externaldns

This lib implenments External-DNS webhook interface. External-DNS uses this interface to communicate with non-built-in DNS service provider.

The first thing to care is:

trait Provider {
    async fn domain_filter(&self) -> Result<DomainFilter>;
    async fn records(&self) -> Result<Vec<Endpoint>>;
    async fn apply_changes(&self, changes: Changes) -> Result<()>;
    async fn adjust_endpoints(&self, endpoints: Vec<Endpoint>) -> Result<Vec<Endpoint>> {
        Ok(endpoints)
    }
}

The implementor must implement the first three functioons.

domain_filter tells External-DNS the rules to match the domains that this provider takes care.

records tells External-DNS all records the provider currently solves.

External-DNS tells apply_changes what (records) to CUD.

With this implementor, and an optional Status implementor, one can Webhook::new() to get a Webhook instance, then Webhook::start() to get everything working.

For more reference, please checkout the example, which is a fully functioned provider for DNSMasq, which I am using in my K3S.

Ref: webhook-provider.md