependency on the src attribute coming from
`fetchzip` / `fetchFromGitHub`, which happens to name the source directory
"source". Now we glob for it, so different fetchers will work consistently.
This has several advantages:
1. It takes up less space on disk in-between builds in the nix store.
2. It uses less space in the binary cache for vendor derivation packages.
3. It uses less network traffic downloading from the binary cache.
4. It plays nicely with hashed mirrors like tarballs.nixos.org, which only
substitute --flat hashes on single files (not recursive directory hashes).
5. It's consistent with how simple `fetchurl` src derivations work.
6. It provides a stronger abstraction between input src-package and output
package, e.g., it's harder to accidentally depend on the src derivation at
runtime by referencing something like `${src}/etc/index.html`. Likewise, in
the store it's harder to get confused with something that is just there as a
build-time dependency vs. a runtime dependency, since the build-time
src dependencies are tarred up.
Disadvantages are:
1. It takes slightly longer to untar at the start of a build.
As currently implemented, this attaches the compacted vendor.tar.gz feature as a
rider on `verifyCargoDeps`, since both of them are relatively newly implemented
behavior that change the `cargoSha256`.
If this PR is accepted, I will push forward the remaining rust packages with a
series of treewide PRs to update the `cargoSha256`s.
No material changes to docs, but trying to sanitize them for consistent
readability prior to looking at #75837.
- Use `*` for lists instead of `-`. I have no opinion one way or the other, but
the latter was only used in 1-2 places.
- Pad the code blocks with whitespace.
- Wrap to 80 characters, except for a few 1-liners that were only slightly over.
When updating the section to python 3 some places still
referred to pythonPackages and were overlooked.
Decided to switch it to be more similar to the first
example binding pythonPackages and clarified comments a
bit based on confusion I observed on IRC.
Related to https://github.com/NixOS/nixpkgs/pull/77569
Updating section about imperative use of ad-hoc virtual-environments for
use of pythons built-in `venv` module via venvShellHook. Also trying to
make it a bit friendlier to beginners by adding a bit more explanation
to the code snippet and some remarks old-school virtualenv.
Adjusting for venvShellHook and adding manual example
Adding pip install and replacing python2 example with python3
When modSha256 is null, disable the nix sandbox instead of using a
fixed-output derivation. This requires the nix-daemon to have
`sandbox = relaxed` set in their config to work properly.
Because the output is (hopefully) deterministic based on the inputs,
this should give a reproducible output. This is useful for development
outside of nixpkgs where re-generating the modSha256 on each mod.sum
changes is cumbersome.
Don't use this in nixpkgs! This is why null is not the default value.
The package set is not maintained. It is also not used by most of the
BEAM community. Removing it to allow a more useful set of tools fit to
the BEAM community in Nixpkgs.
