Using lowercase for HTTP headers to make it compatible with HTTP/2 and Rack v3

prometheus / client_ruby

Prometheus instrumentation library for Ruby applications

Apache License 2.0

513 stars 149 forks source link

Using lowercase for HTTP headers to make it compatible with HTTP/2 and Rack v3 #271

Closed bitmaybewise closed 1 year ago

bitmaybewise commented 1 year ago

Given Rack is validating HTTP headers has no uppercased letters, as mentioned in this previous PR https://github.com/prometheus/client_ruby/pull/268, the exporter needs to use lowercased letters to keep compatibility.