refactor: Move source query parsing logic to listen package

pkg/cmd/listen.go

@@ -88,9 +88,9 @@ func newListenCmd() *listenCmd {
 
 // listenCmd represents the listen command
 func (lc *listenCmd) runListenCmd(cmd *cobra.Command, args []string) error {
-	var sourceQueryString, connectionQuery string
+	var sourceQuery, connectionQuery string
 	if len(args) > 1 {
-		sourceQueryString = args[1]
+		sourceQuery = args[1]
 	}
 	if len(args) > 2 {
 		connectionQuery = args[2]
@@ -112,18 +112,6 @@ func (lc *listenCmd) runListenCmd(cmd *cobra.Command, args []string) error {
 		url.Scheme = "http"
 	}
 
-	var sourceQuery []string
-	if sourceQueryString == "" {
-		sourceQuery = []string{}
-	} else {
-		sourceQuery = strings.Split(sourceQueryString, ",")
-	}
-
-	// TODO: remove once we can support better limit
-	if len(sourceQuery) > 10 {
-		return errors.New("max 10 sources supported")
-	}
-
 	return listen.Listen(url, sourceQuery, connectionQuery, listen.Flags{
 		NoWSS: lc.noWSS,
 	}, &Config)

pkg/listen/listen.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"net/url"
 	"regexp"
+	"strings"
 
 	"github.com/hookdeck/hookdeck-cli/pkg/config"
 	"github.com/hookdeck/hookdeck-cli/pkg/login"
@@ -34,10 +35,15 @@ type Flags struct {
 }
 
 // listenCmd represents the listen command
-func Listen(URL *url.URL, sourceAliases []string, connectionQuery string, flags Flags, config *config.Config) error {
+func Listen(URL *url.URL, sourceQuery string, connectionQuery string, flags Flags, config *config.Config) error {
 	var err error
 	var guestURL string
 
+	sourceAliases, err := parseSourceQuery(sourceQuery)
+	if err != nil {
+		return err
+	}
+
 	isMultiSource := len(sourceAliases) > 1 || (len(sourceAliases) == 1 && sourceAliases[0] == "*")
 
 	if config.Profile.APIKey == "" {
@@ -100,6 +106,22 @@ func Listen(URL *url.URL, sourceAliases []string, connectionQuery string, flags
 	return nil
 }
 
+func parseSourceQuery(sourceQuery string) ([]string, error) {
+	var sourceAliases []string
+	if sourceQuery == "" {
+		sourceAliases = []string{}
+	} else {
+		sourceAliases = strings.Split(sourceQuery, ",")
+	}
+
+	// TODO: remove once we can support better limit
+	if len(sourceAliases) > 10 {
+		return []string{}, errors.New("max 10 sources supported")
+	}
+
+	return sourceAliases, nil
+}
+
 func isPath(value string) (bool, error) {
 	is_path, err := regexp.MatchString(`^(\/)+([/a-zA-Z0-9-_%\.\-\_\~\!\$\&\'\(\)\*\+\,\;\=\:\@]*)$`, value)
 	return is_path, err