Code maintenance: OS package for file system

- OS custom internal package for file system interaction
- Remove fileManager external dependency
- Closer API to Go's native API on the OS
- Create directories at startup
- Better testability
- Move Unsetenv to os interface

internal/params/cyberghost.go

@@ -3,6 +3,8 @@ package params
 import (
 	"encoding/pem"
 	"fmt"
+	"io/ioutil"
+	"os"
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/constants"
@@ -32,10 +34,19 @@ func (p *reader) GetCyberghostClientKey() (clientKey string, err error) {
 	} else if len(clientKey) > 0 {
 		return clientKey, nil
 	}
-	content, err := p.fileManager.ReadFile(string(constants.ClientKey))
+	const filepath = string(constants.ClientKey)
+	file, err := p.os.OpenFile(filepath, os.O_RDONLY, 0)
 	if err != nil {
 		return "", err
 	}
+	content, err := ioutil.ReadAll(file)
+	if err != nil {
+		_ = file.Close()
+		return "", err
+	}
+	if err := file.Close(); err != nil {
+		return "", err
+	}
 	return extractClientKey(content)
 }
 
@@ -55,10 +66,19 @@ func extractClientKey(b []byte) (key string, err error) {
 // GetCyberghostClientCertificate obtains the client certificate to use for openvpn from the
 // file at /gluetun/client.crt.
 func (p *reader) GetCyberghostClientCertificate() (clientCertificate string, err error) {
-	content, err := p.fileManager.ReadFile(string(constants.ClientCertificate))
+	const filepath = string(constants.ClientCertificate)
+	file, err := p.os.OpenFile(filepath, os.O_RDONLY, 0)
 	if err != nil {
 		return "", err
 	}
+	content, err := ioutil.ReadAll(file)
+	if err != nil {
+		_ = file.Close()
+		return "", err
+	}
+	if err := file.Close(); err != nil {
+		return "", err
+	}
 	return extractClientCertificate(content)
 }
 

internal/params/openvpn.go

@@ -11,7 +11,7 @@ import (
 // GetUser obtains the user to use to connect to the VPN servers.
 func (r *reader) GetUser() (s string, err error) {
 	defer func() {
-		unsetenvErr := r.unsetEnv("USER")
+		unsetenvErr := r.os.Unsetenv("USER")
 		if err == nil {
 			err = unsetenvErr
 		}
@@ -22,7 +22,7 @@ func (r *reader) GetUser() (s string, err error) {
 // GetPassword obtains the password to use to connect to the VPN servers.
 func (r *reader) GetPassword(required bool) (s string, err error) {
 	defer func() {
-		unsetenvErr := r.unsetEnv("PASSWORD")
+		unsetenvErr := r.os.Unsetenv("PASSWORD")
 		if err == nil {
 			err = unsetenvErr
 		}

internal/params/params.go

@@ -2,11 +2,10 @@ package params
 
 import (
 	"net"
-	"os"
 	"time"
 
 	"github.com/qdm12/gluetun/internal/models"
-	"github.com/qdm12/golibs/files"
+	"github.com/qdm12/gluetun/internal/os"
 	"github.com/qdm12/golibs/logging"
 	libparams "github.com/qdm12/golibs/params"
 	"github.com/qdm12/golibs/verification"
@@ -128,22 +127,20 @@ type Reader interface {
 }
 
 type reader struct {
-	envParams   libparams.EnvParams
-	logger      logging.Logger
-	verifier    verification.Verifier
-	unsetEnv    func(key string) error
-	fileManager files.FileManager
+	envParams libparams.EnvParams
+	logger    logging.Logger
+	verifier  verification.Verifier
+	os        os.OS
 }
 
 // Newreader returns a paramsReadeer object to read parameters from
 // environment variables.
-func NewReader(logger logging.Logger, fileManager files.FileManager) Reader {
+func NewReader(logger logging.Logger, os os.OS) Reader {
 	return &reader{
-		envParams:   libparams.NewEnvParams(),
-		logger:      logger,
-		verifier:    verification.NewVerifier(),
-		unsetEnv:    os.Unsetenv,
-		fileManager: fileManager,
+		envParams: libparams.NewEnvParams(),
+		logger:    logger,
+		verifier:  verification.NewVerifier(),
+		os:        os,
 	}
 }
 

internal/params/shadowsocks.go

@@ -36,7 +36,7 @@ func (r *reader) GetShadowSocksPort() (port uint16, err error) {
 // SHADOWSOCKS_PASSWORD.
 func (r *reader) GetShadowSocksPassword() (password string, err error) {
 	defer func() {
-		unsetErr := r.unsetEnv("SHADOWSOCKS_PASSWORD")
+		unsetErr := r.os.Unsetenv("SHADOWSOCKS_PASSWORD")
 		if err == nil {
 			err = unsetErr
 		}