client: --remotes flag for reading the list of remotes from a file

main.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"bufio"
+	"bytes"
 	"flag"
 	"fmt"
 	"io/ioutil"
@@ -324,6 +326,8 @@ var clientHelp = `
 
     --hostname, Optionally set the 'Host' header (defaults to the host
     found in the server url).
+
+    --remotes, a file to read remotes from (one per line).
 ` + commonHelp
 
 func client(args []string, envPrefix string) {
@@ -339,6 +343,7 @@ func client(args []string, envPrefix string) {
 	hostname := flags.String("hostname", "", "")
 	pid := flags.Bool("pid", false, "")
 	verbose := flags.Bool("v", false, "")
+	flagRemotes := flags.String("remotes", "", "")
 	flags.Usage = func() {
 		fmt.Print(clientHelp)
 		os.Exit(1)
@@ -347,11 +352,20 @@ func client(args []string, envPrefix string) {
 	flags.Parse(args)
 	//pull out options, put back remaining args
 	args = flags.Args()
-	if len(args) < 2 {
-		log.Fatalf("A server and least one remote is required")
+	switch len(args) {
+	case 0:
+		log.Fatalf("A server is required")
+	case 1:
+		if *flagRemotes == "" {
+			log.Fatalf("A server and least one remote is required")
+		}
 	}
 	config.Server = args[0]
-	config.Remotes = args[1:]
+	//read remotes
+	var err error
+	if config.Remotes, err = readRemotes(args[1:], *flagRemotes); err != nil {
+		log.Fatal(err)
+	}
 	//default auth
 	if config.Auth == "" {
 		config.Auth = os.Getenv("AUTH")
@@ -394,3 +408,36 @@ func flagsFromEnv(fs *flag.FlagSet, prefix string) {
 		f.Value.Set(os.Getenv(prefix + strings.ToUpper(envRepl.Replace(k))))
 	}
 }
+
+func readRemotes(remotes []string, fl string) ([]string, error) {
+	var remotesFn string
+	if fl != "" {
+		remotesFn = fl
+	} else if len(remotes) == 1 && (remotes[0] == "-" || remotes[0] == "") {
+		remotes = remotes[:0]
+		remotesFn = "-"
+	}
+	if remotesFn == "" {
+		return remotes, nil
+	}
+	fh := os.Stdin
+	if remotesFn != "-" {
+		var err error
+		if fh, err = os.Open(remotesFn); err != nil {
+			return remotes, nil
+		}
+	}
+	scanner := bufio.NewScanner(fh)
+	for scanner.Scan() {
+		line := scanner.Bytes()
+		if i := bytes.IndexByte(line, '#'); i >= 0 {
+			line = line[:i]
+		}
+		line = bytes.TrimSpace(line)
+		if len(line) != 0 {
+			remotes = append(remotes, string(line))
+		}
+	}
+	fh.Close()
+	return remotes, nil
+}