Ten days after the first release candidate was made available, Prometheus 2.7 is now ready for general use.

During this last feedback period the Prometheus team only had minor issues to clean up, and compiled the release again with a security fix of programming language Go, which was issued last week.

In case you didn’t look into any of the candidates, the most notable addition is subqueries for Prometheus’ functional expression language PromQL. Those are meant to let users select ranges for queries by adding something along the lines of [<range>:<resolution]. The result is then made available as a range vector.

The 2.7 release comes with experimental support for disk size-based retention and a CORS origin flag to disable the protocol for cross-origin resource sharing and configure the number of acceptable origins if needed. Enhancements can also be found in service discovery (SD), examples including support for managed identity authentication as well as added tenant and subscription IDs in discovery metadata for Azure SD or support for application credentials based authentication for OpenStack SD.

Due to breaking changes v2.6 introduced, the Prometheus team had to rollback the Dockerfile to version 2.5.

Prometheus is a monitoring system and time series database originally developed by music streaming service SoundCloud in 2012. Since 2016 its development is now overseen by the Cloud Native Computing Foundation, which also houses container orchestrator Kubernetes, and the Envoy proxy amongst other projects.