feat: Providing Blocking API support for HTTP based services like S3

[Xuanwo]

OpenDAL doesn't provide blocking API support for services like s3 since they depend on tokio and reqwest. However, mostly of our bindings only have blocking API exported which make its hard to integrate with. We should also provide blocking API support for HTTP based services so our users can use those services.

[jiaoew1991]

The implementation of async and blocking in the hdfs backend are just the same. Can other backends' blocking APIs be exactly the same? 🤔 Or are there other better solutions?

[Xuanwo]

I'm thinking about implement a BlockingLayer which will implement Read and Write by forwarding and waiting the output of async API. I will give it a try first.

[jiaoew1991]

I'm thinking about implement a BlockingLayer which will implement Read and Write by forwarding and waiting the output of async API. I will give it a try first.

Looking forward to this implementation.

[chitralverma]

@Xuanwo i was just about to draft an issue for this :)
S3, GCS and AZ should ideally have a blocking API and most other languages have support for this as well.

[jiaoew1991]

Hi，May I ask about the progress of this issue? My colleague has a simple implementation that has been successfully debugged locally. Can we try to merge it in?

[Xuanwo]

Hi，May I ask about the progress of this issue? My colleague has a simple implementation that has been successfully debugged locally. Can we try to merge it in?

Wow, I'm willing to review the PR!