Add initial prototype (#1)

* Add survey library to select server

* Add speedtest

* Add --random flag to connect

* Add list command

* Cache server list

* Tail the openvpn logs so that it appears in vpngate logs

* Add goreleaser action

* Add golangci-lint action

pkg/vpn/cache.go

@@ -0,0 +1,89 @@
+package vpn
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path"
+	"time"
+
+	"github.com/rs/zerolog/log"
+	"github.com/spf13/afero"
+)
+
+const serverCachefile = "servers.json"
+
+func getCacheDir() string {
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		log.Error().Msgf("Failed to get user's home directory: %s ", err)
+		return ""
+	}
+	cacheDir := path.Join(homeDir, ".vpngate", "cache")
+	return cacheDir
+}
+
+func createCacheDir() error {
+	cacheDir := getCacheDir()
+	var AppFs = afero.NewOsFs()
+	return AppFs.MkdirAll(cacheDir, 0700)
+}
+
+func getVpnListCache() (*[]Server, error) {
+	cacheFile := path.Join(getCacheDir(), serverCachefile)
+	serversFile, err := os.Open(cacheFile)
+
+	if err != nil {
+		return nil, err
+	}
+
+	byteValue, err := ioutil.ReadAll(serversFile)
+
+	if err != nil {
+		return nil, err
+	}
+
+	var servers []Server
+
+	err = json.Unmarshal(byteValue, &servers)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return &servers, nil
+}
+
+func writeVpnListToCache(servers []Server) error {
+
+	err := createCacheDir()
+
+	if err != nil {
+		return err
+	}
+
+	f, err := json.MarshalIndent(servers, "", " ")
+
+	if err != nil {
+		return err
+	}
+
+	cacheFile := path.Join(getCacheDir(), serverCachefile)
+
+	err = ioutil.WriteFile(cacheFile, f, 0644)
+
+	return err
+
+}
+
+func vpnListCacheIsExpired() bool {
+	file, err := os.Stat(path.Join(getCacheDir(), serverCachefile))
+
+	if err != nil {
+		return true
+	}
+
+	lastModified := file.ModTime()
+
+	return (time.Since(lastModified)) > time.Duration(24*time.Hour)
+}

pkg/vpn/client.go

@@ -0,0 +1,48 @@
+package vpn
+
+import (
+	"io/ioutil"
+	"os"
+	"time"
+
+	"github.com/davegallant/vpngate/pkg/exec"
+	"github.com/davegallant/vpngate/pkg/network"
+	"github.com/hpcloud/tail"
+	"github.com/juju/errors"
+	"github.com/rs/zerolog/log"
+)
+
+// Connect to a specified OpenVPN configuration
+func Connect(configPath string) error {
+
+	tmpLogFile, err := ioutil.TempFile("", "vpngate-openvpn-log-")
+	if err != nil {
+		return errors.Annotate(err, "Unable to create a temporary log file")
+	}
+	defer os.Remove(tmpLogFile.Name())
+
+	go func() {
+		for {
+			err = network.TestSpeed()
+			if err != nil {
+				log.Error().Msg("Failed to test network speed")
+			}
+			time.Sleep(time.Minute)
+		}
+
+	}()
+
+	go func() {
+		// Tail the temporary openvpn log file
+		t, err := tail.TailFile(tmpLogFile.Name(), tail.Config{Follow: true})
+		if err != nil {
+			log.Error().Msgf("%s", err)
+		}
+		for line := range t.Lines {
+			log.Debug().Msg(line.Text)
+		}
+	}()
+
+	_, err = exec.Run("openvpn", ".", "--verb", "4", "--log", tmpLogFile.Name(), "--config", configPath)
+	return err
+}

pkg/vpn/list.go

@@ -0,0 +1,104 @@
+package vpn
+
+import (
+	"net/http"
+
+	"bytes"
+	"io"
+
+	"github.com/jszwec/csvutil"
+	"github.com/rs/zerolog/log"
+
+	"github.com/juju/errors"
+)
+
+const (
+	vpnList = "https://www.vpngate.net/api/iphone/"
+)
+
+// Server holds in formation about a vpn relay server
+type Server struct {
+	HostName          string `csv:"#HostName"`
+	CountryLong       string `csv:"CountryLong"`
+	CountryShort      string `csv:"CountryShort"`
+	Score             int    `csv:"Score"`
+	IPAddr            string `csv:"IP"`
+	OpenVpnConfigData string `csv:"OpenVPN_ConfigData_Base64"`
+	Ping              string `csv:"Ping"`
+}
+
+func streamToBytes(stream io.Reader) []byte {
+	buf := new(bytes.Buffer)
+	_, err := buf.ReadFrom(stream)
+	if err != nil {
+		log.Error().Msg("Unable to stream bytes")
+	}
+	return buf.Bytes()
+}
+
+// parse csv
+func parseVpnList(r io.Reader) (*[]Server, error) {
+
+	var servers []Server
+
+	serverList := streamToBytes(r)
+
+	// Trim known invalid rows
+	serverList = bytes.TrimPrefix(serverList, []byte("*vpn_servers\r\n"))
+	serverList = bytes.TrimSuffix(serverList, []byte("*\r\n"))
+
+	if err := csvutil.Unmarshal(serverList, &servers); err != nil {
+		return nil, errors.Annotatef(err, "Unable to parse CSV")
+	}
+
+	return &servers, nil
+
+}
+
+// GetList returns a list of vpn servers
+func GetList() (*[]Server, error) {
+
+	cacheExpired := vpnListCacheIsExpired()
+
+	var servers *[]Server
+
+	if !cacheExpired {
+		servers, err := getVpnListCache()
+
+		if err != nil {
+			log.Info().Msg("Unable to retrieve vpn list from cache")
+		} else {
+			return servers, nil
+		}
+
+	} else {
+		log.Info().Msg("The vpn server list cache has expired")
+	}
+
+	log.Info().Msg("Fetching the latest server list")
+	r, err := http.Get(vpnList)
+
+	if err != nil {
+		return nil, errors.Annotate(err, "Unable to retrieve vpn list")
+	}
+
+	defer r.Body.Close()
+
+	if r.StatusCode != 200 {
+		return nil, errors.Annotatef(err, "Unexpected status code when retrieving vpn list: %d", r.StatusCode)
+	}
+
+	servers, err = parseVpnList(r.Body)
+
+	if err != nil {
+		return nil, errors.Annotate(err, "unable to parse vpn list")
+	}
+
+	err = writeVpnListToCache(*servers)
+
+	if err != nil {
+		log.Warn().Msgf("Unable to write servers to cache: %s", err)
+	}
+
+	return servers, nil
+}