README.md

clojure-graalvm-agent-helper

Ease native configuration generation for GraalVM NativeImage. You don't have to write configurations for native image by hand, since there is Agent which might trace all the calls you make.

This tool helps you automate the process. You can leave in-context calls and production version of the jar will not contain any code which in-context wraps.

Extracted from holy-lambda micro-framework.

How to use it?

1. Add following dependency:

    io.github.FieryCod/clojure-graalvm-agent-helper {:mvn/version "0.0.1"}

   2. Use agent/in-context in your code:

    (ns example.core
      (:gen-class)
      (:require
        [fierycod.graalvm-agent-helper.core :as agent]))
   
    (agent/in-context
      (println "I can run arbitrary code in agent context. Agent will catch all the calls in context and generate native configuration out of it :)"))
   
    (agent/in-context
      (println "In case of error agent will catch it :)")
      (throw (ex-info "Ups.." {})))
   
    (defn -main
      []
      (agent/in-context (println "Since main is called I will print as well :)")))

   3. Compile with USE_AGENT_CONTEXT environment set to true, so that in-context will not be removed

   USE_AGENT_CONTEXT=true clojure -X:uberjar :aot true :jvm-opts '["-Dclojure.compiler.direct-linking=true", "-Dclojure.spec.skip-macros=true"]' :jar agent-output.jar :main-class example.core
   

   4. Run in native agent context

   java -agentlib:native-image-agent=config-output-dir=resources/native-configuration \
        -Dexecutor=native-agent \
        -jar agent-output.jar
   

   5. Compile a project without USE_IN_AGENT_CONTEXT

   clojure -X:uberjar :aot true :jvm-opts '["-Dclojure.compiler.direct-linking=true", "-Dclojure.spec.skip-macros=true"]' :jar output.jar :main-class example.core
   

   5. Feed native-image with configuration and compile

   native-image -jar output.jar \
     -H:ConfigurationFileDirectories=resources/native-configuration \
     -H:+AllowIncompleteClasspath \
     --report-unsupported-elements-at-runtime \
     --no-fallback \
     --verbose \
     --enable-url-protocols=http,https \
     --no-server \
     --initialize-at-build-time 
   

   Check example folder if you still have trouble setting it up.