Refactoring

main.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"os/exec"
 	"strconv"
-	"text/tabwriter"
 )
 
 import (
@@ -30,10 +29,12 @@ func parseArguments() {
 	mailqCommandPtr := flag.String("mailqCommand", "mailq", "Command to use for getting mailq output")
 	mailqCommandArgsPtr := flag.String("mailqCommandArgs", "", "Optional arguments to pass to mailqCommand")
 	interactivePtr := flag.Bool("interactive", false, "Set to true for shell mode")
+	machineFormatPtr := flag.Bool("machineFormat", false, "Set to true to get output suitable for cut/awk/...")
 	flag.Parse()
 	settings["mailqCommand"] = *mailqCommandPtr
 	settings["mailqCommandArgs"] = *mailqCommandArgsPtr
 	settings["interactive"] = strconv.FormatBool(*interactivePtr)
+	settings["machineFormat"] = strconv.FormatBool(*machineFormatPtr)
 }
 
 func interactiveShell() {
@@ -49,35 +50,12 @@ func showQueue() {
 	pagerReader, pagerWriter := io.Pipe()
 	pagerDone := make(chan bool)
 	go launchPager(pagerReader, pagerDone)
-	printQueueEntries(queue, pagerWriter)
+	queue.PrintHumanReadable(pagerWriter)
 	pagerWriter.Close()
 	// Wait for pager to be closed before continuing the main program
 	<-pagerDone
 }
 
-func fetchQueue() (parser.MailQ, error) {
-	if settings["mailqCommandArgs"] == "" {
-		return readFromCmd(exec.Command(settings["mailqCommand"]))
-	} else {
-		return readFromCmd(exec.Command(settings["mailqCommand"], settings["mailqCommandArgs"]))
-	}
-}
-
-func printQueueEntries(queue parser.MailQ, writer io.Writer) {
-	fmt.Fprintf(writer, "%d entries total (%d active, %d deferred, %d on hold)\n\n", len(queue.Entries), queue.NumActive, queue.NumDeferred, queue.NumHold)
-	tabWriter := tabwriter.NewWriter(writer, 2, 2, 1, ' ', tabwriter.TabIndent)
-	fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| \n", "Date", "Id", "Status", "Size", "Sender", "#", "First Recipient", "Reason")
-	for _, entry := range queue.Entries {
-		_, writeError := fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %d\t| %s\t| {%d}\t| %s\t| %s\t| \n", entry.Date.Format(parser.SortableDateFormat), entry.Id, entry.Status, entry.Size, entry.Sender, len(entry.Recipients), entry.Recipients[0], entry.Reason)
-		if writeError != nil {
-			// A writeError is expected once the reader was closed
-			// This happens when the pager application got terminated
-			break
-		}
-	}
-	tabWriter.Flush()
-}
-
 func launchPager(reader *io.PipeReader, pagerDone chan<- bool) {
 	cmd := exec.Command("less", "--chop-long-lines")
 	cmd.Stdin = reader
@@ -93,6 +71,14 @@ func launchPager(reader *io.PipeReader, pagerDone chan<- bool) {
 	}
 }
 
+func fetchQueue() (parser.MailQ, error) {
+	if settings["mailqCommandArgs"] == "" {
+		return readFromCmd(exec.Command(settings["mailqCommand"]))
+	} else {
+		return readFromCmd(exec.Command(settings["mailqCommand"], settings["mailqCommandArgs"]))
+	}
+}
+
 func readFromCmd(cmd *exec.Cmd) (parser.MailQ, error) {
 	stdout, err := cmd.StdoutPipe()
 	if err != nil {

parser/parser.go

@@ -8,6 +8,7 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
+	"text/tabwriter"
 	"time"
 )
 
@@ -31,10 +32,6 @@ type MailQ struct {
 
 const SortableDateFormat = "2006-01-02 15:04:05"
 
-func (m QEntry) ShortString() string {
-	return fmt.Sprintf("[%s] %s <%s> -> %d recipients (%d bytes)", m.Date.Format(SortableDateFormat), m.Id, m.Sender, len(m.Recipients), m.Size)
-}
-
 func (m QEntry) String() string {
 	var recipientSuffix string
 	if len(m.Recipients) > 1 {
@@ -43,6 +40,10 @@ func (m QEntry) String() string {
 	return fmt.Sprintf("[%s] %s <%s> -> {%d}<%s>%s (%s, %d bytes)", m.Date.Format(SortableDateFormat), m.Id, m.Sender, len(m.Recipients), m.Recipients[0], recipientSuffix, m.Status, m.Size)
 }
 
+func (m QEntry) MachineReadableString() string {
+	return fmt.Sprintf("%s_%d_%s_%s_%s", m.Id, m.Status, m.Date.Format(SortableDateFormat), m.Size, m.Sender, m.Reason, strings.Join(m.Recipients, ","))
+}
+
 func (m QEntry) DetailedString() string {
 	var reasonStr string
 	if m.Reason == "" {
@@ -51,6 +52,30 @@ func (m QEntry) DetailedString() string {
 	return fmt.Sprintf("Id: %s\nDate: %s\nStatus: %s\nReason: %s\nSize: %d\nSender: %s\nRecipients: %s", m.Id, m.Date.Format(SortableDateFormat), m.Status, reasonStr, m.Size, m.Sender, strings.Join(m.Recipients, ", "))
 }
 
+func (queue MailQ) PrintMachineReadable(writer io.Writer) {
+	for _, entry := range queue.Entries {
+		fmt.Fprintf(writer, "%s\n", entry.MachineReadableString())
+	}
+}
+
+func (queue MailQ) PrintHumanReadable(writer io.Writer) {
+	if len(queue.Entries) == 0 {
+		fmt.Fprintf(writer, "Mail queue is empty\n")
+	} else {
+		fmt.Fprintf(writer, "%d entries total (%d active, %d deferred, %d on hold)\n\n", len(queue.Entries), queue.NumActive, queue.NumDeferred, queue.NumHold)
+		tabWriter := tabwriter.NewWriter(writer, 2, 2, 1, ' ', tabwriter.TabIndent)
+		fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| \n", "Date", "Id", "Status", "Size", "Sender", "#", "First Recipient", "Reason")
+		for _, entry := range queue.Entries {
+			_, writeError := fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %d\t| %s\t| {%d}\t| %s\t| %s\t| \n", entry.Date.Format(SortableDateFormat), entry.Id, entry.Status, entry.Size, entry.Sender, len(entry.Recipients), entry.Recipients[0], entry.Reason)
+			if writeError != nil {
+				// A writeError is expected once the reader was closed
+				break
+			}
+		}
+		tabWriter.Flush()
+	}
+}
+
 func ParseMailQ(dataSource io.Reader) (MailQ, error) {
 	const dateFormat = "2006 Mon Jan _2 15:04:05"
 	var messageIdStart = regexp.MustCompile("^[0-9A-Za-z]+[*!]? ")