diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/arthas-boot.md b/tutorials/katacoda/case-jad-mc-redefine-cn/arthas-boot.md new file mode 100644 index 000000000..5c6cb8a17 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/arthas-boot.md @@ -0,0 +1,16 @@ + + + + +在新的`Terminal 2`里,下载`arthas-boot.jar`,再用`java -jar`命令启动: + +`wget https://arthas.aliyun.com/doc/arthas-boot.jar +java -jar arthas-boot.jar`{{execute T2}} + +`arthas-boot`是`Arthas`的启动程序,它启动后,会列出所有的Java进程,用户可以选择需要诊断的目标进程。 + +选择第一个进程,输入 `1`{{execute T2}} ,再`Enter/回车`: + +Attach成功之后,会打印Arthas LOGO。输入 `help`{{execute T2}} 可以获取到更多的帮助信息。 + +![Arthas Boot](/arthas/scenarios/common-resources/assets/arthas-boot.png) diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/case-jad-mc-redefine.md b/tutorials/katacoda/case-jad-mc-redefine-cn/case-jad-mc-redefine.md new file mode 100644 index 000000000..72ab774fc --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/case-jad-mc-redefine.md @@ -0,0 +1,85 @@ +下面介绍通过`jad`/`mc`/`redefine` 命令实现动态更新代码的功能。 + +目前,访问 http://localhost/user/0 ,会返回500异常: + +`curl http://localhost/user/0`{{execute T3}} + +``` +{"timestamp":1550223186170,"status":500,"error":"Internal Server Error","exception":"java.lang.IllegalArgumentException","message":"id < 1","path":"/user/0"} +``` + +下面通过热更新代码,修改这个逻辑。 + +### jad反编译UserController + +`jad --source-only com.example.demo.arthas.user.UserController > /tmp/UserController.java`{{execute T2}} + +jad反编译的结果保存在 `/tmp/UserController.java`文件里了。 + +再打开一个`Terminal 3`,然后用vim来编辑`/tmp/UserController.java`: + +`vim /tmp/UserController.java`{{execute T3}} + +比如当 user id 小于1时,也正常返回,不抛出异常: + +```java + @GetMapping(value={"/user/{id}"}) + public User findUserById(@PathVariable Integer id) { + logger.info("id: {}", (Object)id); + if (id != null && id < 1) { + return new User(id, "name" + id); + // throw new IllegalArgumentException("id < 1"); + } + return new User(id.intValue(), "name" + id); + } +``` + +### sc查找加载UserController的ClassLoader + +`sc -d *UserController | grep classLoaderHash`{{execute T2}} + +```bash +$ sc -d *UserController | grep classLoaderHash + classLoaderHash 1be6f5c3 +``` + +可以发现是 spring boot `LaunchedURLClassLoader@1be6f5c3` 加载的。 + +请记下你的classLoaderHash,后面需要使用它。在这里,它是 `1be6f5c3`。 + +注意:请使用你的classLoaderHash值覆盖 `` ,然后手动执行下面所有所述命令: + +### mc + +保存好`/tmp/UserController.java`之后,使用`mc`(Memory Compiler)命令来编译,并且通过`-c`参数指定ClassLoader: + +`mc -c /tmp/UserController.java -d /tmp` + +```bash +$ mc -c 1be6f5c3 /tmp/UserController.java -d /tmp +Memory compiler output: +/tmp/com/example/demo/arthas/user/UserController.class +Affect(row-cnt:1) cost in 346 ms +``` + +### redefine + +再使用`redefine`命令重新加载新编译好的`UserController.class`: + +`redefine /tmp/com/example/demo/arthas/user/UserController.class`{{execute T2}} + +``` +$ redefine /tmp/com/example/demo/arthas/user/UserController.class +redefine success, size: 1 +``` + +### 热修改代码结果 + +`redefine`成功之后,再次访问 https://[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com/user/0 ,结果是: + +``` +{ + "id": 0, + "name": "name0" +} +``` diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/finish.md b/tutorials/katacoda/case-jad-mc-redefine-cn/finish.md new file mode 100644 index 000000000..4bbcc13b1 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/finish.md @@ -0,0 +1,10 @@ + +通过本教程基本掌握了Arthas热更新代码。更多高级特性,可以在下面的进阶指南里继续了解。 + +* [Arthas进阶](https://arthas.aliyun.com/doc/arthas-tutorials?language=cn&id=arthas-advanced) +* [Arthas Github](https://github.com/alibaba/arthas) +* [Arthas 文档](https://arthas.aliyun.com/doc/) + +欢迎关注公众号,获取Arthas项目的信息,源码分析,案例实践。 + +![Arthas公众号](/arthas/scenarios/common-resources/assets/qrcode_gongzhonghao.jpg) diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/index.json b/tutorials/katacoda/case-jad-mc-redefine-cn/index.json new file mode 100644 index 000000000..1b88e7039 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/index.json @@ -0,0 +1,45 @@ +{ + "title": "Arthas 热更新代码 案例", + "description": "Arthas 热更新代码 案例", + "difficulty": "高级使用者", + "time": "10分钟", + "details": { + "steps": [ + { + "title": "Start demo", + "text": "start-demo.md" + }, + { + "title": "Start arthas-boot", + "text": "arthas-boot.md" + }, + { + "title": "热更新代码", + "text": "case-jad-mc-redefine.md" + } + ], + "intro": { + "text": "intro.md" + }, + "finish": { + "text": "finish.md" + }, + "assets": { + "host01": [] + } + }, + "environment": { + "uilayout": "terminal", + "showdashboard": true, + "dashboards": [ + { + "name": "Web Port 80", + "port": 80 + } + ] + }, + "backend": { + "imageid": "java", + "environmentsprotocol": "http" + } +} \ No newline at end of file diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/intro.md b/tutorials/katacoda/case-jad-mc-redefine-cn/intro.md new file mode 100644 index 000000000..305296638 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/intro.md @@ -0,0 +1,11 @@ + + + +![Arthas](https://arthas.aliyun.com/doc/_images/arthas.png) + +`Arthas` 是Alibaba开源的Java诊断工具,深受开发者喜爱。在线排查问题,无需重启;动态跟踪Java代码;实时监控JVM状态。 + +`Arthas` 支持JDK 6+,支持Linux/Mac/Windows,采用命令行交互模式,同时提供丰富的 `Tab` 自动补全功能,进一步方便进行问题的定位和诊断。 + +* Github: https://github.com/alibaba/arthas +* 文档: https://arthas.aliyun.com/doc/ \ No newline at end of file diff --git a/tutorials/katacoda/case-jad-mc-redefine-cn/start-demo.md b/tutorials/katacoda/case-jad-mc-redefine-cn/start-demo.md new file mode 100644 index 000000000..59be66ea6 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-cn/start-demo.md @@ -0,0 +1,14 @@ + + + + +下载`demo-arthas-spring-boot.jar`,再用`java -jar`命令启动: + +`wget https://github.com/hengyunabc/spring-boot-inside/raw/master/demo-arthas-spring-boot/demo-arthas-spring-boot.jar +java -jar demo-arthas-spring-boot.jar`{{execute T1}} + +`demo-arthas-spring-boot`是一个很简单的spring boot应用,源代码:[查看](https://github.com/hengyunabc/spring-boot-inside/tree/master/demo-arthas-spring-boot) + +启动之后,可以访问80端口: https://[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com + +![Demo Web](/arthas/scenarios/common-resources/assets/demo-web.png) \ No newline at end of file diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/arthas-boot.md b/tutorials/katacoda/case-jad-mc-redefine-en/arthas-boot.md new file mode 100644 index 000000000..5f6d3f246 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/arthas-boot.md @@ -0,0 +1,16 @@ + + + + +In the new `Terminal 2`, download `arthas-boot.jar` and start with the `java -jar` command: + +`wget https://arthas.aliyun.com/doc/arthas-boot.jar +java -jar arthas-boot.jar`{{execute T2}} + +`arthas-boot` is the launcher for `Arthas`. It lists all the Java processes, and the user can select the target process to be diagnosed. + +Select the first process, type `1`{{execute T2}} ,then type `Enter`: + +After the Attach is successful, Arthas LOGO is printed. Enter `help`{{execute T2}} for more help. + +![Arthas Boot](/arthas/scenarios/common-resources/assets/arthas-boot.png) diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/case-jad-mc-redefine.md b/tutorials/katacoda/case-jad-mc-redefine-en/case-jad-mc-redefine.md new file mode 100644 index 000000000..33468fbf1 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/case-jad-mc-redefine.md @@ -0,0 +1,88 @@ +This case introduces the ability to dynamically update code via the `jad`/`mc`/`redefine` command. + +Currently, visiting http://localhost/user/0 will return a 500 error: + +`curl http://localhost/user/0`{{execute T3}} + +``` +{"timestamp":1550223186170,"status":500,"error":"Internal Server Error","exception":"java.lang.IllegalArgumentException","message":"id < 1","path":"/user/0"} +``` + +This logic will be modified by `redefine` command below. + +### Use jad command to decompile UserController + +`jad --source-only com.example.demo.arthas.user.UserController > /tmp/UserController.java`{{execute T2}} + +The result of jad command will be saved in the `/tmp/UserController.java` file. + + +Then open `Terminal 3`, use `vim` to edit `/tmp/UserController.java`: + +`vim /tmp/UserController.java`{{execute T3}} + +For example, when the user id is less than 1, it also returns normally without throwing an exception: + +```java + @GetMapping(value={"/user/{id}"}) + public User findUserById(@PathVariable Integer id) { + logger.info("id: {}", (Object)id); + if (id != null && id < 1) { + return new User(id, "name" + id); + // throw new IllegalArgumentException("id < 1"); + } + return new User(id.intValue(), "name" + id); + } +``` + +### Use sc command to find the ClassLoader that loads the UserController + +`sc -d *UserController | grep classLoaderHash`{{execute T2}} + +```bash +$ sc -d *UserController | grep classLoaderHash + classLoaderHash 1be6f5c3 +``` + +It can be found that it is loaded by spring boot `LaunchedURLClassLoader@1be6f5c3`. + +Please write down your classLoaderHash here, in the case here, it's `1be6f5c3`. It will be used in the future steps. + +Note: Please replace `` with your classLoaderHash above, then execute the commands manually in the following steps: + +### mc + +After saving `/tmp/UserController.java`, compile with the `mc` (Memory Compiler) command and specify the ClassLoader with the `-c` option: + +`mc -c /tmp/UserController.java -d /tmp` + +```bash +$ mc -c 1be6f5c3 /tmp/UserController.java -d /tmp +Memory compiler output: +/tmp/com/example/demo/arthas/user/UserController.class +Affect(row-cnt:1) cost in 346 ms +``` + +### redefine + +Then reload the newly compiled `UserController.class` with the `redefine` command: + +`redefine /tmp/com/example/demo/arthas/user/UserController.class`{{execute T2}} + +``` +$ redefine /tmp/com/example/demo/arthas/user/UserController.class +redefine success, size: 1 +``` + +### Check the results of the hotswap code + +After the `redefine` command is executed successfully, visit https://[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com/user/0 again. + +The result is: + +``` +{ + "id": 0, + "name": "name0" +} +``` diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/finish.md b/tutorials/katacoda/case-jad-mc-redefine-en/finish.md new file mode 100644 index 000000000..396d9a527 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/finish.md @@ -0,0 +1,6 @@ + +Through this tutorial, you can know how to Hotswap code. More advanced features can be found in the Advanced Guide below. + +* [Arthas Advanced](https://arthas.aliyun.com/doc/arthas-tutorials?language=en&id=arthas-advanced) +* [Arthas Github](https://github.com/alibaba/arthas) +* [Arthas Documentation](https://arthas.aliyun.com/doc/en) diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/index.json b/tutorials/katacoda/case-jad-mc-redefine-en/index.json new file mode 100644 index 000000000..eef3f947d --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/index.json @@ -0,0 +1,45 @@ +{ + "title": "Arthas Hotswap code", + "description": "Arthas Hotswap code", + "difficulty": "expert", + "time": "10 minutes", + "details": { + "steps": [ + { + "title": "Start demo", + "text": "start-demo.md" + }, + { + "title": "Start arthas-boot", + "text": "arthas-boot.md" + }, + { + "title": "Hotswap code", + "text": "case-jad-mc-redefine.md" + } + ], + "intro": { + "text": "intro.md" + }, + "finish": { + "text": "finish.md" + }, + "assets": { + "host01": [] + } + }, + "environment": { + "uilayout": "terminal", + "showdashboard": true, + "dashboards": [ + { + "name": "Web Port 80", + "port": 80 + } + ] + }, + "backend": { + "imageid": "java", + "environmentsprotocol": "http" + } +} \ No newline at end of file diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/intro.md b/tutorials/katacoda/case-jad-mc-redefine-en/intro.md new file mode 100644 index 000000000..c27afd332 --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/intro.md @@ -0,0 +1,11 @@ + + + +![Arthas](https://arthas.aliyun.com/doc/_images/arthas.png) + +`Arthas` is a Java diagnostic tool open-sourced by Alibaba middleware team. Arthas helps developers in trouble-shooting issues in production environment for Java based applications without modifying code or restarting servers. + +`Arthas` supports JDK 6+, supports Linux/Mac/Windows. + +* Github: https://github.com/alibaba/arthas +* Documentation: https://arthas.aliyun.com/doc/en \ No newline at end of file diff --git a/tutorials/katacoda/case-jad-mc-redefine-en/start-demo.md b/tutorials/katacoda/case-jad-mc-redefine-en/start-demo.md new file mode 100644 index 000000000..4915b847a --- /dev/null +++ b/tutorials/katacoda/case-jad-mc-redefine-en/start-demo.md @@ -0,0 +1,14 @@ + + + + +Download `demo-arthas-spring-boot.jar`, and start with `java -jar` command: + +`wget https://github.com/hengyunabc/spring-boot-inside/raw/master/demo-arthas-spring-boot/demo-arthas-spring-boot.jar +java -jar demo-arthas-spring-boot.jar`{{execute T1}} + +`demo-arthas-spring-boot` is a simple Spring Boot demo, the source code here: [View](https://github.com/hengyunabc/spring-boot-inside/tree/master/demo-arthas-spring-boot) + +After booting, access port 80: https://[[HOST_SUBDOMAIN]]-80-[[KATACODA_HOST]].environments.katacoda.com + +![Demo Web](/arthas/scenarios/common-resources/assets/demo-web.png) \ No newline at end of file