Demo Clojure Server project

Just to keep up to date with current frameworks.

Dependencies

• Clojure deps tools

Featuring

• Clojure 1.10
• Dockerfile with multistage build
• Dockerfile with with native-image using graalvm

The docker image use openjdk 14 with ZGC for low latency GC set to 85% of RAM available to the container.

The native docker image uses graalvm with Java 11, and has minimal size.

Native using GraalVM

A few notes on non production or limited environments:

• Java docker image comes at 430MB and native image at 23MB
• Initial memory usage of java is at 150MB while native is at 3MB
• After load memory usage was similar, with native usig about 10% more memory
• Under load, the java version handler more requests
• The benchmark was very limited
• Tracing is not working on native

Utils

• environ for config
• clojure.logging using log4j
• prometheus metrics
• opentracing with jaeger, zipking or log

HTTP

• Ring
• jetty (http)
• reitit for routing
• cheshire for json

Environment configurations:

TODO

Tasks

clj repl start a generic REPL

clj -A:jar to create a jar

clj -A:uberjar uberjar standalone

clj run start the server with autoreload

docker build -f Dockerfile -t diogok/klj-api . to build docker image

docker build -f Dockerfile.native -t diogok/klj-api:native . to build graalvm native docker image

License

MIT