编写start脚本程序_使用可编写脚本的终结点遍历REST应用程序

编写start脚本程序

我喜欢JDK附带ScriptEngine的事实。当您要评估服务器环境中已经部署的应用程序并进行故障排除时，它非常灵活。将此REST端点添加到Java EE应用程序中，它将使您可以立即访问该应用程序的内部状态。

package myrestapp;import java.io.StringReader;
import java.util.logging.Logger;
import javax.script.Bindings;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.Context;/*** Give instant access to your internal application with dynamic scripting.* * <p>Example script:* <pre>* "sc" + servletContext + ", req=" + request;* </pre>* * <p>Example2* <pre>* names = servletContext.getAttributeNames();* while(names.hasMoreElements()) {*   name = names.nextElement();*   println(name);* }* </pre>*/
@Path("script")
public class ScriptResource {private static final Logger logger = Logger.getLogger(ScriptResource.class.getName());@Contextprivate ServletContext servletContext;@POSTpublic String script(@Context HttpServletRequest request, String scriptText) throws Exception {String engineName = "JavaScript";ScriptEngineManager manager = new ScriptEngineManager();ScriptEngine engine = manager.getEngineByName(engineName);logger.info("Running script text length=" + scriptText.length() + ", engine=" + engine);Object result = null;try (StringReader reader = new StringReader(scriptText)) {Bindings bindings = engine.createBindings();bindings.put("servletContext", servletContext);bindings.put("request", request);result = engine.eval(reader, bindings);}logger.info("Result " + result);return "" + result;}
}

注意，我已经在注释区域中给出了两个JavaScript示例。您将可以访问两个绑定变量，这两个变量应该使您可以完全访问应用程序的许多内部组件。

需要一个UI来测试此端点吗？尝试一下“ Advance Rest Client” Chrome扩展程序怎么样？（感谢我的同事Chris Griffin在这个很酷的扩展上的提示。它确实很方便！）。