Feature/83 (#84)

* setup host resolution

* #83 removing unnecessary log

* #83 bump version

VERSION

@@ -1 +1 @@
-2.5.4
+2.6.0

dns.go

@@ -48,7 +48,8 @@ func handleQuestion(respWriter dns.ResponseWriter, reqMsg *dns.Msg) {
 
 	// loading the solvers and try to solve the hostname in that order
 	solvers := []proxy.DnsSolver{
-		proxy.NewDockerSolver(docker.GetCache()),  proxy.NewLocalDNSSolver(store.GetInstance()), proxy.NewRemoteDnsSolver(),
+		proxy.NewSystemSolver(), proxy.NewDockerSolver(docker.GetCache()),
+		proxy.NewLocalDNSSolver(store.GetInstance()), proxy.NewRemoteDnsSolver(),
 	}
 
 	for _, solver := range solvers {

docker-compose.yml

@@ -4,7 +4,6 @@ services:
   # Base Image to build project
   compiler-dps:
     image: golang:1.9
-    container_name: gocompiler-dps
     working_dir: /app/src/github.com/mageddo/dns-proxy-server
     volumes:
       - $PWD:/app/src/github.com/mageddo/dns-proxy-server

docs/developing/Developing-at-the-project.md

@@ -2,11 +2,11 @@
 
 Setup the environment
 
-    $ docker-compose up -d compiler-dps && docker exec -it gocompiler-dps bash
+    $ docker-compose up -d compiler-dps && docker-compose exec compiler-dps bash
 
 Running the application 
 
-    go run src/dns.go
+    go run dns.go
 
 Running unit tests
 

proxy/system.go

@@ -0,0 +1,54 @@
+package proxy
+
+import (
+	"errors"
+		"github.com/mageddo/go-logging"
+	"github.com/miekg/dns"
+	"golang.org/x/net/context"
+	"net"
+	"strconv"
+	"strings"
+		"github.com/mageddo/dns-proxy-server/utils"
+	"regexp"
+)
+
+type SystemDnsSolver struct {}
+
+func (s SystemDnsSolver) Solve(ctx context.Context, question dns.Question) (*dns.Msg, error) {
+
+	questionName := question.Name[:len(question.Name)-1]
+	switch questionName {
+	case "host.docker":
+		ip, err, code := utils.Exec("sh", "-c", "ip r | awk '/default/{print $3}'")
+		if code == 0 {
+			clearedIP := regexp.MustCompile(`\s`).ReplaceAllLiteralString(string(ip), ``)
+			logging.Infof("status=solved, solver=system, question=%s, ip=%s", questionName, clearedIP)
+			return s.getMsg(questionName, clearedIP, question), nil
+		}
+		logging.Errorf("status=not-solved, solver=system, question=%s", questionName, err)
+		return nil, err
+	}
+	return nil, errors.New("host not found")
+}
+
+
+func NewSystemSolver() SystemDnsSolver {
+	return SystemDnsSolver{}
+}
+
+func (s SystemDnsSolver) getMsg(key, ip string, question dns.Question) *dns.Msg {
+	ipArr := strings.Split(ip, ".")
+	i1, _ := strconv.Atoi(ipArr[0])
+	i2, _ := strconv.Atoi(ipArr[1])
+	i3, _ := strconv.Atoi(ipArr[2])
+	i4, _ := strconv.Atoi(ipArr[3])
+
+	rr := &dns.A{
+		Hdr: dns.RR_Header{Name: question.Name, Rrtype: dns.TypeA, Class: dns.ClassINET, Ttl: 0},
+		A:   net.IPv4(byte(i1), byte(i2), byte(i3), byte(i4)),
+	}
+
+	m := new(dns.Msg)
+	m.Answer = append(m.Answer, rr)
+	return m
+}