Add GSLB external plugin

[dmachard]

"I added the GSLB external plugin, which enhances CoreDNS with global server load balancing (GSLB) capabilities. This allows CoreDNS to function similarly to a BigIP F5 GSLB or similar, for example. For more details, see the description at https://github.com/dmachard/coredns-gslb#readme.

[dmachard]

@chrisohaver
Hi,
Any chance to have this pull request merged or I need to do something more ?
Thanks for the great CoreDNS
Denis

[SuperQ]

It doesn't look like there are any semver releases/tags for this codebase. It's nicer for users if there are releases that they can use to get updates.

[dmachard]

It's done,
Thanks for the feedback.

[SuperQ]

Looking over the design, I'm not sure I'm a fan of the external yaml configuration. Why not make all parameters part of the Corefile?

[dmachard]

In fact, I chose to handle GSLB records the same way as the DB zone file (using external files) but in YAML format.

In a real configuration, there can be a large number of records to configure, so I'm not sure it's a good idea to put them directly in the Corefile.

You can find a basic example of how to define a record here:
https://github.com/dmachard/coredns-gslb/blob/main/coredns/gslb_config.example.com.yml

[dmachard]

What to do next ? No more info exists in https://coredns.io/2017/07/23/add-external-plugins/