yarnConfigHook: init

pkgs/build-support/node/fetch-yarn-deps/default.nix

@@ -7,6 +7,9 @@
   fetchurl,
   nodejs-slim,
   prefetch-yarn-deps,
+  fixup-yarn-lock,
+  yarn,
+  makeSetupHook,
   cacert,
   callPackage,
   nix,
@@ -154,4 +157,15 @@ in
         );
     in
     lib.setFunctionArgs f (lib.functionArgs f) // { inherit tests; };
+
+  yarnConfigHook = makeSetupHook {
+    name = "yarn-config-hook";
+    propagatedBuildInputs = [
+      yarn
+      fixup-yarn-lock
+    ];
+    meta = {
+      description = "Install nodejs dependencies from an offline yarn cache produced by fetchYarnDeps";
+    };
+  } ./yarn-config-hook.sh;
 }

pkgs/build-support/node/fetch-yarn-deps/yarn-config-hook.sh

@@ -0,0 +1,37 @@
+yarnConfigHook(){
+    runHook preConfigure
+    echo "Executing yarnConfigHook"
+
+    # Use a constant HOME directory
+    mkdir -p /tmp/home
+    export HOME=/tmp/home
+    if [[ -n "$yarnOfflineCache" ]]; then
+        offlineCache="$yarnOfflineCache"
+    fi
+    if [[ -z "$offlineCache" ]]; then
+        echo yarnConfigHook: No yarnOfflineCache or offlineCache were defined\! >&2
+        exit 2
+    fi
+    yarn config --offline set yarn-offline-mirror "$offlineCache"
+    fixup-yarn-lock yarn.lock
+    yarn install \
+        --frozen-lockfile \
+        --force \
+        --production=false \
+        --ignore-engines \
+        --ignore-platform \
+        --ignore-scripts \
+        --no-progress \
+        --non-interactive \
+        --offline
+
+    # TODO: Check if this is really needed
+    patchShebangs node_modules
+
+    echo "finished yarnConfigHook"
+    runHook postConfigure
+}
+
+if [[ -z "${dontYarnInstallDeps-}" && -z "${configurePhase-}" ]]; then
+    configurePhase=yarnConfigHook
+fi

pkgs/top-level/all-packages.nix

@@ -986,6 +986,7 @@ with pkgs;
   inherit (callPackages ../build-support/node/fetch-yarn-deps { })
     fixup-yarn-lock
     prefetch-yarn-deps
+    yarnConfigHook
     fetchYarnDeps;
 
   find-cursor = callPackage ../tools/X11/find-cursor { };