Refactoring move methods to separate packages add optional arguments

.gitignore

@@ -1 +1,3 @@
 *.iml
+*.log
+main

block.yaml

@@ -160,7 +160,8 @@ block:
   - '.*apenterprise.io.*'
   - '.*.netdna-ssl.com.*'
   - '.*.demandbase.com.*'
-  - '.*.wp.com.*'
+  - '.stats.wp.com.*'
+  - '.pixel.wp.com.*'
   - '.*.clicktale.net.*'
   - '.*.report-uri.com.*'
   - '.*.algolia.com.*'

main.go

@@ -1,119 +1,50 @@
 package main
 
 import (
+	"./proxy"
 	"crypto/tls"
-	"gopkg.in/yaml.v2"
 	"fmt"
-	"io"
-	"io/ioutil"
-	"log"
-	"net"
+	"github.com/akamensky/argparse"
 	"net/http"
-	"regexp"
-	"time"
+	"os"
 )
-/*Based on
-https://github.com/bechurch/reverse-proxy-demo
-https://github.com/txn2/p3y/blob/master/p3y.go
-https://medium.com/@mlowicki/http-s-proxy-in-golang-in-less-than-100-lines-of-code-6a51c2f2c38c
-*/
 
-type conf struct {
-	Entries []string `yaml:"block"`
-}
-
-//https
-func handleTunneling(res http.ResponseWriter, req *http.Request) {
-	dest_conn, err := net.DialTimeout("tcp", req.Host, 10*time.Second)
+func readArgs() (string, string, string) {
+	parser := argparse.NewParser("blocking-http-proxy", "HTTP/S proxy that blocks")
+	host := parser.String("", "host", &argparse.Options{Help: "host", Required: false})
+	port := parser.String("", "port", &argparse.Options{Help: "port", Required: false})
+	blockFile := parser.String("", "block", &argparse.Options{Help: "YAML block file", Required: false})
+	err := parser.Parse(os.Args)
 	if err != nil {
-		http.Error(res, err.Error(), http.StatusServiceUnavailable)
-		return
+		fmt.Println(parser.Usage(err))
 	}
-	res.WriteHeader(http.StatusOK)
-	hijacker, ok := res.(http.Hijacker)
-	if !ok {
-		http.Error(res, "Hijacking not supported", http.StatusInternalServerError)
-		return
+	if *host == "" {
+		*host = "0.0.0.0"
 	}
-	client_conn, _, err := hijacker.Hijack()
-	if err != nil {
-		http.Error(res, err.Error(), http.StatusServiceUnavailable)
+	if *port == "" {
+		*port = "11666"
 	}
-	go transfer(dest_conn, client_conn)
-	go transfer(client_conn, dest_conn)
-}
-func transfer(destination io.WriteCloser, source io.ReadCloser) {
-	defer destination.Close()
-	defer source.Close()
-	io.Copy(destination, source)
-}
-
-// http
-func copyHeader(dst, src http.Header) {
-	for k, vv := range src {
-		for _, v := range vv {
-			dst.Add(k, v)
-		}
+	if *blockFile == "" {
+		*blockFile = "block.yaml"
 	}
-}
-
-func handleRequestCustom(res http.ResponseWriter, req *http.Request) {
-	transport := http.DefaultTransport
-	out, err := transport.RoundTrip(req)
-	if err != nil {
-		http.Error(res, err.Error(), http.StatusServiceUnavailable)
-		return
-	}
-	copyHeader(res.Header(), out.Header)
-	res.WriteHeader(out.StatusCode)
-	_, err = io.Copy(res, out.Body)
-	if err != nil {
-		http.Error(res, err.Error(), http.StatusInternalServerError)
-		return
-	}
-	err = out.Body.Close()
-	if err != nil {
-		http.Error(res, err.Error(), http.StatusInternalServerError)
-		return
-	}
-}
-
-
-func loadBlockedList(filename string) []regexp.Regexp {
-	var c conf
-	yamlFile, err := ioutil.ReadFile(filename)
-	if err != nil {
-		log.Printf("yamlFile.Get err   #%v ", err)
-	}
-	err = yaml.Unmarshal(yamlFile, &c)
-	regexps := []regexp.Regexp{}
-	for _, condition := range c.Entries {
-		//log.Printf("%s", condition)
-		r := regexp.MustCompile(condition)
-		regexps = append(regexps, *r)
-	}
-	return regexps
-}
-
-func shouldBlock(regList []regexp.Regexp, url string) bool {
-	for _, condition := range regList {
-		if condition.MatchString(url) {
-			return true
-		}
-	}
-	return false
+	return *host, *port, *blockFile
 }
 
 func main() {
-	port :=  "0.0.0.0:11666"
-	log.Printf("Server will run on: %s\n", port)
-	http.HandleFunc("/", handleRequestCustom)
-	regList := loadBlockedList("block.yaml")
+	logger := proxy.NewLogger()
+	blockedLogger := proxy.NewFileLogger("block.log")
+	allowLogger := proxy.NewFileLogger("allow.log")
+	host, port, blockFile := readArgs()
+	address :=  host+":"+port
+	c := proxy.NewConfig()
+	fmt.Println(len(os.Args), os.Args)
+	logger.Printf("Server will run on: %s\n", address)
+	regList := c.LoadBlockedList(blockFile)
 	server := &http.Server{
-		Addr: port,
+		Addr: address,
 		Handler: http.HandlerFunc(func(res http.ResponseWriter, req *http.Request) {
-			if shouldBlock(regList, req.Host) {
-				//log.Printf("Blocked %s\n", req.Host)
+			if proxy.ShouldBlock(regList, req.Host) {
+				blockedLogger.WriteLine("Blocked %s\n", false, req.Host)
 				if wr, ok := res.(http.Hijacker); ok {
 					conn, _, err := wr.Hijack()
 					if err != nil {
@@ -123,11 +54,11 @@ func main() {
 				}
 			} else {
 				if req.Method == http.MethodConnect {
-					log.Printf("proxy_url: %s\n", req.Host)
-					handleTunneling(res, req)
+					allowLogger.WriteLine("proxy_url: %s\n", true, req.Host)
+					proxy.HandleTunneling(res, req)
 				} else {
-					log.Printf("proxy_url: %s%s\n", req.Host, req.RequestURI)
-					handleRequestCustom(res, req)
+					allowLogger.WriteLine("proxy_url: %s %s\n", true, req.Host, req.RequestURI)
+					proxy.HandleRequestCustom(res, req)
 				}
 			}
 
@@ -135,6 +66,5 @@ func main() {
 		// Disable HTTP/2.
 		TLSNextProto: make(map[string]func(*http.Server, *tls.Conn, http.Handler)),
 	}
-
 	server.ListenAndServe()
 }

proxy/block.go

@@ -0,0 +1,12 @@
+package proxy
+
+import "regexp"
+
+func ShouldBlock(regList []regexp.Regexp, url string) bool {
+	for _, condition := range regList {
+		if condition.MatchString(url) {
+			return true
+		}
+	}
+	return false
+}

proxy/config.go

@@ -0,0 +1,31 @@
+package proxy
+
+import (
+	"io/ioutil"
+	"gopkg.in/yaml.v2"
+	"regexp"
+)
+
+type Config struct {
+	Entries []string `yaml:"block"`
+	log Logger
+}
+
+func NewConfig() *Config {
+	return &Config{Entries: nil, log:Logger{}}
+}
+
+func (c *Config) LoadBlockedList(filename string) []regexp.Regexp {
+	yamlFile, err := ioutil.ReadFile(filename)
+	if err != nil {
+		c.log.Printf("yamlFile.Get err   #%v ", err)
+	}
+	err = yaml.Unmarshal(yamlFile, &c)
+	regexps := []regexp.Regexp{}
+	for _, condition := range c.Entries {
+		//log.Printf("%s", condition)
+		r := regexp.MustCompile(condition)
+		regexps = append(regexps, *r)
+	}
+	return regexps
+}

proxy/http.go

@@ -0,0 +1,35 @@
+package proxy
+
+import (
+	"io"
+	"net/http"
+)
+
+func copyHeader(dst, src http.Header) {
+	for k, vv := range src {
+		for _, v := range vv {
+			dst.Add(k, v)
+		}
+	}
+}
+
+func HandleRequestCustom(res http.ResponseWriter, req *http.Request) {
+	transport := http.DefaultTransport
+	out, err := transport.RoundTrip(req)
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusServiceUnavailable)
+		return
+	}
+	copyHeader(res.Header(), out.Header)
+	res.WriteHeader(out.StatusCode)
+	_, err = io.Copy(res, out.Body)
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	err = out.Body.Close()
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusInternalServerError)
+		return
+	}
+}

proxy/https.go

@@ -0,0 +1,33 @@
+package proxy
+
+import (
+	"io"
+	"net"
+	"net/http"
+	"time"
+)
+
+func HandleTunneling(res http.ResponseWriter, req *http.Request) {
+	dest_conn, err := net.DialTimeout("tcp", req.Host, 10*time.Second)
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusServiceUnavailable)
+		return
+	}
+	res.WriteHeader(http.StatusOK)
+	hijacker, ok := res.(http.Hijacker)
+	if !ok {
+		http.Error(res, "Hijacking not supported", http.StatusInternalServerError)
+		return
+	}
+	client_conn, _, err := hijacker.Hijack()
+	if err != nil {
+		http.Error(res, err.Error(), http.StatusServiceUnavailable)
+	}
+	go transfer(dest_conn, client_conn)
+	go transfer(client_conn, dest_conn)
+}
+func transfer(destination io.WriteCloser, source io.ReadCloser) {
+	defer destination.Close()
+	defer source.Close()
+	io.Copy(destination, source)
+}

proxy/logger.go

@@ -0,0 +1,44 @@
+package proxy
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+type Logger struct{
+
+}
+
+type FileLogger struct {
+	Logger
+	filename string
+}
+
+func NewLogger() *Logger {
+	return &Logger{}
+}
+
+func NewFileLogger(filename string) *FileLogger {
+	if _, err := os.Stat(filename); os.IsNotExist(err) {
+		os.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0666)
+	}
+	return &FileLogger{filename: filename}
+}
+
+func (l *FileLogger) WriteLine(msg string, print bool, v ...interface{}) {
+	f, err := os.OpenFile(l.filename, os.O_APPEND|os.O_WRONLY, 0600)
+	if err != nil {
+		panic(err)
+	}
+	line := fmt.Sprintf(msg, v...)
+	if print {
+		log.Printf(msg, v...)
+	}
+	f.WriteString(line)
+	defer f.Close()
+}
+
+func (l *Logger) Printf(msg string, v ...interface{}) {
+	log.Printf(msg, v...)
+}