Add format flag to listen cmd (stripe#615)

pkg/cmd/listen.go

@@ -33,6 +33,7 @@ type listenCmd struct {
 	livemode              bool
 	useConfiguredWebhooks bool
 	printJSON             bool
+	format                string
 	skipVerify            bool
 	onlyPrintSecret       bool
 	skipUpdate            bool
@@ -64,7 +65,11 @@ Stripe account.`,
 	lc.cmd.Flags().StringVarP(&lc.forwardConnectURL, "forward-connect-to", "c", "", "The URL to forward Connect webhook events to (default: same as normal events)")
 	lc.cmd.Flags().BoolVarP(&lc.latestAPIVersion, "latest", "l", false, "Receive events formatted with the latest API version (default: your account's default API version)")
 	lc.cmd.Flags().BoolVar(&lc.livemode, "live", false, "Receive live events (default: test)")
-	lc.cmd.Flags().BoolVarP(&lc.printJSON, "print-json", "j", false, "Print full JSON objects to stdout")
+	lc.cmd.Flags().BoolVarP(&lc.printJSON, "print-json", "j", false, "Print full JSON objects to stdout.")
+	lc.cmd.Flags().MarkDeprecated("print-json", "Please use `--format JSON` instead and use `jq` if you need to process the JSON in the terminal.")
+	lc.cmd.Flags().StringVar(&lc.format, "format", "", `Specifies the output format of webhook events
+	Acceptable values:
+		'JSON' - Output webhook events in JSON format`)
 	lc.cmd.Flags().BoolVarP(&lc.useConfiguredWebhooks, "use-configured-webhooks", "a", false, "Load webhook endpoint configuration from the webhooks API/dashboard")
 	lc.cmd.Flags().BoolVarP(&lc.skipVerify, "skip-verify", "", false, "Skip certificate verification when forwarding to HTTPS endpoints")
 	lc.cmd.Flags().BoolVar(&lc.onlyPrintSecret, "print-secret", false, "Only print the webhook signing secret and exit")
@@ -170,6 +175,7 @@ func (lc *listenCmd) runListenCmd(cmd *cobra.Command, args []string) error {
 		APIBaseURL:          lc.apiBaseURL,
 		WebSocketFeature:    webhooksWebSocketFeature,
 		PrintJSON:           lc.printJSON,
+		Format:              lc.format,
 		UseLatestAPIVersion: lc.latestAPIVersion,
 		SkipVerify:          lc.skipVerify,
 		Log:                 log.StandardLogger(),

pkg/logtailing/tailer.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"os/signal"
 	"reflect"
+	"strings"
 	"syscall"
 	"time"
 
@@ -257,7 +258,7 @@ func (t *Tailer) processRequestLogEvent(msg websocket.IncomingMessage) {
 		return
 	}
 
-	if t.cfg.OutputFormat == outputFormatJSON {
+	if strings.ToUpper(t.cfg.OutputFormat) == outputFormatJSON {
 		fmt.Println(ansi.ColorizeJSON(requestLogEvent.EventPayload, false, os.Stdout))
 		return
 	}

pkg/proxy/proxy.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"os"
 	"os/signal"
+	"strings"
 	"syscall"
 	"time"
 
@@ -59,6 +60,9 @@ type Config struct {
 	// Indicates whether to print full JSON objects to stdout
 	PrintJSON bool
 
+	// Specifies the format to print to stdout.
+	Format string
+
 	// Indicates whether to filter events formatted with the default or latest API version
 	UseLatestAPIVersion bool
 
@@ -230,6 +234,25 @@ func (p *Proxy) filterWebhookEvent(msg *websocket.WebhookEvent) bool {
 	return false
 }
 
+// This function outputs the event payload in the format specified.
+// Currently only supports JSON.
+func (p *Proxy) formatOutput(format string, eventPayload string) {
+	var event map[string]interface{}
+	err := json.Unmarshal([]byte(eventPayload), &event)
+	if err != nil {
+		p.cfg.Log.Debug("Received malformed event from Stripe, ignoring")
+		return
+	}
+	switch strings.ToUpper(format) {
+	// The distinction between this and PrintJSON is that this output is stripped of all pretty format.
+	case outputFormatJSON:
+		outputJSON, _ := json.Marshal(event)
+		fmt.Println(ansi.ColorizeJSON(string(outputJSON), false, os.Stdout))
+	default:
+		fmt.Printf("Unrecognized output format %s\n" + format)
+	}
+}
+
 func (p *Proxy) processWebhookEvent(msg websocket.IncomingMessage) {
 	if msg.WebhookEvent == nil {
 		p.cfg.Log.Debug("WebSocket specified for Webhooks received non-webhook event")
@@ -263,9 +286,12 @@ func (p *Proxy) processWebhookEvent(msg websocket.IncomingMessage) {
 	}
 
 	if p.events["*"] || p.events[evt.Type] {
-		if p.cfg.PrintJSON {
+		switch {
+		case p.cfg.PrintJSON:
 			fmt.Println(webhookEvent.EventPayload)
-		} else {
+		case len(p.cfg.Format) > 0:
+			p.formatOutput(p.cfg.Format, webhookEvent.EventPayload)
+		default:
 			maybeConnect := ""
 			if evt.isConnect() {
 				maybeConnect = "connect "
@@ -417,6 +443,8 @@ const (
 	maxHeaderValueSize = 200
 )
 
+const outputFormatJSON = "JSON"
+
 //
 // Private functions
 //