all: rewrite all codes to use "var" instead of ":="

Using ":=" simplify the code but we lose the type.  For example,

  v := F()

The only way we know what the type of v is by inspecting the function
F.
Another disadvantages of using ":=" may cause extra variables
allocation where two or more variables with same type is declared
inside body of function where it could be only one.

While at it, we split the struct for test case into separate type.

1 files changed, 40 insertions, 24 deletions

diff --git a/lib/dns/server_example_test.go b/lib/dns/server_example_test.go
index 1ef729c2..e82c36ee 100644
--- a/lib/dns/server_example_test.go
+++ b/lib/dns/server_example_test.go
@@ -1,59 +1,75 @@
-package dns_test
+// Copyright 2021, Shulhan <ms@kilabit.info>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package dns
 
 import (
 	"fmt"
 	"log"
 	"time"
-
-	"github.com/shuLhan/share/lib/dns"
 )
 
 func clientLookup(nameserver string) {
-	cl, err := dns.NewUDPClient(nameserver)
+	var (
+		q = MessageQuestion{
+			Name: "kilabit.info",
+		}
+
+		cl  *UDPClient
+		msg *Message
+		rr  ResourceRecord
+		err error
+		x   int
+	)
+
+	cl, err = NewUDPClient(nameserver)
 	if err != nil {
 		log.Println(err)
 		return
 	}
 
-	q := dns.MessageQuestion{
-		Name: "kilabit.info",
-	}
-	msg, err := cl.Lookup(q, false)
+	msg, err = cl.Lookup(q, false)
 	if err != nil {
 		log.Println(err)
 		return
 	}
 
 	fmt.Printf("Receiving DNS message: %s\n", msg)
-	for x, answer := range msg.Answer {
-		fmt.Printf("Answer %d: %s\n", x, answer.Value)
+	for x, rr = range msg.Answer {
+		fmt.Printf("Answer %d: %s\n", x, rr.Value)
 	}
-	for x, auth := range msg.Authority {
-		fmt.Printf("Authority %d: %s\n", x, auth.Value)
+	for x, rr = range msg.Authority {
+		fmt.Printf("Authority %d: %s\n", x, rr.Value)
 	}
-	for x, add := range msg.Additional {
-		fmt.Printf("Additional %d: %s\n", x, add.Value)
+	for x, rr = range msg.Additional {
+		fmt.Printf("Additional %d: %s\n", x, rr.Value)
 	}
 }
 
 func ExampleServer() {
-	serverAddress := "127.0.0.1:5300"
+	var (
+		serverAddress = "127.0.0.1:5300"
+		serverOptions = &ServerOptions{
+			ListenAddress:    "127.0.0.1:5300",
+			HTTPPort:         8443,
+			TLSCertFile:      "testdata/domain.crt",
+			TLSPrivateKey:    "testdata/domain.key",
+			TLSAllowInsecure: true,
+		}
 
-	serverOptions := &dns.ServerOptions{
-		ListenAddress:    "127.0.0.1:5300",
-		HTTPPort:         8443,
-		TLSCertFile:      "testdata/domain.crt",
-		TLSPrivateKey:    "testdata/domain.key",
-		TLSAllowInsecure: true,
-	}
+		server   *Server
+		zoneFile *Zone
+		err      error
+	)
 
-	server, err := dns.NewServer(serverOptions)
+	server, err = NewServer(serverOptions)
 	if err != nil {
 		log.Fatal(err)
 	}
 
 	// Load records to be served from zone file.
-	zoneFile, err := dns.ParseZoneFile("testdata/kilabit.info", "", 0)
+	zoneFile, err = ParseZoneFile("testdata/kilabit.info", "", 0)
 	if err != nil {
 		log.Fatal(err)
 	}