Issue 1:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.(I didn't see the file)

Environment

Nacos: 1.2.1

SpringBoot version: 2.2.6

SpringCloudAlibaba: 2.2.1

Dubbo version: 2.7.6

Operating System version: Windows 10

Java version: 1.8

Steps to reproduce this issue

Config the bootstrap.properties of srv1

spring.application.name=srv1-service
spring.main.allow-bean-definition-overriding=true
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
spring.cloud.nacos.discovery.namespace=b50580e2-67d2-4903-b291-27323aa3adaf
spring.cloud.nacos.discovery.group=test

Config application.properties of srv1

server.port=9001
management.endpoints.web.exposure.include=*

dubbo.protocol.name=dubbo
dubbo.registry.address=spring-cloud://localhost
dubbo.consumer.check=false
dubbo.protocol.port=29001
dubbo.scan.base-packages=cn.cnscoo.scatest.srv1.apimpl
dubbo.cloud.subscribed-services=srv2-service
dubbo.application.qos-enable=true
dubbo.application.qos-port=19001

Config another service named srv2 same as srv1 except ports, and them subscribed each other.

Startup both services.

The mutual invocation of services is normal.

Connect the dubbo telnet or qos telnet and execute ls (ls -l)

Expected Result

Qos:

As Provider side:

+-----------------------------------------------------------------------+---+

| Provider Service Name |PUB|

+-----------------------------------------------------------------------+---+

|srv2-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0| Y |

+-----------------------------------------------------------------------+---+

| cn.cnscoo.scatest.srv2.api.Srv2Api | Y |

+-----------------------------------------------------------------------+---+

As Consumer side:

+-----------------------------------------------------------------------+---+

| Consumer Service Name |NUM|

+-----------------------------------------------------------------------+---+

| cn.cnscoo.scatest.srv1.api.Srv1Api | 1 |

+-----------------------------------------------------------------------+---+

|srv1-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0| 1 |

+-----------------------------------------------------------------------+---+

Dubbo:

PROVIDER:

srv2-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0 -> published: Y

cn.cnscoo.scatest.srv2.api.Srv2Api -> published: Y

CONSUMER:

cn.cnscoo.scatest.srv1.api.Srv1Api -> addresses: 1srv1-

service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0 -> addresses: 1

Actual Result

Qos:

As Provider side:

+-----------------------------------------------------------------------+---+

| Provider Service Name |PUB|

+-----------------------------------------------------------------------+---+

|srv2-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0| N |

+-----------------------------------------------------------------------+---+

| cn.cnscoo.scatest.srv2.api.Srv2Api | N |

+-----------------------------------------------------------------------+---+

As Consumer side:

+-----------------------------------------------------------------------+---+

| Consumer Service Name |NUM|

+-----------------------------------------------------------------------+---+

| cn.cnscoo.scatest.srv1.api.Srv1Api | 0 |

+-----------------------------------------------------------------------+---+

|srv1-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0| 0 |

+-----------------------------------------------------------------------+---+

Dubbo:

PROVIDER:

srv2-service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0 -> published: N

cn.cnscoo.scatest.srv2.api.Srv2Api -> published: N

CONSUMER:

cn.cnscoo.scatest.srv1.api.Srv1Api -> addresses: 0srv1-

service/com.alibaba.cloud.dubbo.service.DubboMetadataService:1.0.0 -> addresses: 0

Question

Why I can't get the number of online services?

I find this was not a problem in version 2.7.4.1.

Issue 2:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Steps to reproduce this issue

提交PR，Travis CI build failed，原因为单元测试不通过

单元测试要求直接报异常

5月1号解决[#5916]时，将默认方法修改了，现在不会报异常出来

Pls. provide [GitHub address] to reproduce this issue.

Expected Result

Travis CI build 可以通过