chore(updater): create resolver in provider updater

- Pass min servers to resolve call
- Set settings when constructing resolver
- Construct resolver in each provider updater
- No more common resolver for all providers

internal/provider/expressvpn/updater/resolve.go

@@ -1,16 +1,12 @@
 package expressvpn
 
 import (
-	"context"
-	"net"
 	"time"
 
 	"github.com/qdm12/gluetun/internal/updater/resolver"
 )
 
-func resolveHosts(ctx context.Context, presolver resolver.Parallel,
-	hosts []string, minServers int) (hostToIPs map[string][]net.IP,
-	warnings []string, err error) {
+func newParallelResolver() resolver.Parallel {
 	const (
 		maxFailRatio = 0.1
 		maxNoNew     = 1
@@ -18,7 +14,6 @@ func resolveHosts(ctx context.Context, presolver resolver.Parallel,
 	)
 	settings := resolver.ParallelSettings{
 		MaxFailRatio: maxFailRatio,
-		MinFound:     minServers,
 		Repeat: resolver.RepeatSettings{
 			MaxDuration: time.Second,
 			MaxNoNew:    maxNoNew,
@@ -26,5 +21,5 @@ func resolveHosts(ctx context.Context, presolver resolver.Parallel,
 			SortIPs:     true,
 		},
 	}
-	return presolver.Resolve(ctx, hosts, settings)
+	return resolver.NewParallelResolver(settings)
 }

internal/provider/expressvpn/updater/servers.go

@@ -21,7 +21,7 @@ func (u *Updater) FetchServers(ctx context.Context, minServers int) (
 		hosts[i] = servers[i].Hostname
 	}
 
-	hostToIPs, warnings, err := resolveHosts(ctx, u.presolver, hosts, minServers)
+	hostToIPs, warnings, err := u.presolver.Resolve(ctx, hosts, minServers)
 	for _, warning := range warnings {
 		u.warner.Warn(warning)
 	}

internal/provider/expressvpn/updater/updater.go

@@ -15,11 +15,10 @@ type Warner interface {
 	Warn(s string)
 }
 
-func New(unzipper unzip.Unzipper, presolver resolver.Parallel,
-	warner Warner) *Updater {
+func New(unzipper unzip.Unzipper, warner Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
-		presolver: presolver,
+		presolver: newParallelResolver(),
 		warner:    warner,
 	}
 }