feat: add colors for logs

Author: danya

internal/app/enaptercli/cmd_base.go

@@ -31,9 +31,10 @@ type cmdBase struct {
 	siteID           string
 	apiAllowInsecure bool
 	verbose          bool
-	userAgent        string
+	colorize         bool
 	writer           io.Writer
 	errWriter        io.Writer
+	userAgent        string
 	httpClient       *http.Client
 }
 
@@ -83,9 +84,11 @@ func (c *cmdBase) Before(cliCtx *cli.Context) error {
 		return err
 	}
 
-	c.userAgent = "enapter-cli/" + cliCtx.App.Version
 	c.writer = cliCtx.App.Writer
 	c.errWriter = cliCtx.App.ErrWriter
+	c.colorize = colorsSupported(c.writer)
+
+	c.userAgent = "enapter-cli/" + cliCtx.App.Version
 	c.httpClient = &http.Client{
 		Transport: &http.Transport{
 			//nolint:gosec // This is needed to allow self-signed certificates on Gateway.

internal/app/enaptercli/cmd_device_logs.go

@@ -148,7 +148,15 @@ func (c *cmdDeviceLogs) doFollow(ctx context.Context) error {
 			if err := json.NewDecoder(r).Decode(&msg); err != nil {
 				return fmt.Errorf("parse payload: %w", err)
 			}
+
+			color := c.logColor(msg.Log.Severity)
+			if color != "" {
+				fmt.Fprint(c.writer, color)
+			}
 			fmt.Fprintf(c.writer, "%s [%s] %s\n", msg.ReceivedAt, msg.Log.Severity, msg.Log.Message)
+			if color != "" {
+				fmt.Fprint(c.writer, colorReset)
+			}
 			return nil
 		},
 	})
@@ -196,9 +204,30 @@ func (c *cmdDeviceLogs) doList(ctx context.Context) error {
 				return fmt.Errorf("parse response body: %w", err)
 			}
 			for _, l := range resp.Logs {
+				color := c.logColor(l.Severity)
+				if color != "" {
+					fmt.Fprint(c.writer, color)
+				}
 				fmt.Fprintf(c.writer, "%s [%s] %s\n", l.ReceivedAt, l.Severity, l.Message)
+				if color != "" {
+					fmt.Fprint(c.writer, colorReset)
+				}
 			}
 			return nil
 		}),
 	})
 }
+
+func (c *cmdDeviceLogs) logColor(severity string) string {
+	if !c.colorize {
+		return ""
+	}
+	switch severity {
+	case "warning":
+		return colorYellow
+	case "error":
+		return colorRed
+	default:
+		return ""
+	}
+}

internal/app/enaptercli/cmd_device_monitor.go

@@ -132,6 +132,11 @@ func (c *cmdDeviceMonitor) process(r io.Reader, deviceID, runtimeID string) erro
 		return fmt.Errorf("parse payload: %w", err)
 	}
 
+	color := c.messageColor(m)
+	if color != "" {
+		fmt.Fprint(c.writer, color)
+	}
+
 	fmt.Fprint(c.writer, c.messageTimestamp(m))
 	fmt.Fprint(c.writer, " ")
 
@@ -154,11 +159,29 @@ func (c *cmdDeviceMonitor) process(r io.Reader, deviceID, runtimeID string) erro
 		fmt.Fprintf(c.writer, "[%s] %s", m.Log.Severity, m.Log.Message)
 	}
 
+	if color != "" {
+		fmt.Fprint(c.writer, colorReset)
+	}
 	fmt.Fprintln(c.writer)
 
 	return nil
 }
 
+func (c *cmdDeviceMonitor) messageColor(m streamMessage) string {
+	if !c.colorize {
+		return ""
+	}
+	if m.Log != nil {
+		switch m.Log.Severity {
+		case "warning":
+			return colorYellow
+		case "error":
+			return colorRed
+		}
+	}
+	return ""
+}
+
 func (c *cmdDeviceMonitor) messageTimestamp(m streamMessage) string {
 	ts := m.ReceivedAt
 	if ts.IsZero() {

internal/app/enaptercli/colors.go

@@ -0,0 +1,28 @@
+package enaptercli
+
+import (
+	"io"
+	"os"
+
+	"golang.org/x/term"
+)
+
+const (
+	colorRed    = "\033[31m"
+	colorYellow = "\033[33m"
+	colorReset  = "\033[0m"
+)
+
+func colorsSupported(w io.Writer) bool {
+	f, ok := w.(*os.File)
+	if !ok {
+		return false
+	}
+	if !term.IsTerminal(int(f.Fd())) {
+		return false
+	}
+	if _, ok := os.LookupEnv("NO_COLOR"); ok {
+		return false
+	}
+	return true
+}