Add basic nix development shell (#9162)

* Add basic nix development shell

* Use google-chrome instead of chromium

* Move nix stuff to subdirectory

* Update gemset, improve readme, fix shell

* Update nix README, remove .envrc

.gitignore

@@ -114,3 +114,6 @@ structure.sql
 
 # Local development docker 
 /.env
+
+# Local development direnv file
+/.envrc

nix/README.md

@@ -0,0 +1,24 @@
+# Nix development
+
+This directory contains files that ease development on nix-enabled systems. Just run `nix-shell ./nix` in the root project directory.
+
+The setup was tested on docker-enabled systems, however nothing should stop you from using this without docker.
+
+This is still a work in progress, feel free to improve as needed.
+
+## Updating gemset.nix
+
+Run `bundix --gemset=./nix/gemset.nix` to update the gemset file from the Gemlock file.
+
+## Autoloading
+
+If you have `lorri` and `direnv` installed, you can autoload the shell by adding a `.envrc` to the root directory with
+the following contents: 
+
+```
+eval "$(lorri direnv --shell-file ./nix/shell.nix)"
+```
+
+## Questions?
+
+Contact @b12f

nix/shell.nix

@@ -0,0 +1,33 @@
+{ pkgs ? import <nixpkgs> {} }:
+with pkgs;
+let 
+  op-get-test-failures = writeShellScriptBin "op-get-test-failures" ''
+    exec ${curl}/bin/curl "$$1" | grep 'rspec \.\/' | cut -f3 -d' ' | paste -s -d ' '
+  '';
+
+  gems = bundlerEnv {
+    name = "openproject-dev";
+    inherit ruby;
+    gemdir = ./.;
+  };
+in
+  mkShell {
+    nativeBuildInputs = [
+      buildPackages.ruby_2_7
+      postgresql
+      nodejs
+      tightvnc
+      bundix
+      docker-compose
+      google-chrome
+
+      gems
+
+      op-get-test-failures
+    ];
+
+    CHROME_BINARY = "${google-chrome}/bin/google-chrome";
+    OPENPROJECT_TESTING_NO_HEADLESS = "1";
+    OPENPROJECT_TESTING_AUTO_DEVTOOLS = "1";
+}
+