Add automatic package pushing to binary caches

.ci/attic-auth.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+set -uo pipefail
+
+mkdir -p ~/.config/attic
+cat <<EOF > ~/.config/attic/config.toml
+default-server = "public"
+
+[servers.public]
+endpoint = "http://192.168.102.136:9200"
+token = "$ATTIC_AUTH_TOKEN"
+EOF

.github/workflows/ci.yml

@@ -15,7 +15,7 @@ concurrency:
 jobs:
   stack:
     name: Stack tests
-    runs-on: ubuntu-latest
+    runs-on: self-hosted
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -142,6 +142,82 @@ jobs:
         run: |
           .ci/test_whitespace.sh
 
+  packages:
+    name: Push package to cache
+    runs-on: self-hosted
+    strategy:
+      matrix:
+        ghc-version: [ "ghc9101", "ghc982", "ghc964" ]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build & test
+        run: |
+          # The -L flag outputs build logs to stderr
+          nix build -L .#${{ matrix.ghc-version }}.clash-protocols-base
+          nix build -L .#${{ matrix.ghc-version }}.clash-protocols
+
+        # Pushes the binaries to the local network
+        # url: http://192.168.102.136:9200/public
+        # public key: public:PGGlJMx1gGmU069blMqve8tS1ndzBuriUAwGBHGOo4g=
+      - name: Push package to cache
+        env:
+          ATTIC_AUTH_TOKEN: ${{ secrets.ATTIC_SECRET }}
+        run: |
+          .ci/attic-auth.sh
+          attic push public $(nix path-info .#${{ matrix.ghc-version }}.clash-protocols-base)
+          attic push public $(nix path-info .#${{ matrix.ghc-version }}.clash-protocols)
+
+      - name: Push package to cachix
+        if: github.ref == 'refs/heads/main'
+        env:
+          # Having the variable be named `CACHIX_AUTH_TOKEN` authenticates cachix
+          # https://docs.cachix.org/getting-started#authenticating
+          CACHIX_AUTH_TOKEN: ${{ secrets.CACHIX_SECRET }}
+        run: |
+          nix path-info .#${{ matrix.ghc-version }}.clash-protocols-base | cachix push clash-lang
+          nix path-info .#${{ matrix.ghc-version }}.clash-protocols | cachix push clash-lang
+
+  devshells:
+    name: Push Nix developer shell to cache
+    runs-on: self-hosted
+    strategy:
+      matrix:
+        ghc-version: [ "ghc9101", "ghc982", "ghc964" ]
+    steps:
+        # There's no need to configure Nix, the dockerfile handling the GHA has it done for us!
+        # If dependencies are already cached, we can simply reuse them!
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build devshell
+        run: |
+          # Since the server is x86_64-linux, we can only build the devshell
+          # for that
+          nix build -L .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full
+
+        # Pushes the binaries to the local network
+        # url: http://192.168.102.136:9200/public
+        # public key: public:PGGlJMx1gGmU069blMqve8tS1ndzBuriUAwGBHGOo4g=
+      - name: Push devshell to cache
+        env:
+          ATTIC_AUTH_TOKEN: ${{ secrets.ATTIC_SECRET }}
+        run: |
+          .ci/attic-auth.sh
+          attic push public $(nix path-info .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full)
+
+        # Pushes the binaries to Cachix
+      - name: Push devshell to cachix
+        if: github.ref == 'refs/heads/main'
+        env:
+          # Having the variable be named `CACHIX_AUTH_TOKEN` authenticates cachix
+          # https://docs.cachix.org/getting-started#authenticating
+          CACHIX_AUTH_TOKEN: ${{ secrets.CACHIX_SECRET }}
+        run: |
+          nix path-info .#devShells.x86_64-linux.${{ matrix.ghc-version }}-full | cachix push clash-lang
+
   # Mandatory check on GitHub
   all:
     name: All jobs finished
@@ -151,8 +227,10 @@ jobs:
         fourmolu,
         linting,
         stack,
+        packages,
+        devshells,
       ]
-    runs-on: ubuntu-22.04
+    runs-on: self-hosted
     steps:
       - name: Checkout
         uses: actions/checkout@v4

README.md

@@ -668,6 +668,36 @@ in
 
 And that's it!
 
+### Cache
+
+Compiling Clash can take quite some time. To remedy the situation, we maintain a Cachix cache which can be used to speed up compilation. To add the cache, first (temporarily) install cachix:
+
+`nix shell nixpkgs#cachix`
+
+And then run:
+
+`cachix use clash-lang`
+
+And that's it! The cache is now set up and you no longer need cachix installed.
+
+Alternatively you can add the cache manually to your `nix.conf` file. Simply add the following two configurations:
+```conf
+extra-substituters = https://clash-lang.cachix.org
+extra-trusted-public-keys = clash-lang.cachix.org-1:/2N1uka38B/heaOAC+Ztd/EWLmF0RLfizWgC5tamCBg=
+```
+If a project specific cache is preferred, using a `flake.nix` with the following will only make the cache active for the specific project of the flake:
+```nix
+{
+  nixConfig = {
+    extra-substituters = [ "https://clash-lang.cachix.org" ];
+    extra-trusted-public-keys = [ "clash-lang.cachix.org-1:/2N1uka38B/heaOAC+Ztd/EWLmF0RLfizWgC5tamCBg=" ];
+  };
+  description = ...;
+  inputs = ...;
+  outputs = ...;
+}
+```
+
 # TODO
 
 0.1