[SOLR-14763] SolrJ Client Async HTTP/2 Requests

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.7
• Fix Version/s: main (10.0), 9.6
• Component/s: SolrJ
• Assignee: James Dyer
• Reporter: Rishi Sankar
• Created: 19/Aug/20 21:03
• Updated: 28/Apr/24 19:22
• Resolved: 18/Apr/24 12:54

Description

In SOLR-14354, caomanhdat created an API to use Jetty async API to make more thread efficient HttpShardHandler requests. This added public async request APIs to Http2SolrClient and LBHttp2SolrClient. There are a few ways this API can be improved, that I will track in this issue:

1) Using a CompletableFuture-based async API signature, instead of using internal custom interfaces (Cancellable, AsyncListener) - based on this discussion.

—
The below was removed from the scope of what was delivered in 9.6; a linked JIRA will address it.

2) An async API is also useful in other HTTP/2 Solr clients as well, particularly CloudHttp2SolrClient (SOLR-14675). I will add a requestAsync method to the SolrClient class, with a default method that initially throws an unsupported operation exception (maybe this can be later updated to use an executor to handle the async request as a default impl). For now, I'll override the default implementation in the Http2SolrClient and CloudHttp2SolrClient.

Issue Links

• is related to: SOLR-17234 LBHttp2SolrClient does not skip "zombie" endpoints
• is related to: SOLR-14354 HttpShardHandler send requests in async
• is required by: SOLR-14675 CloudSolrClient requestAsync API
• relates to: SOLR-17211 HttpJdkSolrClient: Support Async
• links to: GitHub Pull Request #1770
• links to: GitHub Pull Request #2402
• links to: GitHub Pull Request #2407