Change error handling for sort configuration

mailq/queue.go

@@ -4,6 +4,14 @@ import (
 	"time"
 )
 
+type MailQ struct {
+	NumTotal    int
+	NumActive   int
+	NumHold     int
+	NumDeferred int
+	Entries     []QEntry
+}
+
 type QEntry struct {
 	Id         string
 	Status     string
@@ -13,11 +21,3 @@ type QEntry struct {
 	Recipients []string
 	Reason     string
 }
-
-type MailQ struct {
-	NumTotal    int
-	NumActive   int
-	NumHold     int
-	NumDeferred int
-	Entries     []QEntry
-}

mailq/sorting.go

@@ -1,6 +1,7 @@
 package mailq
 
 import (
+	"errors"
 	"fmt"
 	"sort"
 )
@@ -29,16 +30,16 @@ func isQEntryAttribute(attributeName string) bool {
 	return isValidAttribute
 }
 
-func (c qEntrySortConfig) By(attributeName string, order string) qEntrySortConfig {
+func (c qEntrySortConfig) By(attributeName string, order string) (qEntrySortConfig, error) {
 	if !isQEntryAttribute(attributeName) {
-		panic(fmt.Sprintf("Invalid sort attribute: '%s' given!", attributeName))
+		return c, errors.New(fmt.Sprintf("Invalid sort attribute: '%s' given!", attributeName))
 	}
 	if order != "ASC" && order != "DESC" {
-		panic(fmt.Sprintf("Invalid sort order '%s' given!", order))
+		return c, errors.New(fmt.Sprintf("Invalid sort order '%s' given!", order))
 	}
 	newAttributeConfig := qEntryAttributeSortConfig{attribute: attributeName, order: order}
 	c.attributes = append(c.attributes, newAttributeConfig)
-	return c
+	return c, nil
 }
 
 func (queue MailQ) Sort(config qEntrySortConfig) {

main.go

@@ -49,7 +49,10 @@ func showQueue() {
 		fmt.Printf("Could not fetch queue entries: %s\n", err.Error())
 		os.Exit(1)
 	}
-	sortConfig := mailq.NewSortConfig().By("Status", "ASC").By("Sender", "ASC").By("Recipients", "DESC")
+	sortConfig := mailq.NewSortConfig()
+	sortConfig.By("Status", "ASC")
+	sortConfig.By("Sender", "ASC")
+	sortConfig.By("Recipients", "DESC")
 	queue.Sort(sortConfig)
 	if settings["usePager"] == "true" {
 		pagerReader, pagerWriter := io.Pipe()