fix pktvisor-cli version warning (#220)

Co-authored-by: leoparente <[email protected]>

Author: weyrick

Diff for: golang/go.mod

@@ -3,6 +3,7 @@ module pktvisor
 go 1.15
 
 require (
+	github.com/hashicorp/go-version v1.3.0
 	github.com/jroimartin/gocui v0.5.0
 	github.com/mitchellh/mapstructure v1.4.2
 	github.com/pkg/errors v0.9.1

Diff for: golang/go.sum

@@ -1,3 +1,5 @@
+github.com/hashicorp/go-version v1.3.0 h1:McDWVJIU/y+u1BRV06dPaLfLCaT7fUTJLp5r04x7iNw=
+github.com/hashicorp/go-version v1.3.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
 github.com/jroimartin/gocui v0.5.0 h1:DCZc97zY9dMnHXJSJLLmx9VqiEnAj0yh0eTNpuEtG/4=
 github.com/jroimartin/gocui v0.5.0/go.mod h1:l7Hz8DoYoL6NoYnlnaX6XCNR62G7J5FfSW5jEogzaxE=
 github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=

Diff for: golang/pkg/client/client.go

@@ -7,6 +7,7 @@ package client
 import (
 	"encoding/json"
 	"fmt"
+	"github.com/hashicorp/go-version"
 	"github.com/mitchellh/mapstructure"
 	"github.com/pkg/errors"
 	"io/ioutil"
@@ -16,10 +17,6 @@ import (
 	"time"
 )
 
-const (
-	wantServerVersion = "3.3"
-)
-
 type Client interface {
 	GetStats() (*StatSnapshot, error)
 	GetServerVersion() string
@@ -55,8 +52,17 @@ func (c *client) GetServerVersion() string {
 		return "unknown"
 	}
 	c.serverVersion = appMetrics.App.Version
-	if c.serverVersion[0:3] != wantServerVersion {
-		log.Println(fmt.Sprintf("WARNING: this version of pktvisor-cli was written for pktvisord %s.x", wantServerVersion))
+	serverVersion, err := version.NewVersion(c.serverVersion)
+	if err == nil {
+		clientVersion, err := version.NewVersion(VisorVersionNum)
+		if err == nil {
+			cMajor := clientVersion.Segments()[0]
+			sMajor := serverVersion.Segments()[0]
+			if sMajor != cMajor {
+				log.Println(fmt.Sprintf("WARNING: this version of pktvisor-cli was written for a different major pktvisord version (server:%d, client:%d)", cMajor, sMajor))
+				time.Sleep(3 * time.Second)
+			}
+		}
 	}
 	return c.serverVersion
 }