add logging

node_environment/shell.nix

@@ -5,13 +5,35 @@ pkgs.mkShell {
     nodejs
   ];
   shellHook = ''
-    mkdir -p .npm
+    function log_header {
+      echo -ne "==> \e[32m\e[1m$1\e[0m\n\n"
+    }
+    function log_subheader {
+      echo -ne "--> \e[33m\e[1m$1\e[0m\n\n"
+    }
+    function log {
+      echo -ne "    $1\n"
+    }
+    
+    echo ""
+    log_header "node_environment"
+    mkdir -p .npm/bin
+    export PATH=$PWD/.npm/bin:$PATH
+    log_subheader "upgrading npm"
+    npm install -g npm --prefix $PWD/.npm
+    echo ""
     if [ -s global_packages.txt ]; then
+      log_subheader "found global_packages.txt, installing packages"
       cat global_packages.txt | xargs npm install -g --prefix $PWD/.npm
+      echo ""
     fi
     if [ -s package.json ]; then
+      log_subheader "found package.json, running 'npm install'"
       npm install
+      echo ""
     fi
-    export PATH=$PWD/.npm/bin:$PATH
+    log_header "package versions"
+    log "node $(node --version)"
+    log "npm $(npm --version)"
   '';
 }