JarCastingrenjin-spring-boot-starter
A spring boot starter to run Renjin R code in a spring boot app
To use it, add the following dependency to your pom.xml
<dependency>
<groupId>se.alipsa</groupId>
<artifactId>renjin-spring-boot-starter</artifactId>
<version>1.0.0</version>
</dependency>
Then, in your spring boot application, you can wire in the ScriptEngine to execute R code. E.g. (very simplified)
package my.springapp;
import org.renjin.script.RenjinScriptEngine;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import javax.script.ScriptException;
import java.io.IOException;
@Service
public class AnalysisEngine {
private final RenjinScriptEngine scriptEngine;
@Autowired
public AnalysisEngine(RenjinScriptEngine scriptEngine) {
this.scriptEngine = scriptEngine;
}
public SEXP runScript(String script) throws ScriptException {
return (SEXP)scriptEngine.eval(script);
}
}
Since any executions in the same session share data (e.g. variables in the global environment), in some cases you need to have a new Session for every script invocation. As session creation is a bit expensive, there is an Object pool of Script Engines with a unique session for each that you can use as follows:
import org.renjin.script.RenjinScriptEngine;
import org.renjin.sexp.SEXP;
import org.springframework.beans.factory.annotation.Autowired;;
import org.springframework.stereotype.Service;
import se.alipsa.renjin.starter.RenjinSessionEnginePool;
import java.util.Map;
@Service
public class ReportEngine {
private final RenjinSessionEnginePool renjinSessionEnginePool;
@Autowired
public ReportEngine(RenjinSessionEnginePool renjinSessionEnginePool) {
this.renjinSessionEnginePool = renjinSessionEnginePool;
}
private SEXP runScript(String script, Map<String, Object> params) throws Exception {
RenjinScriptEngine scriptEngine = null;
try {
scriptEngine = renjinSessionEnginePool.borrowObject();
params.forEach(scriptEngine::put);
return (SEXP) scriptEngine.eval(script);
} finally {
if (scriptEngine != null) {
renjinSessionEnginePool.returnObject(scriptEngine);
}
}
}
}
Note: When the engine is returned to the pool, all top level variables are removed with rm(list = ls(all.names = TRUE)) so that the next script will start with a clean environment.
For more comprehensive examples see https://github.com/perNyfelt/renjin-spring-boot-starter-examples
Configuration
Default value in bold
- se.alipsa.renjin.starter.excludeDefaultPackages=true / false
- se.alipsa.renjin.starter.packageLoader=AetherPackageLoader / ClasspathPackageLoader