add loading

command.go

@@ -1,13 +1,9 @@
 package main
 
-import (
-	"os"
-	"os/exec"
-)
+import "os/exec"
 
 func getCmdOutput(cmds ...string) ([]byte, error) {
 	command := exec.Command(cmds[0], cmds[1:]...)
-	command.Stderr = os.Stderr
 	output, err := command.Output()
 	if err != nil {
 		return nil, err

go.mod

@@ -5,6 +5,11 @@ go 1.18
 require github.com/olekukonko/tablewriter v0.0.5
 
 require (
+	github.com/briandowns/spinner v1.18.1 // indirect
+	github.com/fatih/color v1.7.0 // indirect
+	github.com/mattn/go-colorable v0.1.2 // indirect
+	github.com/mattn/go-isatty v0.0.8 // indirect
 	github.com/mattn/go-runewidth v0.0.13 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect
+	golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223 // indirect
 )

go.sum

@@ -1,7 +1,17 @@
+github.com/briandowns/spinner v1.18.1 h1:yhQmQtM1zsqFsouh09Bk/jCjd50pC3EOGsh28gLVvwY=
+github.com/briandowns/spinner v1.18.1/go.mod h1:mQak9GHqbspjC/5iUx3qMlIho8xBS/ppAL/hX5SmPJU=
+github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
+github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
+github.com/mattn/go-colorable v0.1.2 h1:/bC9yWikZXAL9uJdulbSfyVNIR3n3trXl+v8+1sx8mU=
+github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
+github.com/mattn/go-isatty v0.0.8 h1:HLtExJ+uU2HOZ+wI0Tt5DtUDrx8yhUqDcp7fYERX4CE=
+github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
 github.com/mattn/go-runewidth v0.0.13 h1:lTGmDsbAYt5DmK6OnoV7EuIF1wEIFAcxld6ypU4OSgU=
 github.com/mattn/go-runewidth v0.0.13/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
 github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/rivo/uniseg v0.2.0 h1:S1pD9weZBuJdFmowNwbpi7BJ8TNftyUImj/0WQi72jY=
 github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223 h1:DH4skfRX4EBpamg7iV4ZlCpblAHI6s6TDM39bFZumv8=
+golang.org/x/sys v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

main.go

@@ -1,25 +1,35 @@
 package main
 
 import (
-	"fmt"
 	"os"
+	"os/exec"
+	"time"
 
+	"github.com/briandowns/spinner"
+	"github.com/fatih/color"
 	"github.com/olekukonko/tablewriter"
 )
 
 func main() {
+	spin := spinner.New(spinner.CharSets[14], 100*time.Millisecond)
+	spin.Suffix = " Checking for updates..."
+	spin.Start()
+
 	directs, err := getDirectModules()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "parseGoMod: %v\n", err)
+		spin.Stop()
+		processError("parseGoMod", err)
 		return
 	}
 
 	modules, err := getDepPackages()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "parseModules: %v\n", err)
+		spin.Stop()
+		processError("parseModules", err)
 		return
 	}
 
+	spin.Stop()
 	table := tablewriter.NewWriter(os.Stdout)
 	table.SetHeader([]string{"Package", "Current", "Latest", "GoVersion"})
 	table.SetBorder(false)
@@ -52,3 +62,13 @@ func contains(list []string, str string) bool {
 
 	return false
 }
+
+func processError(action string, err error) {
+	writer := color.New(color.FgRed)
+	if e, ok := err.(*exec.ExitError); ok {
+		writer.Fprintf(os.Stderr, "%s: %s", action, string(e.Stderr))
+		os.Exit(e.ExitCode())
+	} else {
+		writer.Fprintf(os.Stderr, "%s: %s\n", action, err.Error())
+	}
+}