chore(all): return concrete types, accept interfaces

- Remove exported interfaces unused locally
- Define interfaces to accept arguments
- Return concrete types, not interfaces

cmd/gluetun/main.go

@@ -126,8 +126,8 @@ var (
 //nolint:gocognit,gocyclo,maintidx
 func _main(ctx context.Context, buildInfo models.BuildInformation,
 	args []string, logger log.LoggerInterface, source sources.Source,
-	tun tun.Interface, netLinker netlink.NetLinker, cmder command.RunStarter,
-	cli cli.CLIer) error {
+	tun Tun, netLinker netLinker, cmder command.RunStarter,
+	cli clier) error {
 	if len(args) > 1 { // cli operation
 		switch args[1] {
 		case "healthcheck":
@@ -390,7 +390,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 		"vpn", goroutine.OptionTimeout(time.Second))
 	go vpnLooper.Run(vpnCtx, vpnDone)
 
-	updaterLooper := updater.NewLooper(allSettings.Updater,
+	updaterLooper := updater.NewLoop(allSettings.Updater,
 		providers, storage, httpClient, updaterLogger)
 	updaterHandler, updaterCtx, updaterDone := goshutdown.NewGoRoutineHandler(
 		"updater", goroutine.OptionTimeout(defaultShutdownTimeout))
@@ -411,7 +411,7 @@ func _main(ctx context.Context, buildInfo models.BuildInformation,
 	go httpProxyLooper.Run(httpProxyCtx, httpProxyDone)
 	otherGroupHandler.Add(httpProxyHandler)
 
-	shadowsocksLooper := shadowsocks.NewLooper(allSettings.Shadowsocks,
+	shadowsocksLooper := shadowsocks.NewLoop(allSettings.Shadowsocks,
 		logger.New(log.SetComponent("shadowsocks")))
 	shadowsocksHandler, shadowsocksCtx, shadowsocksDone := goshutdown.NewGoRoutineHandler(
 		"shadowsocks proxy", goroutine.OptionTimeout(defaultShutdownTimeout))
@@ -480,3 +480,38 @@ func printVersions(ctx context.Context, logger infoer,
 
 	return nil
 }
+
+type netLinker interface {
+	AddrList(link netlink.Link, family int) (
+		addresses []netlink.Addr, err error)
+	AddrAdd(link netlink.Link, addr *netlink.Addr) error
+	IsWireguardSupported() (ok bool, err error)
+	RouteList(link netlink.Link, family int) (
+		routes []netlink.Route, err error)
+	RouteAdd(route *netlink.Route) error
+	RouteDel(route *netlink.Route) error
+	RouteReplace(route *netlink.Route) error
+	RuleList(family int) (rules []netlink.Rule, err error)
+	RuleAdd(rule *netlink.Rule) error
+	RuleDel(rule *netlink.Rule) error
+	LinkList() (links []netlink.Link, err error)
+	LinkByName(name string) (link netlink.Link, err error)
+	LinkByIndex(index int) (link netlink.Link, err error)
+	LinkAdd(link netlink.Link) (err error)
+	LinkDel(link netlink.Link) (err error)
+	LinkSetUp(link netlink.Link) (err error)
+	LinkSetDown(link netlink.Link) (err error)
+}
+
+type clier interface {
+	ClientKey(args []string) error
+	FormatServers(args []string) error
+	OpenvpnConfig(logger cli.OpenvpnConfigLogger, source sources.Source) error
+	HealthCheck(ctx context.Context, source sources.Source, warner cli.Warner) error
+	Update(ctx context.Context, args []string, logger cli.UpdaterLogger) error
+}
+
+type Tun interface {
+	Check(tunDevice string) error
+	Create(tunDevice string) error
+}

internal/alpine/alpine.go

@@ -5,13 +5,6 @@ import (
 	"os/user"
 )
 
-var _ Alpiner = (*Alpine)(nil)
-
-type Alpiner interface {
-	UserCreater
-	VersionGetter
-}
-
 type Alpine struct {
 	alpineReleasePath string
 	passwdPath        string

internal/alpine/users.go

@@ -12,10 +12,6 @@ var (
 	ErrUserAlreadyExists = errors.New("user already exists")
 )
 
-type UserCreater interface {
-	CreateUser(username string, uid int) (createdUsername string, err error)
-}
-
 // CreateUser creates a user in Alpine with the given UID.
 func (a *Alpine) CreateUser(username string, uid int) (createdUsername string, err error) {
 	UIDStr := strconv.Itoa(uid)

internal/alpine/version.go

@@ -7,10 +7,6 @@ import (
 	"strings"
 )
 
-type VersionGetter interface {
-	Version(ctx context.Context) (version string, err error)
-}
-
 func (a *Alpine) Version(ctx context.Context) (version string, err error) {
 	file, err := os.OpenFile(a.alpineReleasePath, os.O_RDONLY, 0)
 	if err != nil {

internal/cli/cli.go

@@ -1,16 +1,6 @@
 // Package cli defines an interface CLI to run command line operations.
 package cli
 
-var _ CLIer = (*CLI)(nil)
-
-type CLIer interface {
-	ClientKeyFormatter
-	HealthChecker
-	OpenvpnConfigMaker
-	Updater
-	ServersFormatter
-}
-
 type CLI struct {
 	repoServersPath string
 }

internal/cli/clientkey.go

@@ -10,10 +10,6 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/sources/files"
 )
 
-type ClientKeyFormatter interface {
-	ClientKey(args []string) error
-}
-
 func (c *CLI) ClientKey(args []string) error {
 	flagSet := flag.NewFlagSet("clientkey", flag.ExitOnError)
 	filepath := flagSet.String("path", files.OpenVPNClientKeyPath, "file path to the client.key file")

internal/cli/formatservers.go

@@ -15,10 +15,6 @@ import (
 	"golang.org/x/text/language"
 )
 
-type ServersFormatter interface {
-	FormatServers(args []string) error
-}
-
 var (
 	ErrFormatNotRecognized       = errors.New("format is not recognized")
 	ErrProviderUnspecified       = errors.New("VPN provider to format was not specified")

internal/cli/healthcheck.go

@@ -10,10 +10,6 @@ import (
 	"github.com/qdm12/gluetun/internal/healthcheck"
 )
 
-type HealthChecker interface {
-	HealthCheck(ctx context.Context, source sources.Source, warner Warner) error
-}
-
 func (c *CLI) HealthCheck(ctx context.Context, source sources.Source, warner Warner) error {
 	// Extract the health server port from the configuration.
 	config, err := source.ReadHealth()

internal/cli/openvpnconfig.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 	"strings"
@@ -10,18 +11,18 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/provider"
 	"github.com/qdm12/gluetun/internal/storage"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
-type OpenvpnConfigMaker interface {
-	OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) error
-}
-
 type OpenvpnConfigLogger interface {
 	Info(s string)
 	Warn(s string)
 }
 
+type Unzipper interface {
+	FetchAndExtract(ctx context.Context, url string) (
+		contents map[string][]byte, err error)
+}
+
 func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) error {
 	storage, err := storage.New(logger, constants.ServersData)
 	if err != nil {
@@ -38,7 +39,7 @@ func (c *CLI) OpenvpnConfig(logger OpenvpnConfigLogger, source sources.Source) e
 	}
 
 	// Unused by this CLI command
-	unzipper := (unzip.Unzipper)(nil)
+	unzipper := (Unzipper)(nil)
 	client := (*http.Client)(nil)
 	warner := (Warner)(nil)
 

internal/cli/update.go

@@ -25,10 +25,6 @@ var (
 	ErrNoProviderSpecified = errors.New("no provider was specified")
 )
 
-type Updater interface {
-	Update(ctx context.Context, args []string, logger UpdaterLogger) error
-}
-
 type UpdaterLogger interface {
 	Info(s string)
 	Warn(s string)

internal/dns/interfaces.go

@@ -0,0 +1,29 @@
+package dns
+
+import (
+	"context"
+
+	"github.com/qdm12/dns/pkg/unbound"
+	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+)
+
+type Configurator interface {
+	SetupFiles(ctx context.Context) error
+	MakeUnboundConf(settings unbound.Settings) (err error)
+	Start(ctx context.Context, verbosityDetailsLevel uint8) (
+		stdoutLines, stderrLines chan string, waitError chan error, err error)
+	Version(ctx context.Context) (version string, err error)
+}
+
+type statusManager interface {
+	GetStatus() (status models.LoopStatus)
+	SetStatus(status models.LoopStatus)
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}
+
+type stateManager interface {
+	GetSettings() (settings settings.DNS)
+	SetSettings(ctx context.Context, settings settings.DNS) (outcome string)
+}

internal/dns/loop.go

@@ -7,7 +7,6 @@ import (
 	"time"
 
 	"github.com/qdm12/dns/pkg/blacklist"
-	"github.com/qdm12/dns/pkg/unbound"
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/dns/state"
@@ -15,20 +14,10 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Looper = (*Loop)(nil)
-
-type Looper interface {
-	Runner
-	RestartTickerRunner
-	loopstate.Applier
-	loopstate.Getter
-	SettingsGetSetter
-}
-
 type Loop struct {
-	statusManager loopstate.Manager
-	state         state.Manager
-	conf          unbound.Configurator
+	statusManager statusManager
+	state         stateManager
+	conf          Configurator
 	resolvConf    string
 	blockBuilder  blacklist.Builder
 	client        *http.Client
@@ -46,7 +35,7 @@ type Loop struct {
 
 const defaultBackoffTime = 10 * time.Second
 
-func NewLoop(conf unbound.Configurator, settings settings.DNS,
+func NewLoop(conf Configurator, settings settings.DNS,
 	client *http.Client, logger Logger) *Loop {
 	start := make(chan struct{})
 	running := make(chan models.LoopStatus)

internal/dns/run.go

@@ -7,10 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type Runner interface {
-	Run(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 

internal/dns/settings.go

@@ -6,22 +6,8 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-type SettingsGetSetter interface {
-	SettingsGetter
-	SettingsSetter
-}
-
-type SettingsGetter interface {
-	GetSettings() (settings settings.DNS)
-}
-
 func (l *Loop) GetSettings() (settings settings.DNS) { return l.state.GetSettings() }
 
-type SettingsSetter interface {
-	SetSettings(ctx context.Context, settings settings.DNS) (
-		outcome string)
-}
-
 func (l *Loop) SetSettings(ctx context.Context, settings settings.DNS) (
 	outcome string) {
 	return l.state.SetSettings(ctx, settings)

internal/dns/state/settings.go

@@ -8,12 +8,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type SettingsGetSetter interface {
-	GetSettings() (settings settings.DNS)
-	SetSettings(ctx context.Context,
-		settings settings.DNS) (outcome string)
-}
-
 func (s *State) GetSettings() (settings settings.DNS) {
 	s.settingsMu.RLock()
 	defer s.settingsMu.RUnlock()

internal/dns/state/state.go

@@ -1,19 +1,14 @@
 package state
 
 import (
+	"context"
 	"sync"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/loopstate"
+	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Manager = (*State)(nil)
-
-type Manager interface {
-	SettingsGetSetter
-}
-
-func New(statusApplier loopstate.Applier,
+func New(statusApplier StatusApplier,
 	settings settings.DNS,
 	updateTicker chan<- struct{}) *State {
 	return &State{
@@ -24,10 +19,15 @@ func New(statusApplier loopstate.Applier,
 }
 
 type State struct {
-	statusApplier loopstate.Applier
+	statusApplier StatusApplier
 
 	settings   settings.DNS
 	settingsMu sync.RWMutex
 
 	updateTicker chan<- struct{}
 }
+
+type StatusApplier interface {
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}

internal/dns/ticker.go

@@ -7,10 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type RestartTickerRunner interface {
-	RunRestartTicker(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) RunRestartTicker(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 	// Timer that acts as a ticker

internal/firewall/enable.go

@@ -5,10 +5,6 @@ import (
 	"fmt"
 )
 
-type Enabler interface {
-	SetEnabled(ctx context.Context, enabled bool) (err error)
-}
-
 func (c *Config) SetEnabled(ctx context.Context, enabled bool) (err error) {
 	c.stateMutex.Lock()
 	defer c.stateMutex.Unlock()

internal/firewall/firewall.go

@@ -12,16 +12,6 @@ import (
 	"github.com/qdm12/golibs/command"
 )
 
-var _ Configurator = (*Config)(nil)
-
-// Configurator allows to change firewall rules and modify network routes.
-type Configurator interface {
-	Enabler
-	VPNConnectionSetter
-	PortAllower
-	OutboundSubnetsSetter
-}
-
 type Config struct { //nolint:maligned
 	runner         command.Runner
 	logger         Logger

internal/firewall/outboundsubnets.go

@@ -8,10 +8,6 @@ import (
 	"github.com/qdm12/gluetun/internal/subnet"
 )
 
-type OutboundSubnetsSetter interface {
-	SetOutboundSubnets(ctx context.Context, subnets []net.IPNet) (err error)
-}
-
 func (c *Config) SetOutboundSubnets(ctx context.Context, subnets []net.IPNet) (err error) {
 	c.stateMutex.Lock()
 	defer c.stateMutex.Unlock()

internal/firewall/ports.go

@@ -6,11 +6,6 @@ import (
 	"strconv"
 )
 
-type PortAllower interface {
-	SetAllowedPort(ctx context.Context, port uint16, intf string) (err error)
-	RemoveAllowedPort(ctx context.Context, port uint16) (err error)
-}
-
 func (c *Config) SetAllowedPort(ctx context.Context, port uint16, intf string) (err error) {
 	c.stateMutex.Lock()
 	defer c.stateMutex.Unlock()

internal/firewall/vpn.go

@@ -7,11 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-type VPNConnectionSetter interface {
-	SetVPNConnection(ctx context.Context,
-		connection models.Connection, vpnIntf string) error
-}
-
 func (c *Config) SetVPNConnection(ctx context.Context,
 	connection models.Connection, vpnIntf string) (err error) {
 	c.stateMutex.Lock()

internal/healthcheck/client.go

@@ -12,12 +12,6 @@ var (
 	ErrHTTPStatusNotOK = errors.New("HTTP response status is not OK")
 )
 
-var _ Checker = (*Client)(nil)
-
-type Checker interface {
-	Check(ctx context.Context, url string) error
-}
-
 type Client struct {
 	httpClient *http.Client
 }

internal/healthcheck/openvpn.go

@@ -5,11 +5,10 @@ import (
 	"time"
 
 	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/gluetun/internal/vpn"
 )
 
 type vpnHealth struct {
-	looper       vpn.Looper
+	loop         StatusApplier
 	healthyWait  time.Duration
 	healthyTimer *time.Timer
 }
@@ -17,8 +16,8 @@ type vpnHealth struct {
 func (s *Server) onUnhealthyVPN(ctx context.Context) {
 	s.logger.Info("program has been unhealthy for " +
 		s.vpn.healthyWait.String() + ": restarting VPN")
-	_, _ = s.vpn.looper.ApplyStatus(ctx, constants.Stopped)
-	_, _ = s.vpn.looper.ApplyStatus(ctx, constants.Running)
+	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Stopped)
+	_, _ = s.vpn.loop.ApplyStatus(ctx, constants.Running)
 	s.vpn.healthyWait += *s.config.VPN.Addition
 	s.vpn.healthyTimer = time.NewTimer(s.vpn.healthyWait)
 }

internal/healthcheck/server.go

@@ -5,15 +5,9 @@ import (
 	"net"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/vpn"
+	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ ServerRunner = (*Server)(nil)
-
-type ServerRunner interface {
-	Run(ctx context.Context, done chan<- struct{})
-}
-
 type Server struct {
 	logger  Logger
 	handler *handler
@@ -23,15 +17,20 @@ type Server struct {
 }
 
 func NewServer(config settings.Health,
-	logger Logger, vpnLooper vpn.Looper) *Server {
+	logger Logger, vpnLoop StatusApplier) *Server {
 	return &Server{
 		logger:  logger,
 		handler: newHandler(),
 		dialer:  &net.Dialer{},
 		config:  config,
 		vpn: vpnHealth{
-			looper:      vpnLooper,
+			loop:        vpnLoop,
 			healthyWait: *config.VPN.Initial,
 		},
 	}
 }
+
+type StatusApplier interface {
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}

internal/httpproxy/loop.go

@@ -12,18 +12,9 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Looper = (*Loop)(nil)
-
-type Looper interface {
-	Runner
-	loopstate.Getter
-	loopstate.Applier
-	SettingsGetSetter
-}
-
 type Loop struct {
-	statusManager loopstate.Manager
-	state         state.Manager
+	statusManager statusManager
+	state         StateManager
 	// Other objects
 	logger Logger
 	// Internal channels and locks
@@ -34,6 +25,18 @@ type Loop struct {
 	backoffTime   time.Duration
 }
 
+type statusManager interface {
+	GetStatus() (status models.LoopStatus)
+	SetStatus(status models.LoopStatus)
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}
+
+type StateManager interface {
+	GetSettings() settings.HTTPProxy
+	SetSettings(ctx context.Context, settings settings.HTTPProxy) (outcome string)
+}
+
 const defaultBackoffTime = 10 * time.Second
 
 func NewLoop(logger Logger, settings settings.HTTPProxy) *Loop {

internal/httpproxy/run.go

@@ -6,10 +6,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type Runner interface {
-	Run(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 

internal/httpproxy/settings.go

@@ -4,11 +4,8 @@ import (
 	"context"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/httpproxy/state"
 )
 
-type SettingsGetSetter = state.SettingsGetSetter
-
 func (l *Loop) GetSettings() (settings settings.HTTPProxy) {
 	return l.state.GetSettings()
 }

internal/httpproxy/state/settings.go

@@ -8,26 +8,12 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type SettingsGetSetter interface {
-	SettingsGetter
-	SettingsSetter
-}
-
-type SettingsGetter interface {
-	GetSettings() (settings settings.HTTPProxy)
-}
-
 func (s *State) GetSettings() (settings settings.HTTPProxy) {
 	s.settingsMu.RLock()
 	defer s.settingsMu.RUnlock()
 	return s.settings
 }
 
-type SettingsSetter interface {
-	SetSettings(ctx context.Context,
-		settings settings.HTTPProxy) (outcome string)
-}
-
 func (s *State) SetSettings(ctx context.Context,
 	settings settings.HTTPProxy) (outcome string) {
 	s.settingsMu.Lock()

internal/httpproxy/state/state.go

@@ -1,19 +1,14 @@
 package state
 
 import (
+	"context"
 	"sync"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/loopstate"
+	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Manager = (*State)(nil)
-
-type Manager interface {
-	SettingsGetSetter
-}
-
-func New(statusApplier loopstate.Applier,
+func New(statusApplier StatusApplier,
 	settings settings.HTTPProxy) *State {
 	return &State{
 		statusApplier: statusApplier,
@@ -22,7 +17,12 @@ func New(statusApplier loopstate.Applier,
 }
 
 type State struct {
-	statusApplier loopstate.Applier
+	statusApplier StatusApplier
 	settings      settings.HTTPProxy
 	settingsMu    sync.RWMutex
 }
+
+type StatusApplier interface {
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}

internal/httpserver/server.go

@@ -2,30 +2,11 @@
 package httpserver
 
 import (
-	"context"
 	"fmt"
 	"net/http"
 	"time"
 )
 
-var _ Interface = (*Server)(nil)
-
-// Interface is the HTTP server composite interface.
-type Interface interface {
-	Runner
-	AddressGetter
-}
-
-// Runner is the interface for an HTTP server with a Run method.
-type Runner interface {
-	Run(ctx context.Context, ready chan<- struct{}, done chan<- struct{})
-}
-
-// AddressGetter obtains the address the HTTP server is listening on.
-type AddressGetter interface {
-	GetAddress() (address string)
-}
-
 // Server is an HTTP server implementation, which uses
 // the HTTP handler provided.
 type Server struct {

internal/loopstate/apply.go

@@ -9,11 +9,6 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-type Applier interface {
-	ApplyStatus(ctx context.Context, status models.LoopStatus) (
-		outcome string, err error)
-}
-
 var ErrInvalidStatus = errors.New("invalid status")
 
 // ApplyStatus sends signals to the running loop depending on the

internal/loopstate/get.go

@@ -2,10 +2,6 @@ package loopstate
 
 import "github.com/qdm12/gluetun/internal/models"
 
-type Getter interface {
-	GetStatus() (status models.LoopStatus)
-}
-
 // GetStatus gets the status thread safely.
 func (s *State) GetStatus() (status models.LoopStatus) {
 	s.statusMu.RLock()

internal/loopstate/lock.go

@@ -1,9 +1,4 @@
 package loopstate
 
-type Locker interface {
-	Lock()
-	Unlock()
-}
-
 func (s *State) Lock()   { s.loopMu.Lock() }
 func (s *State) Unlock() { s.loopMu.Unlock() }

internal/loopstate/set.go

@@ -2,10 +2,6 @@ package loopstate
 
 import "github.com/qdm12/gluetun/internal/models"
 
-type Setter interface {
-	SetStatus(status models.LoopStatus)
-}
-
 // SetStatus sets the status thread safely.
 // It should only be called by the loop internal code since
 // it does not interact with the loop code directly.

internal/loopstate/state.go

@@ -6,15 +6,6 @@ import (
 	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Manager = (*State)(nil)
-
-type Manager interface {
-	Locker
-	Getter
-	Setter
-	Applier
-}
-
 func New(status models.LoopStatus,
 	start chan<- struct{}, running <-chan models.LoopStatus,
 	stop chan<- struct{}, stopped <-chan struct{}) *State {

internal/netlink/address.go

@@ -4,14 +4,6 @@ import "github.com/vishvananda/netlink"
 
 type Addr = netlink.Addr
 
-var _ Addresser = (*NetLink)(nil)
-
-type Addresser interface {
-	AddrList(link netlink.Link, family int) (
-		addresses []netlink.Addr, err error)
-	AddrAdd(link netlink.Link, addr *netlink.Addr) error
-}
-
 func (n *NetLink) AddrList(link Link, family int) (
 	addresses []Addr, err error) {
 	return netlink.AddrList(link, family)

internal/netlink/family.go

@@ -13,10 +13,6 @@ const (
 	FAMILY_V6  = netlink.FAMILY_V6
 )
 
-type WireguardChecker interface {
-	IsWireguardSupported() (ok bool, err error)
-}
-
 func (n *NetLink) IsWireguardSupported() (ok bool, err error) {
 	families, err := netlink.GenlFamilyList()
 	if err != nil {

internal/netlink/interface.go

@@ -1,13 +0,0 @@
-package netlink
-
-//go:generate mockgen -destination=mock_$GOPACKAGE/$GOFILE . NetLinker
-
-var _ NetLinker = (*NetLink)(nil)
-
-type NetLinker interface {
-	Addresser
-	Linker
-	Router
-	Ruler
-	WireguardChecker
-}

internal/netlink/link.go

@@ -8,18 +8,6 @@ type (
 	Wireguard = netlink.Wireguard
 )
 
-var _ Linker = (*NetLink)(nil)
-
-type Linker interface {
-	LinkList() (links []netlink.Link, err error)
-	LinkByName(name string) (link netlink.Link, err error)
-	LinkByIndex(index int) (link netlink.Link, err error)
-	LinkAdd(link netlink.Link) (err error)
-	LinkDel(link netlink.Link) (err error)
-	LinkSetUp(link netlink.Link) (err error)
-	LinkSetDown(link netlink.Link) (err error)
-}
-
 func (n *NetLink) LinkList() (links []Link, err error) {
 	return netlink.LinkList()
 }

internal/netlink/route.go

@@ -4,16 +4,6 @@ import "github.com/vishvananda/netlink"
 
 type Route = netlink.Route
 
-var _ Router = (*NetLink)(nil)
-
-type Router interface {
-	RouteList(link netlink.Link, family int) (
-		routes []netlink.Route, err error)
-	RouteAdd(route *netlink.Route) error
-	RouteDel(route *netlink.Route) error
-	RouteReplace(route *netlink.Route) error
-}
-
 func (n *NetLink) RouteList(link Link, family int) (
 	routes []Route, err error) {
 	return netlink.RouteList(link, family)

internal/netlink/rule.go

@@ -8,14 +8,6 @@ func NewRule() *Rule {
 	return netlink.NewRule()
 }
 
-var _ Ruler = (*NetLink)(nil)
-
-type Ruler interface {
-	RuleList(family int) (rules []netlink.Rule, err error)
-	RuleAdd(rule *netlink.Rule) error
-	RuleDel(rule *netlink.Rule) error
-}
-
 func (n *NetLink) RuleList(family int) (rules []Rule, err error) {
 	return netlink.RuleList(family)
 }

internal/openvpn/auth.go

@@ -6,10 +6,6 @@ import (
 	"strings"
 )
 
-type AuthWriter interface {
-	WriteAuthFile(user, password string) error
-}
-
 // WriteAuthFile writes the OpenVPN auth file to disk with the right permissions.
 func (c *Configurator) WriteAuthFile(user, password string) error {
 	file, err := os.Open(c.authFilePath)

internal/openvpn/config.go

@@ -5,10 +5,6 @@ import (
 	"strings"
 )
 
-type Writer interface {
-	WriteConfig(lines []string) error
-}
-
 func (c *Configurator) WriteConfig(lines []string) error {
 	file, err := os.OpenFile(c.configPath, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
 	if err != nil {

internal/openvpn/extract/extractor.go

@@ -1,16 +1,5 @@
 package extract
 
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-var _ Interface = (*Extractor)(nil)
-
-type Interface interface {
-	Data(filepath string) (lines []string,
-		connection models.Connection, err error)
-}
-
 type Extractor struct{}
 
 func New() *Extractor {

internal/openvpn/openvpn.go

@@ -5,14 +5,6 @@ import (
 	"github.com/qdm12/golibs/command"
 )
 
-var _ Interface = (*Configurator)(nil)
-
-type Interface interface {
-	VersionGetter
-	AuthWriter
-	Writer
-}
-
 type Configurator struct {
 	logger       Infoer
 	cmder        command.RunStarter

internal/openvpn/version.go

@@ -8,11 +8,6 @@ import (
 	"strings"
 )
 
-type VersionGetter interface {
-	Version24(ctx context.Context) (version string, err error)
-	Version25(ctx context.Context) (version string, err error)
-}
-
 func (c *Configurator) Version24(ctx context.Context) (version string, err error) {
 	return c.version(ctx, binOpenvpn24)
 }

internal/portforward/get.go

@@ -1,9 +1,5 @@
 package portforward
 
-import "github.com/qdm12/gluetun/internal/portforward/state"
-
-type Getter = state.PortForwardedGetter
-
 func (l *Loop) GetPortForwarded() (port uint16) {
 	return l.state.GetPortForwarded()
 }

internal/portforward/interfaces.go

@@ -0,0 +1,30 @@
+package portforward
+
+import (
+	"context"
+
+	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+)
+
+type PortAllower interface {
+	SetAllowedPort(ctx context.Context, port uint16, intf string) (err error)
+	RemoveAllowedPort(ctx context.Context, port uint16) (err error)
+}
+
+type statusManager interface {
+	GetStatus() (status models.LoopStatus)
+	SetStatus(status models.LoopStatus)
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}
+
+type StateManager interface {
+	GetSettings() (settings settings.PortForwarding)
+	SetSettings(ctx context.Context,
+		settings settings.PortForwarding) (outcome string)
+	GetPortForwarded() (port uint16)
+	SetPortForwarded(port uint16)
+	GetStartData() (startData StartData)
+	SetStartData(startData StartData)
+}

internal/portforward/loop.go

@@ -7,28 +7,17 @@ import (
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/gluetun/internal/firewall"
 	"github.com/qdm12/gluetun/internal/loopstate"
 	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/gluetun/internal/portforward/state"
 )
 
-var _ Looper = (*Loop)(nil)
-
-type Looper interface {
-	Runner
-	loopstate.Getter
-	StartStopper
-	SettingsGetSetter
-	Getter
-}
-
 type Loop struct {
-	statusManager loopstate.Manager
-	state         state.Manager
+	statusManager statusManager
+	state         StateManager
 	// Objects
 	client      *http.Client
-	portAllower firewall.PortAllower
+	portAllower PortAllower
 	logger      Logger
 	// Internal channels and locks
 	start       chan struct{}
@@ -43,7 +32,7 @@ type Loop struct {
 const defaultBackoffTime = 5 * time.Second
 
 func NewLoop(settings settings.PortForwarding,
-	client *http.Client, portAllower firewall.PortAllower,
+	client *http.Client, portAllower PortAllower,
 	logger Logger) *Loop {
 	start := make(chan struct{})
 	running := make(chan models.LoopStatus)

internal/portforward/run.go

@@ -7,10 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type Runner interface {
-	Run(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 

internal/portforward/settings.go

@@ -4,11 +4,8 @@ import (
 	"context"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/portforward/state"
 )
 
-type SettingsGetSetter = state.SettingsGetSetter
-
 func (l *Loop) GetSettings() (settings settings.PortForwarding) {
 	return l.state.GetSettings()
 }

internal/portforward/state/portforwarded.go

@@ -1,14 +1,5 @@
 package state
 
-type PortForwardedGetterSetter interface {
-	PortForwardedGetter
-	SetPortForwarded(port uint16)
-}
-
-type PortForwardedGetter interface {
-	GetPortForwarded() (port uint16)
-}
-
 // GetPortForwarded is used by the control HTTP server
 // to obtain the port currently forwarded.
 func (s *State) GetPortForwarded() (port uint16) {

internal/portforward/state/settings.go

@@ -9,12 +9,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type SettingsGetSetter interface {
-	GetSettings() (settings settings.PortForwarding)
-	SetSettings(ctx context.Context,
-		settings settings.PortForwarding) (outcome string)
-}
-
 func (s *State) GetSettings() (settings settings.PortForwarding) {
 	s.settingsMu.RLock()
 	defer s.settingsMu.RUnlock()

internal/portforward/state/startdata.go

@@ -13,25 +13,12 @@ type StartData struct {
 	Interface     string // tun0 for example
 }
 
-type StartDataGetterSetter interface {
-	StartDataGetter
-	StartDataSetter
-}
-
-type StartDataGetter interface {
-	GetStartData() (startData StartData)
-}
-
 func (s *State) GetStartData() (startData StartData) {
 	s.startDataMu.RLock()
 	defer s.startDataMu.RUnlock()
 	return s.startData
 }
 
-type StartDataSetter interface {
-	SetStartData(startData StartData)
-}
-
 func (s *State) SetStartData(startData StartData) {
 	s.startDataMu.Lock()
 	defer s.startDataMu.Unlock()

internal/portforward/state/state.go

@@ -1,21 +1,14 @@
 package state
 
 import (
+	"context"
 	"sync"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/loopstate"
+	"github.com/qdm12/gluetun/internal/models"
 )
 
-var _ Manager = (*State)(nil)
-
-type Manager interface {
-	SettingsGetSetter
-	PortForwardedGetterSetter
-	StartDataGetterSetter
-}
-
-func New(statusApplier loopstate.Applier,
+func New(statusApplier StatusApplier,
 	settings settings.PortForwarding) *State {
 	return &State{
 		statusApplier: statusApplier,
@@ -24,7 +17,7 @@ func New(statusApplier loopstate.Applier,
 }
 
 type State struct {
-	statusApplier loopstate.Applier
+	statusApplier StatusApplier
 
 	settings   settings.PortForwarding
 	settingsMu sync.RWMutex
@@ -35,3 +28,8 @@ type State struct {
 	startData   StartData
 	startDataMu sync.RWMutex
 }
+
+type StatusApplier interface {
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}

internal/portforward/status.go

@@ -14,12 +14,6 @@ func (l *Loop) GetStatus() (status models.LoopStatus) {
 
 type StartData = state.StartData
 
-type StartStopper interface {
-	Start(ctx context.Context, data StartData) (
-		outcome string, err error)
-	Stop(ctx context.Context) (outcome string, err error)
-}
-
 func (l *Loop) Start(ctx context.Context, data StartData) (
 	outcome string, err error) {
 	l.startMu.Lock()

internal/provider/common/mocks.go

@@ -1,5 +1,5 @@
 // Code generated by MockGen. DO NOT EDIT.
-// Source: github.com/qdm12/gluetun/internal/provider/common (interfaces: ParallelResolver,Storage)
+// Source: github.com/qdm12/gluetun/internal/provider/common (interfaces: ParallelResolver,Storage,Unzipper)
 
 // Package common is a generated GoMock package.
 package common
@@ -105,3 +105,41 @@ func (mr *MockStorageMockRecorder) GetServerByName(arg0, arg1 interface{}) *gomo
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetServerByName", reflect.TypeOf((*MockStorage)(nil).GetServerByName), arg0, arg1)
 }
+
+// MockUnzipper is a mock of Unzipper interface.
+type MockUnzipper struct {
+	ctrl     *gomock.Controller
+	recorder *MockUnzipperMockRecorder
+}
+
+// MockUnzipperMockRecorder is the mock recorder for MockUnzipper.
+type MockUnzipperMockRecorder struct {
+	mock *MockUnzipper
+}
+
+// NewMockUnzipper creates a new mock instance.
+func NewMockUnzipper(ctrl *gomock.Controller) *MockUnzipper {
+	mock := &MockUnzipper{ctrl: ctrl}
+	mock.recorder = &MockUnzipperMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use.
+func (m *MockUnzipper) EXPECT() *MockUnzipperMockRecorder {
+	return m.recorder
+}
+
+// FetchAndExtract mocks base method.
+func (m *MockUnzipper) FetchAndExtract(arg0 context.Context, arg1 string) (map[string][]byte, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "FetchAndExtract", arg0, arg1)
+	ret0, _ := ret[0].(map[string][]byte)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// FetchAndExtract indicates an expected call of FetchAndExtract.
+func (mr *MockUnzipperMockRecorder) FetchAndExtract(arg0, arg1 interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "FetchAndExtract", reflect.TypeOf((*MockUnzipper)(nil).FetchAndExtract), arg0, arg1)
+}

internal/provider/common/mocks_generate_test.go

@@ -2,4 +2,4 @@ package common
 
 // Exceptionally, these mocks are exported since they are used by all
 // provider subpackages tests, and it reduces test code duplication a lot.
-//go:generate mockgen -destination=mocks.go -package $GOPACKAGE . ParallelResolver,Storage
+//go:generate mockgen -destination=mocks.go -package $GOPACKAGE . ParallelResolver,Storage,Unzipper

internal/provider/common/updater.go

@@ -20,7 +20,8 @@ type ParallelResolver interface {
 }
 
 type Unzipper interface {
-	FetchAndExtract(ctx context.Context, url string) (contents map[string][]byte, err error)
+	FetchAndExtract(ctx context.Context, url string) (
+		contents map[string][]byte, err error)
 }
 
 type Warner interface {

internal/provider/custom/connection.go

@@ -8,7 +8,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 	"github.com/qdm12/gluetun/internal/constants/vpn"
 	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/gluetun/internal/openvpn/extract"
 )
 
 var (
@@ -28,7 +27,7 @@ func (p *Provider) GetConnection(selection settings.ServerSelection) (
 	}
 }
 
-func getOpenVPNConnection(extractor extract.Interface,
+func getOpenVPNConnection(extractor extractor,
 	selection settings.ServerSelection) (
 	connection models.Connection, err error) {
 	_, connection, err = extractor.Data(*selection.OpenVPN.ConfFile)

internal/provider/custom/interfaces.go

@@ -0,0 +1,8 @@
+package custom
+
+import "github.com/qdm12/gluetun/internal/models"
+
+type extractor interface {
+	Data(filepath string) (lines []string,
+		connection models.Connection, err error)
+}

internal/provider/custom/provider.go

@@ -8,7 +8,7 @@ import (
 )
 
 type Provider struct {
-	extractor extract.Interface
+	extractor extractor
 	utils.NoPortForwarder
 	common.Fetcher
 }

internal/provider/expressvpn/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/fastestvpn/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/hidemyass/updater/updater.go

@@ -9,14 +9,10 @@ import (
 type Updater struct {
 	client    *http.Client
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, warner Warner) *Updater {
+func New(client *http.Client, warner common.Warner) *Updater {
 	return &Updater{
 		client:    client,
 		presolver: newParallelResolver(),

internal/provider/ipvanish/updater/servers_test.go

@@ -10,7 +10,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants/vpn"
 	"github.com/qdm12/gluetun/internal/models"
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip/mock_unzip"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -22,7 +21,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		minServers int
 
 		// Mocks
-		warnerBuilder func(ctrl *gomock.Controller) Warner
+		warnerBuilder func(ctrl *gomock.Controller) common.Warner
 
 		// Unzip
 		unzipContents map[string][]byte
@@ -40,25 +39,25 @@ func Test_Updater_GetServers(t *testing.T) {
 		err     error
 	}{
 		"unzipper error": {
-			warnerBuilder: func(ctrl *gomock.Controller) Warner { return nil },
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner { return nil },
 			unzipErr:      errors.New("dummy"),
 			err:           errors.New("dummy"),
 		},
 		"not enough unzip contents": {
 			minServers:    1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner { return nil },
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner { return nil },
 			unzipContents: map[string][]byte{},
 			err:           errors.New("not enough servers found: 0 and expected at least 1"),
 		},
 		"no openvpn file": {
 			minServers:    1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner { return nil },
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner { return nil },
 			unzipContents: map[string][]byte{"somefile.txt": {}},
 			err:           errors.New("not enough servers found: 0 and expected at least 1"),
 		},
 		"invalid proto": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("unknown protocol: invalid in badproto.ovpn")
 				return warner
@@ -68,7 +67,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"no host": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("remote host not found in nohost.ovpn")
 				return warner
@@ -78,7 +77,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"multiple hosts": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("only using the first host \"hosta\" and discarding 1 other hosts")
 				return warner
@@ -91,7 +90,7 @@ func Test_Updater_GetServers(t *testing.T) {
 			err:            errors.New("not enough servers found: 0 and expected at least 1"),
 		},
 		"resolve error": {
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("resolve warning")
 				return warner
@@ -107,7 +106,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"filename parsing error": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("country code is unknown: unknown in ipvanish-unknown-City-A-hosta.ovpn")
 				return warner
@@ -119,7 +118,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"success": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("resolve warning")
 				return warner
@@ -163,7 +162,7 @@ func Test_Updater_GetServers(t *testing.T) {
 
 			ctx := context.Background()
 
-			unzipper := mock_unzip.NewMockUnzipper(ctrl)
+			unzipper := common.NewMockUnzipper(ctrl)
 			const zipURL = "https://www.ipvanish.com/software/configs/configs.zip"
 			unzipper.EXPECT().FetchAndExtract(ctx, zipURL).
 				Return(testCase.unzipContents, testCase.unzipErr)

internal/provider/ipvanish/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
-	warner    Warner
+	unzipper  common.Unzipper
+	warner    common.Warner
 	presolver common.ParallelResolver
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		warner:    warner,

internal/provider/ivpn/updater/servers_test.go

@@ -25,7 +25,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		minServers int
 
 		// Mocks
-		warnerBuilder func(ctrl *gomock.Controller) Warner
+		warnerBuilder func(ctrl *gomock.Controller) common.Warner
 
 		// From API
 		responseBody   string
@@ -43,12 +43,12 @@ func Test_Updater_GetServers(t *testing.T) {
 		err     error
 	}{
 		"http response error": {
-			warnerBuilder:  func(ctrl *gomock.Controller) Warner { return nil },
+			warnerBuilder:  func(ctrl *gomock.Controller) common.Warner { return nil },
 			responseStatus: http.StatusNoContent,
 			err:            errors.New("failed fetching API: HTTP status code not OK: 204 No Content"),
 		},
 		"resolve error": {
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("resolve warning")
 				return warner
@@ -65,7 +65,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"not enough servers": {
 			minServers:    2,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner { return nil },
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner { return nil },
 			responseBody: `{"servers":[
 				{"hostnames":{"openvpn":"hosta"}}
 			]}`,
@@ -74,7 +74,7 @@ func Test_Updater_GetServers(t *testing.T) {
 		},
 		"success": {
 			minServers: 1,
-			warnerBuilder: func(ctrl *gomock.Controller) Warner {
+			warnerBuilder: func(ctrl *gomock.Controller) common.Warner {
 				warner := NewMockWarner(ctrl)
 				warner.EXPECT().Warn("resolve warning")
 				return warner

internal/provider/ivpn/updater/updater.go

@@ -9,14 +9,10 @@ import (
 type Updater struct {
 	client    *http.Client
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, warner Warner) *Updater {
+func New(client *http.Client, warner common.Warner) *Updater {
 	return &Updater{
 		client:    client,
 		presolver: newParallelResolver(),

internal/provider/nordvpn/updater/updater.go

@@ -2,18 +2,16 @@ package updater
 
 import (
 	"net/http"
+
+	"github.com/qdm12/gluetun/internal/provider/common"
 )
 
 type Updater struct {
 	client *http.Client
-	warner Warner
+	warner common.Warner
 }
 
-type Warner interface {
-	Warn(message string)
-}
-
-func New(client *http.Client, warner Warner) *Updater {
+func New(client *http.Client, warner common.Warner) *Updater {
 	return &Updater{
 		client: client,
 		warner: warner,

internal/provider/perfectprivacy/updater/updater.go

@@ -1,17 +1,15 @@
 package updater
 
-import "github.com/qdm12/gluetun/internal/updater/unzip"
+import (
+	"github.com/qdm12/gluetun/internal/provider/common"
+)
 
 type Updater struct {
-	unzipper unzip.Unzipper
-	warner   Warner
+	unzipper common.Unzipper
+	warner   common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper: unzipper,
 		warner:   warner,

internal/provider/privado/updater/updater.go

@@ -4,22 +4,17 @@ import (
 	"net/http"
 
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
 	client    *http.Client
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, unzipper unzip.Unzipper,
-	warner Warner) *Updater {
+func New(client *http.Client, unzipper common.Unzipper,
+	warner common.Warner) *Updater {
 	return &Updater{
 		client:    client,
 		unzipper:  unzipper,

internal/provider/privateinternetaccess/updater/updater.go

@@ -8,10 +8,6 @@ type Updater struct {
 	client *http.Client
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
 func New(client *http.Client) *Updater {
 	return &Updater{
 		client: client,

internal/provider/privatevpn/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/protonvpn/updater/updater.go

@@ -2,18 +2,16 @@ package updater
 
 import (
 	"net/http"
+
+	"github.com/qdm12/gluetun/internal/provider/common"
 )
 
 type Updater struct {
 	client *http.Client
-	warner Warner
+	warner common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, warner Warner) *Updater {
+func New(client *http.Client, warner common.Warner) *Updater {
 	return &Updater{
 		client: client,
 		warner: warner,

internal/provider/providers.go

@@ -82,7 +82,7 @@ func NewProviders(storage Storage, timeNow func() time.Time,
 	}
 }
 
-func (p *Providers) Get(providerName string) (provider Provider) {
+func (p *Providers) Get(providerName string) (provider Provider) { //nolint:ireturn
 	provider, ok := p.providerNameToProvider[providerName]
 	if !ok {
 		panic(fmt.Sprintf("provider %q not found", providerName))

internal/provider/purevpn/updater/updater.go

@@ -4,22 +4,17 @@ import (
 	"net/http"
 
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
 	client    *http.Client
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, unzipper unzip.Unzipper,
-	warner Warner) *Updater {
+func New(client *http.Client, unzipper common.Unzipper,
+	warner common.Warner) *Updater {
 	return &Updater{
 		client:    client,
 		unzipper:  unzipper,

internal/provider/surfshark/updater/updater.go

@@ -4,22 +4,17 @@ import (
 	"net/http"
 
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
 	client    *http.Client
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, unzipper unzip.Unzipper,
-	warner Warner) *Updater {
+func New(client *http.Client, unzipper common.Unzipper,
+	warner common.Warner) *Updater {
 	return &Updater{
 		client:    client,
 		unzipper:  unzipper,

internal/provider/surfshark/updater/zip.go

@@ -4,13 +4,13 @@ import (
 	"context"
 	"strings"
 
+	"github.com/qdm12/gluetun/internal/provider/common"
 	"github.com/qdm12/gluetun/internal/provider/surfshark/servers"
 	"github.com/qdm12/gluetun/internal/updater/openvpn"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 func addOpenVPNServersFromZip(ctx context.Context,
-	unzipper unzip.Unzipper, hts hostToServer) (
+	unzipper common.Unzipper, hts hostToServer) (
 	warnings []string, err error) {
 	const url = "https://my.surfshark.com/vpn/api/v1/server/configurations"
 	contents, err := unzipper.FetchAndExtract(ctx, url)

internal/provider/torguard/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/vpnunlimited/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/vyprvpn/updater/updater.go

@@ -2,20 +2,15 @@ package updater
 
 import (
 	"github.com/qdm12/gluetun/internal/provider/common"
-	"github.com/qdm12/gluetun/internal/updater/unzip"
 )
 
 type Updater struct {
-	unzipper  unzip.Unzipper
+	unzipper  common.Unzipper
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(unzipper unzip.Unzipper, warner Warner) *Updater {
+func New(unzipper common.Unzipper, warner common.Warner) *Updater {
 	return &Updater{
 		unzipper:  unzipper,
 		presolver: newParallelResolver(),

internal/provider/wevpn/updater/updater.go

@@ -4,14 +4,10 @@ import "github.com/qdm12/gluetun/internal/provider/common"
 
 type Updater struct {
 	presolver common.ParallelResolver
-	warner    Warner
+	warner    common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(warner Warner) *Updater {
+func New(warner common.Warner) *Updater {
 	return &Updater{
 		presolver: newParallelResolver(),
 		warner:    warner,

internal/provider/windscribe/updater/updater.go

@@ -2,18 +2,16 @@ package updater
 
 import (
 	"net/http"
+
+	"github.com/qdm12/gluetun/internal/provider/common"
 )
 
 type Updater struct {
 	client *http.Client
-	warner Warner
+	warner common.Warner
 }
 
-type Warner interface {
-	Warn(s string)
-}
-
-func New(client *http.Client, warner Warner) *Updater {
+func New(client *http.Client, warner common.Warner) *Updater {
 	return &Updater{
 		client: client,
 		warner: warner,

internal/publicip/alias.go

@@ -1,6 +0,0 @@
-package publicip
-
-import "github.com/qdm12/gluetun/internal/publicip/state"
-
-type GetSetter = state.DataGetSetter
-type SettingsGetSetter = state.SettingsGetSetter

internal/publicip/fetch.go

@@ -12,12 +12,6 @@ import (
 	"strings"
 )
 
-var _ Fetcher = (*Fetch)(nil)
-
-type Fetcher interface {
-	FetchPublicIP(ctx context.Context) (ip net.IP, err error)
-}
-
 type Fetch struct {
 	client   *http.Client
 	randIntn func(n int) int

internal/publicip/interfaces.go

@@ -0,0 +1,28 @@
+package publicip
+
+import (
+	"context"
+	"net"
+
+	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+	publicipmodels "github.com/qdm12/gluetun/internal/publicip/models"
+)
+
+type statusManager interface {
+	GetStatus() (status models.LoopStatus)
+	SetStatus(status models.LoopStatus)
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}
+
+type stateManager interface {
+	GetData() (data publicipmodels.IPInfoData)
+	SetData(data publicipmodels.IPInfoData)
+	GetSettings() (settings settings.PublicIP)
+	SetSettings(ctx context.Context, settings settings.PublicIP) (outcome string)
+}
+
+type fetcher interface {
+	FetchPublicIP(ctx context.Context) (ip net.IP, err error)
+}

internal/publicip/loop.go

@@ -11,22 +11,11 @@ import (
 	"github.com/qdm12/gluetun/internal/publicip/state"
 )
 
-var _ Looper = (*Loop)(nil)
-
-type Looper interface {
-	Runner
-	RestartTickerRunner
-	loopstate.Getter
-	loopstate.Applier
-	SettingsGetSetter
-	GetSetter
-}
-
 type Loop struct {
-	statusManager loopstate.Manager
-	state         state.Manager
+	statusManager statusManager
+	state         stateManager
 	// Objects
-	fetcher Fetcher
+	fetcher fetcher
 	client  *http.Client
 	logger  Logger
 	// Fixed settings

internal/publicip/runner.go

@@ -8,10 +8,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type Runner interface {
-	Run(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) Run(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 

internal/publicip/state/publicip.go

@@ -4,11 +4,6 @@ import (
 	"github.com/qdm12/gluetun/internal/publicip/models"
 )
 
-type DataGetSetter interface {
-	GetData() (data models.IPInfoData)
-	SetData(data models.IPInfoData)
-}
-
 func (s *State) GetData() (data models.IPInfoData) {
 	s.ipDataMu.RLock()
 	defer s.ipDataMu.RUnlock()

internal/publicip/state/settings.go

@@ -7,12 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/configuration/settings"
 )
 
-type SettingsGetSetter interface {
-	GetSettings() (settings settings.PublicIP)
-	SetSettings(ctx context.Context,
-		settings settings.PublicIP) (outcome string)
-}
-
 func (s *State) GetSettings() (settings settings.PublicIP) {
 	s.settingsMu.RLock()
 	defer s.settingsMu.RUnlock()

internal/publicip/state/state.go

@@ -1,21 +1,15 @@
 package state
 
 import (
+	"context"
 	"sync"
 
 	"github.com/qdm12/gluetun/internal/configuration/settings"
-	"github.com/qdm12/gluetun/internal/loopstate"
-	"github.com/qdm12/gluetun/internal/publicip/models"
+	"github.com/qdm12/gluetun/internal/models"
+	publicipmodels "github.com/qdm12/gluetun/internal/publicip/models"
 )
 
-var _ Manager = (*State)(nil)
-
-type Manager interface {
-	SettingsGetSetter
-	DataGetSetter
-}
-
-func New(statusApplier loopstate.Applier,
+func New(statusApplier StatusApplier,
 	settings settings.PublicIP,
 	updateTicker chan<- struct{}) *State {
 	return &State{
@@ -26,13 +20,18 @@ func New(statusApplier loopstate.Applier,
 }
 
 type State struct {
-	statusApplier loopstate.Applier
+	statusApplier StatusApplier
 
 	settings   settings.PublicIP
 	settingsMu sync.RWMutex
 
-	ipData   models.IPInfoData
+	ipData   publicipmodels.IPInfoData
 	ipDataMu sync.RWMutex
 
 	updateTicker chan<- struct{}
 }
+
+type StatusApplier interface {
+	ApplyStatus(ctx context.Context, status models.LoopStatus) (
+		outcome string, err error)
+}

internal/publicip/ticker.go

@@ -7,10 +7,6 @@ import (
 	"github.com/qdm12/gluetun/internal/constants"
 )
 
-type RestartTickerRunner interface {
-	RunRestartTicker(ctx context.Context, done chan<- struct{})
-}
-
 func (l *Loop) RunRestartTicker(ctx context.Context, done chan<- struct{}) {
 	defer close(done)
 	timer := time.NewTimer(time.Hour)
@@ -30,7 +26,7 @@ func (l *Loop) RunRestartTicker(ctx context.Context, done chan<- struct{}) {
 			return
 		case <-timer.C:
 			lastTick = l.timeNow()
-			_, _ = l.ApplyStatus(ctx, constants.Running)
+			_, _ = l.statusManager.ApplyStatus(ctx, constants.Running)
 			timer.Reset(*l.state.GetSettings().Period)
 		case <-l.updateTicker:
 			if !timerIsStopped && !timer.Stop() {

internal/routing/default.go

@@ -12,10 +12,6 @@ var (
 	ErrRouteDefaultNotFound = errors.New("default route not found")
 )
 
-type DefaultRouteGetter interface {
-	DefaultRoutes() (defaultRoutes []DefaultRoute, err error)
-}
-
 type DefaultRoute struct {
 	NetInterface string
 	Gateway      net.IP

internal/routing/enable.go

@@ -4,10 +4,6 @@ import (
 	"fmt"
 )
 
-type Setuper interface {
-	Setup() (err error)
-}
-
 func (r *Routing) Setup() (err error) {
 	defaultRoutes, err := r.DefaultRoutes()
 	if err != nil {
@@ -40,10 +36,6 @@ func (r *Routing) Setup() (err error) {
 	return nil
 }
 
-type TearDowner interface {
-	TearDown() error
-}
-
 func (r *Routing) TearDown() error {
 	defaultRoutes, err := r.DefaultRoutes()
 	if err != nil {

internal/routing/local.go

@@ -20,10 +20,6 @@ type LocalNetwork struct {
 	IP            net.IP
 }
 
-type LocalNetworksGetter interface {
-	LocalNetworks() (localNetworks []LocalNetwork, err error)
-}
-
 func (r *Routing) LocalNetworks() (localNetworks []LocalNetwork, err error) {
 	links, err := r.netLinker.LinkList()
 	if err != nil {

internal/routing/mocks_generate_test.go

@@ -0,0 +1,3 @@
+package routing
+
+//go:generate mockgen -destination=mocks_test.go -package=$GOPACKAGE . NetLinker

internal/routing/mocks_test.go

@@ -1,8 +1,8 @@
 // Code generated by MockGen. DO NOT EDIT.
-// Source: github.com/qdm12/gluetun/internal/netlink (interfaces: NetLinker)
+// Source: github.com/qdm12/gluetun/internal/routing (interfaces: NetLinker)
 
-// Package mock_netlink is a generated GoMock package.
-package mock_netlink
+// Package routing is a generated GoMock package.
+package routing
 
 import (
 	reflect "reflect"

internal/routing/outbound.go

@@ -12,10 +12,6 @@ const (
 	outboundPriority = 99
 )
 
-type OutboundRoutesSetter interface {
-	SetOutboundRoutes(outboundSubnets []net.IPNet) error
-}
-
 func (r *Routing) SetOutboundRoutes(outboundSubnets []net.IPNet) error {
 	defaultRoutes, err := r.DefaultRoutes()
 	if err != nil {