Indy 1.9.6

This release is intended to address some subtle yet irritating bugs related to cache expiration from Koji content and associated metadata aggregation. It also aims to improve visibility into the content upload process so we can continue diagnosing the elevated latencies we've seen over the past couple months. Two other releases have carried these fixes, but have failed in production due to unforseen regressions or miscommunication in the team. Our new release process is designed to improve the latter problem, and our new load testing configuration has helped the former.

Changelog (1.9.5 to 1.9.6):

• Fix cascade of cache and metadata expirations flowing from expiration of the metadata cache generated from Koji and the aggregated metadata cache
• Implement better SLI measurement of content uploads, complete with subtraction of content transfer time from latency calculation
• Implement low-level content-read and content-write APM measurements
• Implement cumulative timing recording to the logging MDC, which is reported in the END message to the org.commonjava.rest.inbound logger
• Add MD5 / SHA1 headers to HEAD response for content
• Disable deflate content-encoding support since it causes problems with certain http clients
• Add support for validating remote repositories when they are added or updated (disabled by default)
• Deprecate listContents call in IndyContentClientModule in favor of browse module api
• Add timestamps for content accesses to tracked content entries (part of folo content tracking)
• Reuse existing remote repositories when modifying group membership from implied repositories POM event listener
• Add preliminary support for reporting metrics to Prometheus (currently all-or-nothing)
• Allow disabling content index (for simple, reverse-proxy Indy instances)
• Fix HTTP 400 response when uploading snapshot-versioned maven-metadata.xml files
• Skip writing http-metadata.json files for upstream 404 responses and for file types like .md5 and .sha1 (these JSON files preserve upstream response headers to make downstream response to the user more consistent)

Dependency Upgrades (1.9.5 to 1.9.6):

• Infinispan (9.4.15.Final)
• Keycloak (7.0.1)
• Swagger-ui (3.23.11)
• Jackson (2.10.1)