[SOLR-12297] Add Http2SolrClient, capable of HTTP/1.1, HTTP/2, and asynchronous requests.

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 8.0
• Assignee: Mark Miller
• Reporter: Mark Miller
• Created: 01/May/18 03:54
• Updated: 2 days ago 16:48
• Resolved: 15/Nov/21 14:12

Description

Blocking or async support as well as HTTP2 compatible with multiplexing.

Once it supports enough and is stable, replace internal usage, allowing async, and eventually move to HTTP2 connector and allow multiplexing. Could support HTTP1.1 and HTTP2 on different ports depending on state of the world then.

The goal of the client itself is to work against HTTP1.1 or HTTP2 with minimal or no code path differences and the same for async requests (should initially work for both 1.1 and 2 and share majority of code).

The client should also be able to replace HttpSolrClient and plug into the other clients the same way.

I doubt it would make sense to keep ConcurrentUpdateSolrClient eventually though.

I evaluated some clients and while there are a few options, I went with Jetty's HttpClient. It's more mature than Apache HttpClient's support (in 5 beta) and we would have to update to a new API for Apache HttpClient anyway.

Meanwhile, the Jetty guys have been very supportive of helping Solr with any issues and I like having the client and server from the same project.

Issue Links

• blocks: SOLR-12404 Start using HTTP/2 instead of HTTP/1.1.
• Is contained by: SOLR-12430 The Star Burst Upgrade
• is part of: SOLR-12639 Umbrella JIRA for adding support HTTP/2, jira/http2
• is related to: SOLR-12406 Stop using response.sendError because it closes connections instead of allowing the client to manage connection the lifecycle.
• is related to: SOLR-12405 Add a quality of service type filter for request load management and request throttling.
• relates to: SOLR-13501 Use Http2SolrClient in DUP and remove ConcurrentUpdateHttp2SolrClient.
• relates to: SOLR-12439 Switch from Apache HttpClient to Jetty HttpClient which offers a single API for Async, Http/1.1 Http/2.
• relates to: SOLR-17201 Make Http2SolrClients not experimental