Merge pull request #19 from ichikaway/issue-17-silent-mode

Issue #17 silent mode
close #17

Author: ichikaway

NSchecker.go

@@ -2,18 +2,18 @@ package main
 
 import (
 	"flag"
-	"fmt"
 	"nschecker/checker"
 	"nschecker/notification"
+	"nschecker/printer"
 	"os"
 )
 
 var VERSION = "1.0.2"
 
 func showError() {
-	fmt.Printf("USAGE: go run NsCheck.go -type NS -domain domainName -expect 'ns records' \n")
-	fmt.Printf(" or  \n")
-	fmt.Printf("USAGE (Deplicated): go run NsCheck.go type(NS or MX) 'domain' 'ns records' \n")
+	printer.ErrorPrintf("USAGE: go run NsCheck.go -type NS -domain domainName -expect 'ns records' \n")
+	printer.ErrorPrintf(" or  \n")
+	printer.ErrorPrintf("USAGE (Deplicated): go run NsCheck.go type(NS or MX) 'domain' 'ns records' \n")
 	os.Exit(1)
 }
 
@@ -22,26 +22,33 @@ func main() {
 	var domainName string
 	var nsListString string
 
-	fmt.Printf("=== NSchecker Version: %s === \n", VERSION)
 	if len(os.Args) < 4 {
+		showVersion()
 		showError()
 	}
 
 	if len(os.Args) != 4 {
 		qType2 := flag.String("type", "NS", "type: NS or MX")
 		domainName2 := flag.String("domain", "", "domain name: vaddy.net")
 		nsListString2 := flag.String("expect", "", "ex: 'ns1.vaddy.net, ns2.vaddy.net'")
+		mode := flag.String("mode", "", "optional: silent")
 		flag.Parse()
 
 		qType = *qType2
 		domainName = *domainName2
 		nsListString = *nsListString2
+
+		if *mode == "silent" {
+			printer.SilentModeOn()
+		}
 	} else {
 		qType = os.Args[1]
 		domainName = os.Args[2]
 		nsListString = os.Args[3]
 	}
 
+	showVersion()
+
 	if qType != "NS" && qType != "MX" {
 		showError()
 	}
@@ -56,8 +63,12 @@ func main() {
 }
 
 func infoDump(domainName string, qType string, nsListString string) {
-	fmt.Println(" - Domain: " + domainName)
-	fmt.Println(" - Type: " + qType)
-	fmt.Println(" - List: " + nsListString)
-	fmt.Println("")
+	printer.Printf(" - Domain: %s\n", domainName)
+	printer.Printf(" - Type: %s\n", qType)
+	printer.Printf(" - List: %s\n", nsListString)
+	printer.Printf("")
+}
+
+func showVersion() {
+	printer.Printf("=== NSchecker Version: %s === \n", VERSION)
 }

README.md

@@ -47,6 +47,13 @@ go run NSchecker.go -type Type(NS/MX) -domain <your domain> -expect <NS records
 ./nschecker-linux-64bit -type NS -domain "vaddy.net"  -expect "ns-1151.awsdns-15.org. , ns-1908.awsdns-46.co.uk. , ns-457.awsdns-57.com. , ns-700.awsdns-23.net." 
 ```
 
+## options
+### silent mode option
+`-mode silent` no message to stdout. only output error messages to stderr.
+```
+./nschecker-linux-64bit -type NS -domain "vaddy.net"  -expect "ns-1151.awsdns-15.org" -mode silent 
+```
+
 ## Results
 Return status code 0 if there is no problem.  
 Return status code 1 or higher with error message if there there are problems.

checker/checker.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net"
 	"nschecker/dnsmsg"
+	"nschecker/printer"
 	"strings"
 )
 
@@ -37,7 +38,7 @@ func getNsRecords(domainName string) ([]string, error) {
 
 func getMxRecords(domainName string) ([]string, error) {
 	var ret []string
-	fmt.Print(" ..lookup from local DNS cache server.\n\n")
+	printer.Printf(" ..lookup from local DNS cache server.\n\n")
 	nss, err := net.LookupMX(domainName)
 	if err != nil {
 		return nil, errors.New("MX Lookup Error.\n")
@@ -83,6 +84,6 @@ func CheckRecord(qType string, domainName string, expectString string) error {
 			return errors.New("Error: not match DNS record value.\n" + message)
 		}
 	}
-	fmt.Println("PASS.  No problems.")
+	printer.Printf("PASS.  No problems.\n")
 	return nil
 }

dnsmsg/lookup.go

@@ -2,18 +2,18 @@ package dnsmsg
 
 import (
 	"errors"
-	"fmt"
 	"net"
+	"nschecker/printer"
 	"strings"
 )
 
 func Lookup(domainName string) ([]string, error) {
 	server, err := getAuthorityServerName(domainName)
 	if err != nil {
-		fmt.Print(" ..lookup from local DNS cache server.\n\n")
+		printer.Printf(" ..lookup from local DNS cache server.\n\n")
 		return lookupFromDnsCacheServer(domainName)
 	}
-	fmt.Printf(" ..lookup from DNS root server: %s \n\n", server)
+	printer.Printf(" ..lookup from DNS root server: %s \n\n", server)
 	return lookupFromDnsRoot(domainName, server)
 }
 

notification/slack.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"nschecker/printer"
 	"os"
 )
 
@@ -73,7 +74,7 @@ func PostSlack(title, text string, domain string, qType string) {
 		return
 	}
 
-	fmt.Println("Sending warning message to slack.")
+	printer.Printf("Sending warning message to slack.\n")
 
 	params := createSlackMessage(title, text, domain, qType)
 

printer/default.go

@@ -0,0 +1,22 @@
+package printer
+
+import (
+	"fmt"
+)
+
+var handlePrintf = defaultPrintf
+
+func Printf(format string, a ...interface{}) {
+	handlePrintf(format, a...)
+}
+
+func SilentModeOn() {
+	handlePrintf = printerNothing
+}
+
+func defaultPrintf(format string, a ...interface{}) {
+	fmt.Printf(format, a...)
+}
+
+func printerNothing(format string, a ...interface{}) {
+}

printer/error.go

@@ -0,0 +1,10 @@
+package printer
+
+import (
+	"fmt"
+	"os"
+)
+
+func ErrorPrintf(format string, a ...interface{}) {
+	fmt.Fprintf(os.Stderr, format, a...)
+}