聊聊dubbo-go-proxy的ZookeeperRegistryLoad

Posted 2021-10-05 codecraft

序

本文主要研究一下dubbo-go-proxy的ZookeeperRegistryLoad

Loader

dubbo-go-proxy/pkg/registry/load.go

// Loader this interface defined for load services from different kinds registry, such as nacos,consul,zookeeper.
type Loader interface {
    // LoadAllServices load all services registered in registry
    LoadAllServices() ([]*common.URL, error)
    // GetCluster get the registry name
    GetCluster() (string, error)
}

Loader接口定义了LoadAllServices、GetCluster方法

ZookeeperRegistryLoad

dubbo-go-proxy/pkg/registry/zookeeper.go

const (
    rootPath = "/dubbo"
)

func init() {
    var _ Loader = new(ZookeeperRegistryLoad)
}

// ZookeeperRegistryLoad load dubbo apis from zookeeper registry
type ZookeeperRegistryLoad struct {
    zkName  string
    client  *zookeeper.ZookeeperClient
    Address string
    cluster string
}

func newZookeeperRegistryLoad(address, cluster string) (Loader, error) {
    newClient, err := zookeeper.NewZookeeperClient("zkClient", strings.Split(address, ","), 15*time.Second)
    if err != nil {
        logger.Warnf("newZookeeperClient error:%v", err)
        return nil, err
    }

    r := &ZookeeperRegistryLoad{
        Address: address,
        client:  newClient,
        cluster: cluster,
    }

    return r, nil
}

ZookeeperRegistryLoad定义了zkName、client、Address、cluster属性；newZookeeperRegistryLoad根据address及cluster来创建ZookeeperRegistryLoad

GetCluster

dubbo-go-proxy/pkg/registry/zookeeper.go

// nolint
func (crl *ZookeeperRegistryLoad) GetCluster() (string, error) {
    return crl.cluster, nil
}

GetCluster方法返回cluster属性

LoadAllServices

dubbo-go-proxy/pkg/registry/zookeeper.go

// LoadAllServices load all services from zookeeper registry
func (crl *ZookeeperRegistryLoad) LoadAllServices() ([]*common.URL, error) {
    children, err := crl.client.GetChildren(rootPath)
    if err != nil {
        logger.Errorf("[zookeeper registry] get zk children error:%v", err)
        return nil, err
    }
    var urls []*common.URL
    for _, _interface := range children {
        providerStr := path.Join(rootPath, "/", _interface, "/", "providers")
        urlStrs, err := crl.client.GetChildren(providerStr)
        if err != nil {
            logger.Errorf("[zookeeper registry] get zk children \\"%s\\" error:%v", providerStr, err)
            return nil, err
        }
        for _, url := range urlStrs {
            dubboURL, err := common.NewURL(url)
            if err != nil {
                logger.Warnf("[zookeeper registry] transfer zk info to url error:%v", err)
                continue
            }
            urls = append(urls, dubboURL)
        }
    }
    return urls, nil
}

LoadAllServices通过client.GetChildren(rootPath)获取children，之后遍历children，挨个获取provider信息通过common.NewURL(url)构建dubboURL

小结

ZookeeperRegistryLoad定义了zkName、client、Address、cluster属性；newZookeeperRegistryLoad根据address及cluster来创建ZookeeperRegistryLoad；它实现了Loader接口，提供了GetCluster、LoadAllServices方法。

doc

• dubbo-go-proxy