groovy是一种动态脚本语言,适用于一些可变、和规则配置性的需求,目前Spring提供ScriptSource接口,支持两种类型,一种是
ResourceScriptSource,另一种是 StaticScriptSource,但是有的场景我们需要把groovy代码放进DB中,所以我们需要扩展这个。
ResourceScriptSource:在 resources 下面写groovy类
StaticScriptSource:把groovy类代码放进XML里
DatabaseScriptSource:把groovy类代码放进数据库中
工程模块为:
ResourceScriptSource
groovy的pom
<dependency>
<artifactId>groovy-all</artifactId>
<groupId>org.codehaus.groovy</groupId>
<version>2.1.9</version>
<scope>compile</scope>
</dependency>
HelloService接口
package com.maple.resource.groovy;
/**
* @author: maple
* @version: HelloService.java, v 0.1 2020年09月25日 21:26 maple Exp $
*/
public interface HelloService {
String sayHello();
}
resources下面建groovy实现类
package com.maple.resource.groovy
class HelloServiceImpl implements HelloService {
String name;
@Override
String sayHello() {
return "Hello $name. Welcome to resource in Groovy.";
}
}
在spring-groovy.xml中配置
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:lang="http://www.springframework.org/schema/lang"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/lang
http://www.springframework.org/schema/lang/spring-lang.xsd">
<lang:groovy id="helloService" script-source="classpath:groovy/HelloServiceImpl.groovy">
<lang:property name="name" value="maple"></lang:property>
</lang:groovy>
</beans>
主类 GroovyResourceApplication
package com.maple.resource;
import com.maple.resource.groovy.HelloService;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.support.ClassPathXmlApplicationContext;
@SpringBootApplication
public class GroovyResourceApplication {
public static void main(String[] args) {
//SpringApplication.run(GroovyResourceApplication.class, args);
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring-groovy.xml");
HelloService bean = context.getBean(HelloService.class);
String sayHello = bean.sayHello();
System.out.println(sayHello);
}
}
启动并测试
StaticScriptSource
groovy的pom
<dependency>
<artifactId>groovy-all</artifactId>
<groupId>org.codehaus.groovy</groupId>
<version>2.1.9</version>
<scope>compile</scope>
</dependency>
HelloService接口
package com.maple.groovy.staticscript.groovy;
/**
* @author: maple
* @version: HelloService.java, v 0.1 2020年09月25日 21:26 maple Exp $
*/
public interface HelloService {
String sayHello();
}
在spring-groovy.xml中配置具体的实现类
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:lang="http://www.springframework.org/schema/lang"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/lang
http://www.springframework.org/schema/lang/spring-lang.xsd">
<lang:groovy id="helloService">
<lang:inline-script>
import com.maple.groovy.staticscript.groovy.HelloService
class HelloServiceImpl implements HelloService {
String name;
@Override
String sayHello() {
return "Hello $name. Welcome to static script in Groovy.";
}
}
</lang:inline-script>
<lang:property name="name" value="maple"/>
</lang:groovy>
</beans>
主类 GroovyStaticscriptApplication
package com.maple.groovy.staticscript;
import com.maple.groovy.staticscript.groovy.HelloService;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.support.ClassPathXmlApplicationContext;
@SpringBootApplication
public class GroovyStaticscriptApplication {
public static void main(String[] args) {
//SpringApplication.run(GroovyStaticscriptApplication.class, args);
ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("spring-groovy.xml");
HelloService bean = context.getBean(HelloService.class);
String sayHello = bean.sayHello();
System.out.println(sayHello);
}
}
启动并测试
DatabaseScriptSource
下面我们先建表,把基本工作做完,这里我使用mybatisplus,dao、service等代码省略
CREATE TABLE `groovy_script` (
`id` BIGINT ( 20 ) NOT NULL AUTO_INCREMENT,
`script_name` VARCHAR ( 64 ) NOT NULL COMMENT 'script name',
`script_content` text NOT NULL COMMENT 'script content',
`status` VARCHAR ( 16 ) NOT NULL DEFAULT 'ENABLE' COMMENT 'ENABLE/DISENABLE',
`extend_info` VARCHAR ( 4096 ) DEFAULT NULL,
`created_time` TIMESTAMP ( 6 ) NOT NULL DEFAULT CURRENT_TIMESTAMP ( 6 ),
`modified_time` TIMESTAMP ( 6 ) NOT NULL DEFAULT CURRENT_TIMESTAMP ( 6 ) ON UPDATE CURRENT_TIMESTAMP ( 6 ),
PRIMARY KEY ( `id` )
) ENGINE = INNODB AUTO_INCREMENT = 1 DEFAULT CHARSET = utf8mb4 COMMENT = 'groovy script';
INSERT INTO `gane-platform`.`groovy_script`(`id`, `script_name`, `script_content`, `status`, `extend_info`, `created_time`, `modified_time`) VALUES (1, 'helloService', 'package com.maple.resource.groovy\r\n\r\nimport com.maple.database.groovy.HelloService\r\n\r\npublic class HelloServiceImpl implements HelloService {\r\n\r\n @Override\r\n String sayHello(String name) {\r\n return \"Hello \"+name+\". Welcome to database in Groovy.\";\r\n }\r\n}', 'ENABLE', NULL, '2020-09-26 17:16:36.477818', '2020-09-27 08:23:10.790553');
方法一:
1、实时读取DB里的groovy脚本文件
2、利用GroovyClassLoader去编译脚本文件
3、把class对象注入成Spring bean
4、反射调用脚本的方法
package com.maple.database.controller;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.maple.database.entity.GroovyScript;
import com.maple.database.groovy.SpringContextUtils;
import com.maple.database.service.GroovyScriptService;
import groovy.lang.GroovyClassLoader;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
* @author: maple
* @version: GroovyController.java, v 0.1 2020年09月26日 17:18 maple Exp $
*/
@RestController
public class GroovyController {
@Resource
private GroovyScriptService groovyScriptService;
@GetMapping("/groovyTest")
private String groovyTest() throws IllegalAccessException, InstantiationException, InvocationTargetException, NoSuchMethodException {
GroovyScript groovyScript = groovyScriptService.getOne(new QueryWrapper<GroovyScript>()
.eq("script_name", "helloService").eq("status", "ENABLE"));
System.out.println(groovyScript.getScriptContent());
Class clazz = new GroovyClassLoader().parseClass(groovyScript.getScriptContent());
Object o = clazz.newInstance();
SpringContextUtils.autowireBean(o);
Method method = clazz.getMethod("sayHello", String.class);
return (String) method.invoke(o, "maple");
}
}
package com.maple.database.groovy;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
/**
* @author: maple
* @version: SpringContextUtils.java, v 0.1 2020年09月26日 17:29 maple Exp $
*/
@Component
public class SpringContextUtils implements ApplicationContextAware {
static ApplicationContext context;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
SpringContextUtils.context = applicationContext;
}
public static void autowireBean(Object bean) {
context.getAutowireCapableBeanFactory().autowireBean(bean);
}
public static ApplicationContext getContext() {
return context;
}
public static <T> T getBean(Class<T> clazz) {
return context.getBean(clazz);
}
public static <T> T getBean(String name) {
return (T) context.getBean(name);
}
}
启动测试结果为:
总结:
优点:实时读取DB里的脚本,当脚本更改时,可以直接修改DB,对代码无侵入
缺点:每次都要查询DB,反射调用代码写死了
方法二:
1、我们模仿groovy-resource的思路,resource的XML配置是下面这样的
<lang:groovy id="helloService" script-source="classpath:groovy/HelloServiceImpl.groovy" />
所以,我们可以把DatabaseScriptSource的XML保存成这种格式
<lang:groovy id="helloService" script-source="database:helloService"/>
2、然后模仿Spring保存成XML格式的document的思路,我们也把groovy保存成XML格式的document,放进内存里
3、groovy的关键处理类是ScriptFactoryPostProcessor,当 Spring 装载应用程序上下文时,它首先创建工厂 bean(例如 GroovyScriptFactory bean)。然后,执行ScriptFactoryPostProcessor bean,用实际的脚本对象替换所有的工厂 bean。例如,我们本次测试的配置产生一个名为 helloService 的 bean,它的类型是groovierspring.GroovyHelloService。(如果启用 Spring 中的 debug 级日志记录,并观察应用程序上下文的启动,将会看到 Spring 首先创建一个名为 scriptFactory.helloService 的工厂 bean,然后 ScriptFactoryPostProcessor 从该工厂 bean 创建 helloService bean)。
我们发现ScriptFactoryPostProcessor这个类中,有getScriptSource这个方法,该方法里有convertToScriptSource方法
在convertToScriptSource这个方法中,他默认支持我们前面说过的static script和resource两种类型,但是现在我们新增了一种database类型,所以我们需要重写该方法,其他的工作都一样,交给ScriptFactoryPostProcessor帮我们去处理。
package com.maple.database.manage;
import com.maple.database.groovy.DatabaseScriptSource;
import org.apache.commons.lang3.StringUtils;
import org.springframework.core.io.ResourceLoader;
import org.springframework.scripting.ScriptSource;
import org.springframework.scripting.support.ResourceScriptSource;
import org.springframework.scripting.support.ScriptFactoryPostProcessor;
import org.springframework.scripting.support.StaticScriptSource;
import org.springframework.stereotype.Component;
/**
* @author: maple
* @version: CustomerScriptFactoryPostProcessor.java, v 0.1 2020年09月26日 20:36 maple Exp $
*/
@Component
public class CustomerScriptFactoryPostProcessor extends ScriptFactoryPostProcessor {
@Override
protected ScriptSource convertToScriptSource(String beanName, String scriptSourceLocator, ResourceLoader resourceLoader) {
if (scriptSourceLocator.startsWith(INLINE_SCRIPT_PREFIX)) {
return new StaticScriptSource(scriptSourceLocator.substring(INLINE_SCRIPT_PREFIX.length()), beanName);
}
if (scriptSourceLocator.startsWith(GroovyConstant.SCRIPT_SOURCE_PREFIX)) {
return new DatabaseScriptSource(StringUtils.substringAfter(scriptSourceLocator, GroovyConstant.SCRIPT_SOURCE_PREFIX));
}
return new ResourceScriptSource(resourceLoader.getResource(scriptSourceLocator));
}
}
但是我们也要看看ScriptFactoryPostProcessor帮我们处理的其他工作都是什么:
(1)predictBeanType:是 Spring 中从 BeanDefinition 中提取 Bean 类型的底层 API
(2)我们再来看prepareScriptBeans准备了什么
(3)scriptBeanFactory.registerBeanDefinition,向beanDefinitionMap里put键值对
(4)createScriptedObjectBeanDefinition
(5)Class<?> scriptedType = scriptFactory.getScriptedObjectType(scriptSource);
这句是为了拿到我们具体的实现类,也是我们的基础,它里面就是用GroovyClassLoader去编译我们的groovy脚本内容,并返回了Class<?> scriptClass我们的HelloServiceImpl
(6)ScriptSource scriptSource = getScriptSource(scriptFactoryBeanName, scriptFactory.getScriptSourceLocator());
这里首先去我们下面新增的DatabaseScriptSource里拿到groovy脚本内容,并放进map里,返回DatabaseScriptSource
4、新增DatabaseScriptSource类
package com.maple.database.groovy;
import com.maple.database.groovy.cache.GroovyCache;
import org.springframework.scripting.ScriptSource;
import org.springframework.util.StringUtils;
import java.io.IOException;
/**
* @author: maple
* @version: DatabaseScriptSource.java, v 0.1 2020年09月26日 15:37 maple Exp $
*/
public final class DatabaseScriptSource implements ScriptSource {
/**
* 脚本名称
*/
private String scriptName;
/**
* 构造函数
*
* @param scriptName
*/
public DatabaseScriptSource(String scriptName) {
this.scriptName = scriptName;
}
@Override
public String getScriptAsString() throws IOException {
return GroovyCache.getByName(scriptName).getGroovyContent();
}
@Override
public boolean isModified() {
return false;
}
@Override
public String suggestedClassName() {
return StringUtils.stripFilenameExtension(this.scriptName);
}
}
5、把我们的CustomerScriptFactoryPostProcessor放进Spring的List<BeanPostProcessor>中
这样的话,我们就能从Spring容器中获取helloService的bean实例了,测试:
package com.maple.database.controller;
import com.maple.database.groovy.HelloService;
import com.maple.database.groovy.SpringContextUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @author: maple
* @version: GroovyController.java, v 0.1 2020年09月26日 17:18 maple Exp $
*/
@RestController
public class NewGroovyController {
@GetMapping("/newGroovyTest")
private String newGroovyTest() {
HelloService helloService = SpringContextUtils.getBean("helloService");
String hello = helloService.sayHello("maple");
System.out.println(hello);
return hello;
}
}
总结:
优点:项目初始化的时候,就把DB里的groovy脚本读取到,放进本次缓存里,并交给Spring管理,减少与DB的交互次数;没有硬编码,扩展性更好。
缺点:当DB里的groovy脚本文件需要修改时,我们改完之后不能立即生效,需要重启工程或者刷新本次缓存,再次放进Spring容器里才行
附上核心处理类:GroovyDynamicLoader,部分代码不全的话,可以私信我
package com.maple.database.manage;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.maple.database.entity.GroovyScript;
import com.maple.database.groovy.cache.GroovyCache;
import com.maple.database.groovy.cache.GroovyInfo;
import com.maple.database.service.GroovyScriptService;
import groovy.lang.GroovyClassLoader;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.xml.ResourceEntityResolver;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.Configuration;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import javax.annotation.Resource;
import java.util.List;
import java.util.stream.Collectors;
/**
* @author: maple
* @version: GroovyDynamicLoader.java, v 0.1 2020年09月26日 20:00 maple Exp $
*/
@Configuration
public class GroovyDynamicLoader implements ApplicationContextAware, InitializingBean {
private ConfigurableApplicationContext applicationContext;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = (ConfigurableApplicationContext) applicationContext;
}
@Resource
private GroovyScriptService groovyScriptService;
private static final GroovyClassLoader groovyClassLoader = new GroovyClassLoader(GroovyDynamicLoader.class.getClassLoader());
@Override
public void afterPropertiesSet() throws Exception {
init();
}
private void init() {
List<GroovyScript> groovyScripts = groovyScriptService.list(new QueryWrapper<GroovyScript>().eq("status", "ENABLE"));
List<GroovyInfo> groovyInfos = groovyScripts.stream().map(groovyScript -> {
GroovyInfo groovyInfo = new GroovyInfo();
groovyInfo.setClassName(groovyScript.getScriptName());
groovyInfo.setGroovyContent(groovyScript.getScriptContent());
return groovyInfo;
}).collect(Collectors.toList());
if (CollectionUtils.isEmpty(groovyInfos)) {
return;
}
ConfigurationXMLWriter config = new ConfigurationXMLWriter();
addConfiguration(config, groovyInfos);
GroovyCache.put2map(groovyInfos);
loadBeanDefinitions(config);
}
private void addConfiguration(ConfigurationXMLWriter config, List<GroovyInfo> groovyInfos) {
for (GroovyInfo groovyInfo : groovyInfos) {
writeBean(config, groovyInfo);
}
}
private void writeBean(ConfigurationXMLWriter config, GroovyInfo groovyInfo) {
if (checkSyntax(groovyInfo)) {
DynamicBean bean = composeDynamicBean(groovyInfo);
config.write(GroovyConstant.SPRING_TAG, bean);
}
}
private boolean checkSyntax(GroovyInfo groovyInfo) {
try {
groovyClassLoader.parseClass(groovyInfo.getGroovyContent());
} catch (Exception e) {
return false;
}
return true;
}
private DynamicBean composeDynamicBean(GroovyInfo groovyInfo) {
DynamicBean bean = new DynamicBean();
String scriptName = groovyInfo.getClassName();
Assert.notNull(scriptName, "parser className cannot be empty!");
//设置bean的属性,这里只有id和script-source。
bean.put("id", scriptName);
bean.put("script-source", GroovyConstant.SCRIPT_SOURCE_PREFIX + scriptName);
return bean;
}
private void loadBeanDefinitions(ConfigurationXMLWriter config) {
String contextString = config.getContent();
if (StringUtils.isBlank(contextString)) {
return;
}
XmlBeanDefinitionReader beanDefinitionReader = new XmlBeanDefinitionReader((BeanDefinitionRegistry) this.applicationContext.getBeanFactory());
beanDefinitionReader.setResourceLoader(this.applicationContext);
beanDefinitionReader.setBeanClassLoader(applicationContext.getClassLoader());
beanDefinitionReader.setEntityResolver(new ResourceEntityResolver(this.applicationContext));
beanDefinitionReader.loadBeanDefinitions(new InMemoryResource(contextString));
String[] postProcessorNames = applicationContext.getBeanFactory().getBeanNamesForType(CustomerScriptFactoryPostProcessor.class, true, false);
for (String postProcessorName : postProcessorNames) {
applicationContext.getBeanFactory().addBeanPostProcessor((BeanPostProcessor) applicationContext.getBean(postProcessorName));
}
}
}