From 0460bee94c68dcdbe366e81ff6056573f6a6daf2 Mon Sep 17 00:00:00 2001
From: Tom Prince <tom.prince@private.storage>
Date: Tue, 14 Sep 2021 15:28:20 -0600
Subject: [PATCH] Add a helper python function wrapping nix-prefetch-url.
---
shell.nix | 17 +++++++++++++++-
tools/pylib/README.rst | 2 ++
tools/pylib/ps_tools/__init__.py | 35 ++++++++++++++++++++++++++++++++
3 files changed, 53 insertions(+), 1 deletion(-)
create mode 100644 tools/pylib/README.rst
create mode 100644 tools/pylib/ps_tools/__init__.py
diff --git a/shell.nix b/shell.nix
index ce1add06..97814a9c 100644
--- a/shell.nix
+++ b/shell.nix
@@ -1,12 +1,27 @@
let
release2105 = import ./nixpkgs-2105.nix { };
in
-{ pkgs ? release2105 }:
+{ pkgs ? release2105, lib ? pkgs.lib, python ? pkgs.python3 }:
+let
+ # This is a python envionment that has the dependencies
+ # for the development python scripts we use, and the
+ # helper library.
+ python-env = python.buildEnv.override {
+ extraLibs = [ python.pkgs.httpx ];
+ # Add `.pth` file pointing at the directory containg our helper library.
+ # This will get added to `sys.path` by `site.py`.
+ # See https://docs.python.org/3/library/site.html
+ postBuild = ''
+ echo ${lib.escapeShellArg ./tools/pylib} > $out/${lib.escapeShellArg python.sitePackages}/tools.pth
+ '';
+ };
+in
pkgs.mkShell {
shellHook = ''
export NIX_PATH="nixpkgs=${pkgs.path}";
'';
buildInputs = [
+ python-env
pkgs.morph
pkgs.jp
];
diff --git a/tools/pylib/README.rst b/tools/pylib/README.rst
new file mode 100644
index 00000000..083f6620
--- /dev/null
+++ b/tools/pylib/README.rst
@@ -0,0 +1,2 @@
+This directory contains a python package of helper functions used by the scripts in ``tools/``.
+To get this on the python path, run ``nix-shell`` in the root of the repository.
diff --git a/tools/pylib/ps_tools/__init__.py b/tools/pylib/ps_tools/__init__.py
new file mode 100644
index 00000000..278ef0f1
--- /dev/null
+++ b/tools/pylib/ps_tools/__init__.py
@@ -0,0 +1,35 @@
+"""
+Helpers for development and CI scripts.
+"""
+from __future__ import annotations
+
+import subprocess
+
+
+def get_url_hash(hash_type, name, url) -> dict[str, str]:
+ """
+ Get the nix hash of the given URL.
+
+ :returns: Dictionary of arguments suitable to pass to :nix:`pkgs.fetchzip`
+ or a function derived from it (such as :nix:`pkgs.fetchFromGitLab`)
+ to specify the hash.
+ """
+ output = subprocess.run(
+ [
+ "nix-prefetch-url",
+ "--type",
+ hash_type,
+ "--unpack",
+ "--name",
+ name,
+ url,
+ ],
+ capture_output=True,
+ check=True,
+ encoding="utf-8",
+ )
+
+ return {
+ "outputHashAlgo": hash_type,
+ "outputHash": output.stdout.strip(),
+ }
--
GitLab