Hibernate Search fallback when Elastic search not available-CodePudding

Is there a fallback mechanism in Hibernate Search in order to be able to perform a search even when Elastic search cluster is not available? I know that the indexes are stored in Elastic search but can Hibernate search in this case just ignore the indexes and perform a default search? Is there a way to set this up?

CodePudding user response：

No. If Hibernate Search uses an Elasticsearch backend, it uses only that backend. If Elasticsearch is down, Hibernate Search is down.

If you want a "default search" (whatever that means), you will need to implement it in your own code, e.g.:

if ( elasticsearch available ) {
   // execute a query using Hibernate Search
}
else {
   // implement some "default" search, whatever that means
}

As to how you determine whether Elasticsearch is available, you could send a request to Elasticsearch using the underlying Rest client, or alternatively just run schema validation (which will necessarily fail if Elasticsearch is not available).

EDIT: Perhaps a better approach would be to try a normal search, catch exceptions and then fall back, e.g.:

try {

}
catch (SearchException e) {
   if ( e.getMessage().contains("connect") ) {
       // implement some "default" search, whatever that means
   }
   else {
      throw e;
   }
}