message: Support basic relationship searching
diff: @@ -237,6 +237,17 @@ class Searcher {
  if (value.exact != null) {
  let innerQuery = value.exact;
  let esName = await this.client.logicalFieldToES(branch, field.sortFieldName);
  +
  + if(field.isRelationship) {
  + if (typeof innerQuery === 'string') {
  + // TODO: this completely ignores the possibility of polymorphism
  + return { term: { [`${esName}.data.id`] : innerQuery } };
  + }
  + if (Array.isArray(innerQuery)) {
  + throw new Error("Array query not supported for filtering by relationship");
  + }
  + }
  +
  if (typeof innerQuery === 'string') {
  // This is the sortFieldName because that one is designed for
  // exact matching (in addition to sorting).
  