chore(updater): incorporate FetchServers method in Provider interface

- Each provider interface can now fetch updated servers data
- Rename each provider updater subpackage name to `updater`
- Updater constructor does not take a settings struct
- Updater update method takes in a slice of provider strings

internal/provider/mullvad/connection_test.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"math/rand"
 	"net"
+	"net/http"
 	"testing"
 
 	"github.com/golang/mock/gomock"
@@ -96,7 +97,8 @@ func Test_Provider_GetConnection(t *testing.T) {
 				Return(testCase.filteredServers, testCase.storageErr)
 			randSource := rand.NewSource(0)
 
-			provider := New(storage, randSource)
+			client := (*http.Client)(nil)
+			provider := New(storage, randSource, client)
 
 			connection, err := provider.GetConnection(testCase.selection)
 

internal/provider/mullvad/provider.go

@@ -2,9 +2,11 @@ package mullvad
 
 import (
 	"math/rand"
+	"net/http"
 
 	"github.com/qdm12/gluetun/internal/constants/providers"
 	"github.com/qdm12/gluetun/internal/provider/common"
+	"github.com/qdm12/gluetun/internal/provider/mullvad/updater"
 	"github.com/qdm12/gluetun/internal/provider/utils"
 )
 
@@ -12,13 +14,16 @@ type Provider struct {
 	storage    common.Storage
 	randSource rand.Source
 	utils.NoPortForwarder
+	common.Fetcher
 }
 
-func New(storage common.Storage, randSource rand.Source) *Provider {
+func New(storage common.Storage, randSource rand.Source,
+	client *http.Client) *Provider {
 	return &Provider{
 		storage:         storage,
 		randSource:      randSource,
 		NoPortForwarder: utils.NewNoPortForwarding(providers.Mullvad),
+		Fetcher:         updater.New(client),
 	}
 }
 

internal/provider/mullvad/updater/api.go

@@ -1,4 +1,4 @@
-package mullvad
+package updater
 
 import (
 	"context"

internal/provider/mullvad/updater/hosttoserver.go

@@ -1,4 +1,4 @@
-package mullvad
+package updater
 
 import (
 	"errors"

internal/provider/mullvad/updater/ips.go

@@ -1,4 +1,4 @@
-package mullvad
+package updater
 
 import (
 	"bytes"

internal/provider/mullvad/updater/ips_test.go

@@ -1,4 +1,4 @@
-package mullvad
+package updater
 
 import (
 	"net"

internal/provider/mullvad/updater/servers.go

@@ -1,6 +1,6 @@
-// Package mullvad contains code to obtain the server information
+// Package updater contains code to obtain the server information
 // for the Mullvad provider.
-package mullvad
+package updater
 
 import (
 	"context"

internal/provider/mullvad/updater/updater.go

@@ -1,4 +1,4 @@
-package mullvad
+package updater
 
 import (
 	"net/http"