Sentinel 1.6.3 resource tree display is incorrect

[eacdy]

测试代码：

@RestController
@Slf4j
public class TestController {
    @Autowired
    private TestService testService;

    @GetMapping("/test-a")
    @SentinelResource(value = "test-a")
    public String testA() {
        return this.testService.common() + "a";
    }

    @GetMapping("/test-b")
    @SentinelResource(value = "test-b")
    public String testB() {
        return this.testService.common() + "b";
    }
}

@Service
class TestService {
    @SentinelResource(value = "common")
    public String common() {
        return "common";
    }
}

复现步骤：

• 依次访问 /test-a、/test-b端点。
• 然后查看localhost:8719/tree

Sentinel 1.6.3 tree端点展示如下：

EntranceNode: machine-root(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: sentinel_web_servlet_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
---test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
---test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: sentinel_default_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)


t:threadNum  pq:passQps  bq:blockQps  tq:totalQps  rt:averageRt  prq: passRequestQps 1mp:1m-pass 1mb:1m-block 1mt:1m-total

可以看到，common资源不会挂到test-b下面去。

换用Sentinel 1.5.2 tree端点展示如下：

EntranceNode: machine-root(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:28 1mb:0 1mt:28)
-EntranceNode: /test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
--/test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
---test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
-EntranceNode: sentinel_default_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: /favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:11 1mb:0 1mt:11)
--/favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:11 1mb:0 1mt:11)
-EntranceNode: /test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
--/test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
---test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)


t:threadNum  pq:passQps  bq:blockQps  tq:totalQps  rt:averageRt  prq: passRequestQps 1mp:1m-pass 1mb:1m-block 1mt:1m-total

于是，Sentinel Dashboard上展示也不对，我觉得是Sentinel 1.6.3的Bug，帮忙修正下。

[sentinel-bot]

Hi @eacdy, we detect non-English characters in the issue. This comment is an auto translation from @sentinel-bot to help other users to understand this issue.
We encourage you to describe your issue in English which is more friendly to other users.

Sentinel 1.6.3 resource tree display is incorrect

@RestController
@Slf4j
public class TestController {
    @Autowired
    private TestService testService;

    @GetMapping("/test-a")
    @SentinelResource(value = "test-a")
    public String testA() {
        return this.testService.common() + "a";
    }

    @GetMapping("/test-b")
    @SentinelResource(value = "test-b")
    public String testB() {
        return this.testService.common() + "b";
    }
}

@Service
class TestService {
    @SentinelResource(value = "common")
    public String common() {
        return "common";
    }
}

Recurring steps:

• Access the /test-a, /test-b endpoints in turn.
• Then check localhost:8719/tree

The Sentinel 1.6.3 tree endpoint is shown below:

EntranceNode: machine-root(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: sentinel_web_servlet_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
---test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
--/test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
---test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: sentinel_default_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)


t:threadNum  pq:passQps  bq:blockQps  tq:totalQps  rt:averageRt  prq: passRequestQps 1mp:1m-pass 1mb:1m-block 1mt:1m-total

** It can be seen that the common resource will not hang under test-b. **

Switching to the Sentinel 1.5.2 tree endpoint is shown below:

EntranceNode: machine-root(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:28 1mb:0 1mt:28)
-EntranceNode: /test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
--/test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
---test-b(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:7 1mb:0 1mt:7)
-EntranceNode: sentinel_default_context(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:0 1mb:0 1mt:0)
-EntranceNode: /favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:11 1mb:0 1mt:11)
--/favicon.ico(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:11 1mb:0 1mt:11)
-EntranceNode: /test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
--/test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
---test-a(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)
----common(t:0 pq:0.0 bq:0.0 tq:0.0 rt:0.0 prq:0.0 1mp:10 1mb:0 1mt:10)


t:threadNum  pq:passQps  bq:blockQps  tq:totalQps  rt:averageRt  prq: passRequestQps 1mp:1m-pass 1mb:1m-block 1mt:1m-total

So, the Sentinel Dashboard is not showing up, I think it is a bug in Sentinel 1.6.3, help me fix it.

[sczyh30]

Sentinel 1.6.3 开始，Web Servlet filter 不再以每个 URL 作为 context，而是统一一个 sentinel_web_servlet_context，以防止 URL 数目过多导致 context EntranceNode 数目爆炸。由于只有一个 context，因此调用链中每个资源只会出现一次。

[eacdy]

@sczyh30

我看了下源码，主要是com.alibaba.csp.sentinel.adapter.servlet.CommonFilter#doFilter 里面，

ContextUtil.enter(WebServletConfig.WEB_SERVLET_CONTEXT_NAME, origin);
这一行导致的。早先的版本，传的是
ContextUtil.enter(target, origin);

但现在，common这个资源，配置链路限流规则，入口为test-a不会生效啊。 现在要怎么解决？

[sczyh30]

目前的 workaround 是在这个 filter 之前自行执行 ContextUtil.enter(target, origin)。

[eacdy]

以上面的代码为例，我应该怎么玩？
自己额外写个过滤器，在CommonFilter之前执行，里面写上 ContextUtil.enter(target, origin)吗？

[sczyh30]

以上面的代码为例，我应该怎么玩？
自己额外写个过滤器，在CommonFilter之前执行，里面写上 ContextUtil.enter(target, origin)吗？

是的，在前面的 filter 包上 ContextUtil#enter 和 exit。

[sczyh30]

Has this been resolved?

[eacdy]

@sczyh30 Never. 如果我需要自己额外加enter/exit，额外写过滤器，那又何必用CommonFilter？我干脆不用CommonFilter，直接自己写也不难。

我觉得合适的解决方案，应该是交给用户去配置。比如在CommonFilter里面加个配置，由使用者自己取决定。

[sczyh30]

@sczyh30 Never. 如果我需要自己额外加enter/exit，额外写过滤器，那又何必用CommonFilter？我干脆不用CommonFilter，直接自己写也不难。

我觉得合适的解决方案，应该是交给用户去配置。比如在CommonFilter里面加个配置，由使用者自己取决定。

Good idea. Would you like to contribute a PR?