Add container image

This change enables running emanote in a container.

.github/workflows/ci.yaml

@@ -63,3 +63,16 @@ jobs:
       - name: Deploy to GitHub Pages
         id: deployment
         uses: actions/deploy-pages@v4
+  container:
+    if: github.ref == 'refs/heads/master'
+    runs-on: x86_64-linux
+    steps:
+      - uses: actions/checkout@v3
+      - uses: DeterminateSystems/nix-installer-action@main
+      - uses: DeterminateSystems/magic-nix-cache-action@main
+
+      - name: Push Image
+        run: nix run ".#publish-container-release"
+        env:
+          GH_USERNAME: ${{ github.actor }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

docs/start/install/container.md

@@ -0,0 +1,13 @@
+# Using Container
+
+Emanote provides a standalone container.
+
+Start the live server by mounting your notebook (here `./docs`) to `/site`:
+```sh
+podman run -it -p 8080:8080 -v ./docs:/site:z ghcr.io/srid/emanote run -p 8080
+```
+
+Build the static pages:
+```sh
+podman run -it -v ./docs:/site:z -v ./output:/output:z ghcr.io/srid/emanote gen /output
+```

nix/modules/flake-parts/container.nix

@@ -0,0 +1,37 @@
+{ root, ... }: {
+  perSystem = { pkgs, config, ... }:
+    let
+      emanote = config.packages.emanote;
+      container-name = "ghcr.io/srid/emanote";
+      container = pkgs.dockerTools.streamLayeredImage {
+        name = container-name;
+        tag = "latest";
+        created = "now";
+        config.Entrypoint = [ "${emanote}/bin/emanote" ];
+        config.WorkingDir = "/site";
+        config.Labels = {
+          "org.opencontainers.image.source" = "https://github.com/srid/emanote";
+        };
+      };
+    in {
+      # Load the container locally with: `nix build .#container && ./result | podman load`
+      packages.container = container;
+
+      # Run this script in the CI to publish a new image
+      apps.publish-container-release =
+        pkgs.writeShellScriptBin "emanote-release" ''
+          set -e
+          export PATH=$PATH:${pkgs.gzip}/bin:${pkgs.skopeo}/bin
+          IMAGE="docker://${container-name}"
+
+          echo "Logging to registry..."
+          echo $GH_TOKEN | skopeo login --username $GH_USERNAME --password-stdin ghcr.io
+
+          echo "Building and publishing the image..."
+          ${container} | gzip --fast | skopeo copy docker-archive:/dev/stdin $IMAGE:${emanote.version}
+
+          echo "Tagging latest"
+          skopeo copy $IMAGE:${emanote.version} $IMAGE:latest
+        '';
+    };
+}