make the website better :)

Signed-off-by: Xe Iaso <me@christine.website>

blog/nix-flakes-4-wsl-2022-04-23.markdown

@@ -0,0 +1,310 @@
+---
+title: "Nix Flakes on WSL"
+date: 2022-05-04
+series: nix-flakes
+tags:
+ - nixos
+ - wsl
+vod:
+  youtube: https://youtu.be/VzQ_NwFJObc
+  twitch: https://www.twitch.tv/videos/1464781566
+---
+
+About five years ago, Microsoft released the Windows Subsystem for Linux
+([WSL](https://docs.microsoft.com/en-us/windows/wsl/)). This allows you to run
+Linux programs on a Windows machine. When they released WSL version 2 in 2019,
+this added support for things like Docker and systemd. As a result, this is
+enough to run NixOS on Windows.
+
+<xeblog-conv name="Mara" mood="hacker">This will give you an environment to run
+Nix and Nix Flakes commands with. You can use this to follow along with this
+series without having to install NixOS on a VM or cloud server.
+</xeblog-conv>
+
+## Installation
+
+Head to the NixOS-WSL [releases
+page](https://github.com/nix-community/NixOS-WSL/releases/) and download the
+`nixos-wsl-installer-fixed.tar.gz` file to your Downloads folder.
+
+Then open Powershell and make a folder called `WSL`:
+
+```powershell
+New-Item -Path .\WSL -ItemType Directory
+```
+
+<xeblog-conv name="Mara" mood="hacker">It's worth noting that Powershell does
+have a bunch of aliases for common coreutils commands to the appropriate
+Powershell CMDlets. However these aliases are <b>NOT</b> flag-compatible and use
+the Powershell semantics instead of the semantics of the command it is aliasing.
+This will bite you when you use commands like <code>wget</code> out of instinct
+to download things. In order to avoid your muscle memory betraying you, the
+Powershell CMDlets are shown here in their full overly verbose glory.
+</xeblog-conv>
+
+Then enter the directory with `Set-Location`:
+
+```powershell
+Set-Location -Path .\WSL
+```
+
+<xeblog-conv name="Mara" mood="hacker">This directory is where the NixOS root
+filesystem will live. If you want to put this somewhere else, feel free to.
+Somewhere in `%APPDATA%` will work, just as long as it's on an NTFS volume
+somewhere.
+</xeblog-conv>
+
+Make a folder for the NixOS filesystem:
+
+```powershell
+New-Item -Path .\NixOS -ItemType Directory
+```
+
+Then install the NixOS root image with the `wsl` command:
+
+```powershell
+wsl --import NixOS .\NixOS\ ..\Downloads\nixos-wsl-installer-fixed.tar.gz --version 2
+```
+
+And start NixOS once to have it install itself:
+
+```powershell
+wsl -d NixOS
+```
+
+Once that finishes, press control-D (or use the `exit` command) to exit out of
+NixOS and restart the WSL virtual machine:
+
+```powershell
+exit
+wsl --shutdown
+wsl -d NixOS
+```
+
+And then you have yourself a working NixOS environment! It's very barebones, but
+we can use it to test the `nix run` command against our gohello command:
+
+```console
+$ nix run github:Xe/gohello
+Hello reader!
+```
+
+## Local Services
+
+We can also use this NixOS environment to run a local nginx server. Open
+`/etc/nixos/configuration.nix`:
+
+```nix
+{ lib, pkgs, config, modulesPath, ... }:
+
+with lib;
+let
+  nixos-wsl = import ./nixos-wsl;
+in
+{
+  imports = [
+    "${modulesPath}/profiles/minimal.nix"
+
+    nixos-wsl.nixosModules.wsl
+  ];
+
+  wsl = {
+    enable = true;
+    automountPath = "/mnt";
+    defaultUser = "nixos";
+    startMenuLaunchers = true;
+
+    # Enable integration with Docker Desktop (needs to be installed)
+    # docker.enable = true;
+  };
+
+  # Enable nix flakes
+  nix.package = pkgs.nixFlakes;
+  nix.extraOptions = ''
+    experimental-features = nix-command flakes
+  '';
+}
+```
+
+Right after the `wsl` block, add this nginx configuration to the file:
+
+```nix
+services.nginx.enable = true;
+services.nginx.virtualHosts."test.local.cetacean.club" = {
+  root = "/srv/http/test.local.cetacean.club";
+};
+```
+
+This will create an nginx configuration that points the domain
+`test.local.cetacean.club` to the contents of the folder `/srv/http/test.local.cetacean.club`.
+
+<xeblog-conv name="Mara" mood="hacker">The <code>/srv</code> folder is set aside
+for site-specific data, which is code for "do whatever you want with this
+folder". In many cases people make a separate <code>/srv/http</code> folder and
+put each static subdomain in its own folder under that, however I am also told
+that it is idiomatic to put stuff in <code>/var/www</code>. Pick your poison.
+</xeblog-conv>
+
+Then you can test the web server with the `curl` command:
+
+```console
+$ curl http://test.local.cetacean.club
+<html>
+<head><title>404 Not Found</title></head>
+<body>
+<center><h1>404 Not Found</h1></center>
+<hr><center>nginx</center>
+</body>
+</html>
+```
+
+This is good! Nginx is running and since we haven't created the folder with our
+website content yet, this 404 means that it can't find it! Let's create the
+folder so that nginx has permission to it and we can modify things in it:
+
+```
+sudo mkdir -p /srv/http/test.local.cetacean.club
+sudo chown nixos:nginx /srv/http/test.local.cetacean.club
+```
+
+Finally we can make an amazing website. Open
+`/srv/http/test.local.cetacean.club/index.html` in nano:
+
+```
+nano /srv/http/test.local.cetacean.club/index.html
+```
+
+And paste in this HTML:
+
+```html
+<title>amazing website xD</title>
+<h1>look at my COOL WEBsite :3/h1>
+idk It's pretty random tbh, like me!! <3 :D
+```
+
+And then you can see it show up with `curl`:
+
+```console
+$ curl http://test.local.cetacean.club
+<title>amazing website xD</title>
+<h1>look at my COOL WEBsite :3/h1>
+idk It's pretty random tbh, like me!! <3 :D
+```
+
+You can also check this out in a browser by clicking
+[here](http://test.local.cetacean.club):
+
+![a browser window titled "amazing website xD" with the header "look at my
+COOL WEBsite" and content of "idk It's pretty random tbh, like me!! <3 :D"](https://cdn.christine.website/file/christine-static/blog/Screenshot+2022-04-23+141937.png)
+
+## Installing `gohello`
+
+To install the `gohello` service, first we will need to convert this machine to
+use NixOS flakes. We can do that really quick and easy by adding this file to
+`/etc/nixos/flake.nix`:
+
+<xeblog-conv name="Mara" mood="happy">Do this as root!</xeblog-conv>
+
+```nix
+{
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+  };
+  
+  outputs = { self, nixpkgs, ... }: {
+    nixosConfigurations.nixos = nixpkgs.lib.nixosSystem {
+      system = "x86_64-linux";
+      modules = [
+        ./configuration.nix
+        
+        # add things here
+      ];
+    }; 
+  };
+}
+```
+
+Then run `nix flake check` to make sure everything is okay:
+
+```
+sudo nix flake check /etc/nixos
+```
+
+And finally activate the new configuration with flakes:
+
+```
+sudo nixos-rebuild switch
+```
+
+After it thinks for a bit, you should notice that nothing happened. This is
+good, we have just converted the system over to using Nix flakes instead of the
+classic `nix-channel` rebuild method.
+
+To get `gohello` in the system, first we need to add `git` to the commands
+available on the system in `configuration.nix`:
+
+```nix
+environment.systemPackages = with pkgs; [ git ];
+```
+
+Then we can add `gohello` to our system flake:
+
+```nix
+{
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixos-unstable";
+    # XXX(Xe): this URL may change for you, such as github:Xe/gohello-http
+    gohello.url = "git+https://tulpa.dev/cadey/gohello-http?ref=main";
+  };
+
+  outputs = { self, nixpkgs, gohello, ... }: {
+    nixosConfigurations.nixos = nixpkgs.lib.nixosSystem {
+      system = "x86_64-linux";
+      modules = [
+        ./configuration.nix
+        
+        # add things here
+        gohello.nixosModule
+        ({ pkgs, ... }: {
+          xeserv.services.gohello.enable = true;
+        })
+      ];
+    }; 
+  };
+}
+```
+
+And rebuild the system with `gohello` enabled:
+
+```
+sudo nixos-rebuild switch
+```
+
+Finally, poke it with `curl`:
+
+```console
+$ curl http://gohello.local.cetacean.club
+hello world :)
+```
+
+To update it, update the flake inputs in `/etc/nixos` and run `nixos-rebuild`:
+
+```
+sudo nix flake update /etc/nixos
+sudo nixos-rebuild switch
+```
+
+---
+
+And from here you can do whatever you want with NixOS. You can use
+[containers](https://nixos.org/manual/nixos/stable/#ch-containers), set up
+arbitrary services, or plan for world domination as normal.
+
+<xeblog-conv name="Numa" mood="delet">I thought it was "to save the world from
+devastation", not "to plan for world domination". Who needs a monopoly on
+violence for world domination when you have Nix expressions?</xeblog-conv>
+
+<xeblog-conv name="Cadey" mood="coffee">Siiiiiiiiiiiiiiiiiigh.</xeblog-conv>
+
+I will use this setup in future posts to make this more accessible and easy to
+hack at without having to have a dedicated NixOS machine laying around.