Only allows adding to a writable playlist

ui/src/common/Writable.js

@@ -0,0 +1,22 @@
+import { cloneElement } from 'react'
+
+export const isWritable = (owner) => {
+  return (
+    localStorage.getItem('username') === owner ||
+    localStorage.getItem('role') === 'admin'
+  )
+}
+
+export const isReadOnly = (owner) => {
+  return !isWritable(owner)
+}
+
+const Writable = (props) => {
+  const { record, children } = props
+  if (isWritable(record.owner)) {
+    return cloneElement(children, props)
+  }
+  return null
+}
+
+export default Writable