fix readme by seata at

ipipman · ipipman · commit 61303eaa1b60 · 2020-12-11T17:27:55.000+08:00
diff --git a/springboot-seata-at-sample/README.md b/springboot-seata-at-sample/README.md
@@ -198,6 +198,75 @@ store {
 > 测试事务回滚成功场景：http://127.0.0.1:8084/api/business/purchase/rollback
 
 
+##### 5. Seata-AT模式实战：因篇幅有限，只对核心代码进行说明
+
+###### 5.1 在所有分支事务设置全局事务XID：Seata的事务上下文由RootContext来管理。应用开启全局事务后，所有的分支事务都必须绑定这个全局的XID。当事务结束（提交或回滚完成），RootContext会自动解绑XID。另外RootContext是基于ThreadLocal线程安全的。（本次测试是在SpringBoot使用的是HTTP方式，所以才需要通过HTTP过滤器手动进行绑定XID。如果是Dubbo或SpringCloud环境，则框架层自动绑定）
+
+```java
+@Component
+public class SeataFilter implements Filter {
+
+    @Override
+    public void init(FilterConfig filterConfig) throws ServletException {
+    }
+
+    @Override
+    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
+        HttpServletRequest req = (HttpServletRequest) servletRequest;
+        String xid = req.getHeader(RootContext.KEY_XID.toLowerCase());
+        boolean isBind = false;
+        if (StringUtils.isNotBlank(xid)) {
+            //绑定全局事务XID（Global Transaction）
+            RootContext.bind(xid);
+            isBind = true;
+        }
+        try {
+            filterChain.doFilter(servletRequest, servletResponse);
+        } finally {
+            if (isBind) {
+                RootContext.unbind();
+            }
+        }
+    }
+
+    @Override
+    public void destroy() {
+    }
+}
+```
+
+###### 5.2 开启AT全局事务：在Seata中AT模式和TCC模式一样，业务方需要使用@GlobalTransactional注解来开启全局事务（Global Transaction），会初始化GlobalTransactionInterceptor拦截器，开启一个全局事务，获取全局的事务ID（即RootContext.getXID()）
+
+```java
+@Service
+@RequiredArgsConstructor(onConstructor_ = {@Autowired(required = false)})
+public class BusinessService {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(BusinessService.class);
+
+    private final StorageClient storageClient;
+
+    private final OrderClient orderClient;
+
+    /**
+     * 开启分布式全局事务，完成（减库存，下订单）操作
+     *
+     * @param userId
+     * @param commodityCode
+     * @param orderCount
+     */
+    @GlobalTransactional
+    @SneakyThrows
+    public void purchase(String userId, String commodityCode, int orderCount) {
+        LOGGER.info("purchase begin ... xid: " + RootContext.getXID());
+        storageClient.deduct(commodityCode, orderCount);
+        orderClient.create(userId, commodityCode, orderCount);
+    }
+}
+
+```
+
+
 ------------
 
 
diff --git a/springboot-seata-at-sample/seata-at-business-service/src/main/java/com/ipman/sb2accountservice/service/BusinessService.java b/springboot-seata-at-sample/seata-at-business-service/src/main/java/com/ipman/sb2accountservice/service/BusinessService.java
@@ -23,7 +23,7 @@ public class BusinessService {
     private final OrderClient orderClient;
 
     /**
-     * 减库存，下订单
+     * 开启分布式全局事务，完成（减库存，下订单）操作
      *
      * @param userId
      * @param commodityCode
diff --git a/springboot-seata-tcc-sample/README.md b/springboot-seata-tcc-sample/README.md
@@ -88,9 +88,9 @@ Seata 事务模型包含了：TM（事务管理器），RM（资源管理器）
 
  <img src="https://raw.githubusercontent.com/ipipman/JavaSpringBootSamples/master/ReadmeMaterial/32361607671705_.pic_hd.jpg" width = "700" height = "400" alt="图片名称" align=center />
 
-##### Seata-TCC模式实战：核心代码
+##### Seata-TCC模式实战：因篇幅有限，只对核心代码进行说明
 
-###### 1.TCC注册分支事务：@TwoPhaseBusinessAction注解释用于标注这是一个TCC接口，会初始化TccActionInterceptor拦截器，用于注册分支事务（Branch Transaction）
+###### 1.TCC注册分支事务：@TwoPhaseBusinessAction注解用于标注这是一个TCC接口，会初始化TccActionInterceptor拦截器，用于注册分支事务（Branch Transaction）
 ```java
     /**
      * 第一个阶段：准备阶段

Original file line number	Diff line number	Diff line change
`@@ -23,7 +23,7 @@ public class BusinessService {`
`23`	`23`	`private final OrderClient orderClient;`
`24`	`24`
`25`	`25`	`/**`
`26`		`- * 减库存，下订单`
	`26`	`+ * 开启分布式全局事务，完成（减库存，下订单）操作`
`27`	`27`	`*`
`28`	`28`	`* @param userId`
`29`	`29`	`* @param commodityCode`