apijson function支持脚本引擎，比如JavaScript、lua等

#495

Author: cloudAndMonkey

APIJSONORM/src/main/java/apijson/orm/script/JSR223ScriptExecutor.java

@@ -0,0 +1,86 @@
+package apijson.orm.script;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import javax.script.Bindings;
+import javax.script.Compilable;
+import javax.script.CompiledScript;
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+import javax.script.SimpleBindings;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.alibaba.fastjson.JSONObject;
+
+import apijson.orm.AbstractFunctionParser;
+
+/**
+ * JSR223 script engine的统一实现抽象类
+ */
+public abstract class JSR223ScriptExecutor implements ScriptExecutor {
+
+	protected final Logger log = LoggerFactory.getLogger(this.getClass());
+
+	protected ScriptEngine scriptEngine;
+
+	private final Map<String, CompiledScript> compiledScriptMap = new ConcurrentHashMap<>();
+	
+	@Override
+	public ScriptExecutor init() {
+		ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
+		scriptEngine = scriptEngineManager.getEngineByName(scriptEngineName());
+		return this;
+	}
+
+	protected abstract String scriptEngineName();
+	
+	protected abstract Object extendParameter(AbstractFunctionParser parser, JSONObject currentObject, String methodName, Object[] args);
+
+	protected abstract boolean isLockScript(String methodName);
+
+	protected String convertScript(String script) {
+		return script;
+	}
+
+	@Override
+	public void load(String name, String script) {
+		try {
+			CompiledScript compiledScript = ((Compilable) scriptEngine).compile(convertScript(script));
+			compiledScriptMap.put(name, compiledScript);
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+
+	}
+
+	@Override
+	public Object execute(AbstractFunctionParser parser, JSONObject currentObject, String methodName, Object[] args) throws Exception {
+		CompiledScript compiledScript = compiledScriptMap.get(methodName);
+		Bindings bindings = new SimpleBindings();
+		// 往脚本上下文里放入元数据
+		// 把 RequestMethod method, String tag, int version, @NotNull JSONObject request,
+		// HttpSession session 等参数作为全局参数传进去供脚本使用
+		
+		// 加载扩展属性
+		Object extendParameter = this.extendParameter(parser, currentObject, methodName, args);
+		if(extendParameter != null) {
+			bindings.put("extParam", extendParameter);
+		}
+		
+		Map<String, Object> metaMap = new HashMap<>();
+		metaMap.put("version", parser.getVersion());
+		metaMap.put("tag", parser.getTag());
+		metaMap.put("args", args);
+		bindings.put("_meta", metaMap);
+		return compiledScript.eval(bindings);
+	}
+
+	@Override
+	public void cleanCache() {
+		compiledScriptMap.clear();
+	}
+}

APIJSONORM/src/main/java/apijson/orm/script/ScriptExecutor.java

@@ -0,0 +1,17 @@
+package apijson.orm.script;
+
+import com.alibaba.fastjson.JSONObject;
+
+import apijson.orm.AbstractFunctionParser;
+
+public interface ScriptExecutor {
+
+    ScriptExecutor init();
+
+    void load(String name, String script);
+
+    Object execute(AbstractFunctionParser parser, JSONObject currentObject, String methodName, Object[] args) throws Exception;
+
+    void cleanCache();
+    
+}