just: use released artifacts for demodir

When demoing Contrast, we usually want a stable software version with a
minimum amount of surprises, so we would like to use the released binary
and coordinator YAML for that. This commit adds a script that downloads
the artifacts, which is a bit complicated because of visibility
restrictions, and modifies the just target to use this script.

Co-authored-by: Paul Meyer <[email protected]>

justfile

@@ -187,16 +187,18 @@ fmt:
 lint:
     nix run .#scripts.golangci-lint -- run
 
-demodir cli=default_cli: undeploy coordinator initializer
+demodir namespace="default": coordinator initializer
     #!/usr/bin/env bash
     d=$(mktemp -d)
     echo "Creating demo directory at ${d}"
-    nix build .#{{ cli }}
-    cp ./result-cli/bin/contrast "${d}/contrast"
     cp -R ./deployments/emojivoto "${d}/deployment"
+    rm -f "${d}/deployment/coordinator.yml"
     nix run .#scripts.patch-contrast-image-hashes -- "${d}/deployment"
     nix run .#kypatch images -- "${d}/deployment" \
         --replace ghcr.io/edgelesssys ${container_registry}
+    nix run .#kypatch namespace -- "${d}/deployment" \
+        --replace edg-default {{ namespace }}
+    nix run .#scripts.fetch-latest-contrast -- {{ namespace }} "${d}"
     echo "Demo directory ready at ${d}"
 
 # Cleanup auxiliary files, caches etc.

packages/scripts.nix

@@ -168,4 +168,24 @@ with pkgs;
       popd >/dev/null
     '';
   };
+
+  fetch-latest-contrast = writeShellApplication {
+    name = "fetch-latest-contrast";
+    runtimeInputs = [
+      jq
+      github-cli
+    ];
+    text = ''
+      namespace=$1
+      targetDir=$2
+      release=$(gh release list --json name,isLatest | jq -r '.[] | select(.isLatest) | .name')
+      gh release download "$release" \
+        --repo edgelesssys/contrast \
+        -D "$targetDir" \
+        --skip-existing
+      chmod a+x "$targetDir/contrast"
+
+      yq -i ".metadata.namespace = \"$namespace\"" "$targetDir/coordinator.yaml"
+    '';
+  };
 }