Add support for "Host" header in custom headers

[Paweł Pierścionek]

Problem

There are use cases where one needs algod/indexer client to dial a different IP than the one resolved from hostname
(aka fake hostname)

This should be possible by providing IP address as a hostname and a custom 'host' header when initializing the Client.

Unfortunately this does not work in Golang as it historically ignores header with Key == 'host'
See this golang issue

Solution

While adding custom headers to a request check if lowercased header key equals to 'host' and set req.Host to the header value.

Dependencies

none

Urgency

none

[Will Winder]

Would this be solved by using a second client pointing to the other server?

[Patrick Bennett]

What is the use case though? Couldn't this normally be handled by local DNS or hosts entries ?

[Paweł Pierścionek]

In my case I need to dial the same url like "mainnet-api.algonode.cloud" but each time to point to a different IP address.
With curl this is the equivalent of curl -H "Host: mainnet-api.algonode.cloud" http://my-real-node-ip
But I would love to be able to do that with SDK so I can write an automated testing tool.