Spring boot整合Thymelea页面静态化实现方案
1_需求分析
如今很多大型网站为了提高并发量都会采用静态页面的方案,静态化页面可以明显提升访问速度,提高用户体验,还可以脱离数据库,减轻数据库访问上的压力.
今天我们就以博客博文静态化案例来了解一下使用Thymelea页面静态化技术.
当博主发布新文章时,伪装成数据库主库子库的canal(分布式数据同步中间件)收到主库发送的数据更新信息,向rabbitmq(消息中间件)中我们指定的交换机(exchange)绑定的通道(queue)发送一个包含文章唯一标识的信息,页面静态化服务监听消息类接到数据库消息和文章唯一标识,调用页面静态化接口(generateHtml(essayId))生成静态页面.
批注 2020-07-27 214852.jpg
2_实现代码
2-1.导入起步依赖,配置配置文件
canal服务
<dependencies>
<dependency>
<groupId>com.xpand</groupId>
<artifactId>starter-canal</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework.amqp</groupId>
<artifactId>spring-rabbit</artifactId>
</dependency>
</dependencies>
canal.client.instances.example.host=192.168.200.128
canal.client.instances.example.port=11111
canal.client.instances.example.batchSize=1000
spring.rabbitmq.host=192.168.200.128
staticPage服务
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-amqp</artifactId>
</dependency>
2-2.canal代码实现
监听类EssayListener实现
@CanalEventListener
public class EssayListener {
@Autowired
private RabbitTemplate rabbitTemplate;
@ListenPoint(schema = "jianshu_essay",table = "tb_essay")//设定监听的库名和表名
public void essay(CanalEntry.EntryType entryType,CanalEntry.RowData rowData){
Map<String, String> oldData = new HashMap<>();
rowData.getBeforeColumnsList().forEach(c->oldData.put(c.getName(),c.getValue()));//从canal里获取更新前的数据
Map<String, String> newData = new HashMap<>();
rowData.getAfterColumnsList().forEach(column -> newData.put(column.getName(),column.getValue()));//获取更新后的数据
if ("0".equals(oldData.get("is_issue"))&& "1".equals(newData.get("is_issue"))){
rabbitTemplate.convertAndSend(RbqConfig.ESSAY_ISSUE_EXCHANGE,"",newData.get("id"));
}//判断是否是文章发布信息更新,并向rabbitmq发送消息
if ("1".equals(oldData.get("is_issue"))&& "0".equals(newData.get("is_issue"))){
rabbitTemplate.convertAndSend(RbqConfig.ESSAY_PULL_EXCHANGE,"",newData.get("id"));
}//判断是否是文章下架信息更新,并发送消息
}
}
交换机和队列声明类
@Configuration
public class RbqConfig {
public static final String UPDATE_QUERE="update_quere";
public static final String ESSAY_ISSUE_EXCHANGE="ESSAY_ISSUE_EXCHANGE";
public static final String ESSAY_PULL_EXCHANGE="ESSAY_PULL_EXCHANGE";
public static final String SEARCH_ADD_QUEUE="search_add_queue";
public static final String SEARCH_DEL_QUEUE="search_del_queue";
@Bean
public Queue UPDATE_QUERE(){
return new Queue(UPDATE_QUERE);
}
@Bean(SEARCH_ADD_QUEUE)
public Queue SEARCH_ADD_QUEUE(){
return new Queue(SEARCH_ADD_QUEUE);
}
@Bean(SEARCH_DEL_QUEUE)
public Queue SEARCH_DEL_QUEUE(){
return new Queue(SEARCH_DEL_QUEUE);
}
@Bean(ESSAY_ISSUE_EXCHANGE)
public Exchange ESSAY_ISSUE_EXCHANGE(){
return ExchangeBuilder.fanoutExchange(ESSAY_ISSUE_EXCHANGE).durable(true).build();
}
@Bean(ESSAY_PULL_EXCHANGE)
public Exchange ESSAY_PULL_EXCHANGE(){
return ExchangeBuilder.fanoutExchange(ESSAY_PULL_EXCHANGE).durable(true).build();
}
@Bean
public Binding GESSAY_ISSUE_EXCHANGE_BINDING(@Qualifier(SEARCH_ADD_QUEUE) Queue queue,@Qualifier(ESSAY_ISSUE_EXCHANGE) Exchange exchange){
return BindingBuilder.bind(queue).to(exchange).with("").noargs();
}
@Bean
public Binding ESSAY_PULL_EXCHANGE_BINDING(@Qualifier(SEARCH_DEL_QUEUE) Queue queue,@Qualifier(ESSAY_PULL_EXCHANGE) Exchange exchange){
return BindingBuilder.bind(queue).to(exchange).with("").noargs();
}
}
2-3.staticPage服务代码实现
消息监听类PageListener
@Component
public class PageListener {
@Autowired
private PageService pageService;
@RabbitListener(queues = RbqConfig.SEARCH_ADD_QUEUE)//设置监听的消息队列
public void receiveMessage(String id){
System.out.println("获取页面静态化数据id"+id);
pageService.generateHtml(id);//调用页面静态化实现接口
}
}
页面静态接口实现类pageServiceImpl
@Service
public class PageServiceImpl implements PageService {
@Value("${pagepath}")
private String pagepath;
@Autowired
private TemplateEngine templateEngine;
@Override
public void generateHtml(String Id) {
Context context = new Context();//创建用于存储文章相关信息的相关数据
Map<String, Object> itemData = this.getItemData(Id);//获取文章数据
context.setVariables(itemData);
File file = new File(pagepath);//获取生成的静态页面存储的位置
if (!file.exists()){
file.mkdir();//判断如果不存在指定文件就新建
}
File file1 = new File(file + "/" + Id + ".html");//生成文件的名称,这里用文章唯一标识作为名称
Writer writer = null;
try {
writer = new PrintWriter(file1);//定义输出流
templateEngine.process("item",context,writer);//调用thymeleaf提供的方法生成静态页面,分别传入模板名称,页面数据,输出流
} catch (FileNotFoundException e) {
e.printStackTrace();
}finally {
try {
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
