Add schema logic in producer and consumer

[wolfstudy]

Signed-off-by: xiaolong.ran rxl@apache.org

Fixes #344

Motivation

Type safety is extremely important in any application built around a message bus like Pulsar. Currently, Apache Pulsar supports the function of Schema Registry. And Java, CPP and Python clients already support schema registry related functions, In order to further improve the function of Go Client, we need to support the function of Schema Registry in Go Client.

Modifications

• Add schema logic in producer
• Add schema logic in consumer
• Package basic tool functions for schema logic

---

Currente state

• Encapsulates all basic types of decode and encode logic
• Encapsulates the use of all schema types
• A new interface has been added for producer and consumer to be compatible with schema functions

[wolfstudy]

@merlimat @cckellogg PTAL thanks.

[cckellogg]

I think this PR should be split into 2. First add the structs/interfaces for the schema and then add a follow up PR to implement the schema in the client. This will keep the PRs more self contained and easier to review.

[skyrocknroll]

@wolfstudy is there any specific reason why we are using v1.0.5 of goavro ? According to README "github.com/linkedin/goavro/v2" has better support for namespaces and performance improvements. Can we please switch to v2 ?

[wolfstudy]

@wolfstudy is there any specific reason why we are using v1.0.5 of goavro ? According to README "github.com/linkedin/goavro/v2" has better support for namespaces and performance improvements. Can we please switch to v2 ?

Cool, I think we can update the goavro to v2, this looks good to me

[wolfstudy]

@skyrocknroll done PTAL again, thanks.

ping @sijie @massakam If time is convenient, please review it, thanks.

[jiazhai]

lgtm