Added version checking.

main.go

@@ -13,6 +13,9 @@ var CurrentCLIVersion string
 
 func Execute() {
 	CurrentCLIVersion = version
+
+	MaybeCheckVersion()
+
 	if err := rootCmd.Execute(); err != nil {
 		fmt.Println(err)
 		os.Exit(0)

versionCheck.go

@@ -0,0 +1,90 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	goVersion "github.com/hashicorp/go-version"
+	"github.com/logrusorgru/aurora"
+	"io/ioutil"
+	"math/rand"
+	"net/http"
+	"sort"
+)
+
+type commit struct {
+	Sha string `json:"sha"`
+	Url string `json:"url"`
+}
+
+type tagResults struct {
+	Name       string `json:"name"`
+	ZipballUrl string `json:"zipball_url"`
+	TarballUrl string `json:"tarball_url"`
+	Commit     commit `json:"commit"`
+	NodeId     string `json:"node_id"`
+}
+
+func MaybeCheckVersion() {
+	randInt := rand.Intn(25)
+
+	if randInt != 24 {
+		return
+	}
+
+	response, err := http.Get("https://api.github.com/repos/tenderly/tenderly-cli/tags")
+
+	if err != nil {
+		return
+	}
+
+	defer response.Body.Close()
+
+	contents, err := ioutil.ReadAll(response.Body)
+	if err != nil {
+		return
+	}
+
+	var result []tagResults
+	err = json.Unmarshal(contents, &result)
+
+	if err != nil {
+		return
+	}
+
+	if len(result) == 0 {
+		return
+	}
+
+	sort.Slice(result, func(i, j int) bool {
+		v1, err := goVersion.NewVersion(result[i].Name)
+		if err != nil {
+			return true
+		}
+
+		v2, err := goVersion.NewVersion(result[j].Name)
+
+		return v1.GreaterThan(v2)
+	})
+
+	currentVersion, err := goVersion.NewVersion(CurrentCLIVersion)
+	if err != nil {
+		return
+	}
+
+	newestVersion, err := goVersion.NewVersion(result[0].Name)
+	if err != nil {
+		return
+	}
+
+	if !newestVersion.GreaterThan(currentVersion) {
+		return
+	}
+
+	fmt.Println(
+		aurora.Sprintf("\nYou are running version %s of the Tenderly CLI. To update to the newest version (%s) please run the following command:\n\n%s\n\n",
+			aurora.Bold(aurora.Green(CurrentCLIVersion)),
+			aurora.Bold(aurora.Green(result[0].Name)),
+			aurora.Bold(aurora.Green("brew update && brew upgrade tenderly")),
+		),
+	)
+}