Not support multi pulsar cluster addresses

[hailin0]

Is your feature request related to a problem? Please describe.
not support the use of pulsar cluster addresses?

Describe the solution you'd like

client, err := pulsar.NewClient(pulsar.ClientOptions{
    URL: "pulsar://p1.pulsar.com:6650,pulsar://p2.pulsar.com:6650,pulsar://p3.pulsar.com:6650",
})

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[wolfstudy]

Thanks @hailin0 feedback.

Currently, the go-client not support multi URL in NewClient().

[cgfork]

m

[izackwu]

@wolfstudy

Hi, I'm interested in this issue. But I can't fully understand why multi pulsar cluster addresses are needed for a client.

In Pulsar's doc, service discovery section, I find that

Clients connecting to Pulsar brokers need to be able to communicate with an entire Pulsar instance using a single URL.

So why do we need multi cluster addresses in the client?

[ernado]

I was following this documentation:
http://pulsar.apache.org/docs/en/deploy-bare-metal/

There is

brokerServiceurl=pulsar://host1:6650,host2:6650,host3:6650

Tried there with go client and got error:

dial tcp: address 10.0.0.4:6650,10.0.0.5:6650,10.0.0.3:6650: too many colons in address

So we need multiple addresses to support high availability deployments without DNS.