- `CacheControl.FlushCaches`
- `Querier.Query`
- `Resolver.Resolve`
Besides all the API churn, this leads to `ParallelBestResolver`,
`StrictResolver` and `UpstreamResolver` simplification: timeouts only
need to be setup in one place, `UpstreamResolver`.
We also benefit from using HTTP request contexts, so if the client
closes the connection we stop processing on our side.
* refactor: make `config.Duration` a struct with `time.Duration` embed
Allows directly calling `time.Duration` methods.
* refactor(HostsFileResolver): don't copy individual config items
The idea is to make adding configuration options easier, and searching
for references straight forward.
* refactor: move config printing to struct and use a logger
Using a logger allows using multiple levels so the whole configuration
can be printed in trace/verbose mode, but only important parts are
shown by default.
* squash: rename `Cast` to `ToDuration`
* squash: revert `Duration` to a simple wrapper ("new type" pattern)
* squash: `Duration.IsZero` tests
* squash: refactor resolvers to rely on their config directly if possible
* squash: implement `IsEnabled` and `LogValues` for all resolvers
* refactor: use go-enum `--values` to simplify getting all log fields
* refactor: simplify `QType` unmarshaling
* squash: rename `ValueLogger` to `Configurable`
* squash: rename `UpstreamConfig` to `ParallelBestConfig`
* squash: rename `RewriteConfig` to `RewriterConfig`
* squash: config tests
* squash: resolver tests
* squash: add `ForEach` test and improve `Chain` ones
* squash: simplify implementing `config.Configurable`
* squash: minor changes for better coverage
* squash: more `UnmarshalYAML` -> `UnmarshalText`
* refactor: move `config.Upstream` into own file
* refactor: add `Resolver.Type` method
* squash: add `log` method to `typed` to use `Resolover.Type` as prefix
* squash: tweak startup config logging
* squash: add `LogResolverConfig` tests
* squash: make sure all options of type `Duration` use `%s`
Unify the hosts file parsing between the hosts resolver and lists so
the resolver supports more data sources than local files.
Lists' group cache is now re-used if refresh fails.
Also improve lookups in hosts:
Instead of iterating through all hosts+aliases for each A/AAAA query,
we can do a single lookup.
For PTR we search through only the hosts with an IP version that matches
the question. And compare IPs instead of building the reverse DNS name
for each IP in the hosts database.