Add fetch* utils

server/utils/createTempPath.js

@@ -0,0 +1,9 @@
+const path = require("path");
+const tmpdir = require("os-tmpdir");
+
+function createTempPath(name, version) {
+  const hyphenName = name.replace(/\//g, "-");
+  return path.join(tmpdir(), `unpkg-${hyphenName}-${version}`);
+}
+
+module.exports = createTempPath;