basic HTTP server

.gitignore

@@ -50,3 +50,4 @@ echoserver/echoserver
 example-redis/example-redis
 echorot13/echorot13
 chatserver/chatserver
+example-httptcp/example-httptcp

example-httptcp/main.go

@@ -0,0 +1,160 @@
+package main
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"strings"
+)
+
+type HttpRequest struct {
+	Method  string
+	Url     string
+	Proto   string
+	Version string
+	Headers map[string]string
+	Body    string
+}
+
+type HttpResponse struct {
+	Proto  string
+	Code   int
+	Status string
+	Body   string
+}
+
+func checkMethod(m string) error {
+	switch m {
+	case "GET":
+	case "POST":
+	case "PUT":
+	case "HEAD":
+	case "DELETE":
+	case "OPTIONS":
+	default:
+		return errors.New("Unknown method")
+	}
+	return nil
+}
+func checkProto(p string) error {
+	switch p {
+	case "HTTP/1.1":
+	case "HTTP/1.0":
+	default:
+		return errors.New("Unknown proto")
+	}
+	return nil
+}
+
+func (req *HttpRequest) parseRequestLine(line string) error {
+	parts := strings.Fields(line)
+	if len(parts) != 3 {
+		return errors.New("Invalid request line")
+	}
+	for i, p := range parts {
+		switch i {
+		case 0:
+			if err := checkMethod(p); err != nil {
+				return err
+			}
+			req.Method = p
+		case 1:
+			req.Url = p
+		case 2:
+			if err := checkProto(p); err != nil {
+				return err
+			}
+			req.Proto = p
+		}
+	}
+	req.Headers = make(map[string]string)
+	return nil
+}
+func (req *HttpRequest) parseHeader(line string) error {
+	parts := strings.Fields(line)
+	if len(parts) < 2 {
+		return errors.New("Invalid header")
+	}
+	name := parts[0]
+	if !strings.HasSuffix(name, ":") {
+		return errors.New("Invalid header")
+	}
+	value := strings.Join(parts[1:], " ")
+	req.Headers[name[:len(name)-1]] = value
+	return nil
+}
+func (req *HttpRequest) appendBody(line string) error {
+	req.Body += line + "\n"
+	return nil
+}
+func (req *HttpRequest) handleRequest() *HttpResponse {
+	resp := &HttpResponse{
+		Proto:  req.Proto,
+		Code:   200,
+		Status: "OK",
+		Body:   "URL = " + req.Url + "\n",
+	}
+	return resp
+}
+func (resp *HttpResponse) String() string {
+	return fmt.Sprintf("%s %d %s\r\nContent-Length: %d\r\n\r\n%s",
+		resp.Proto, resp.Code, resp.Status, len(resp.Body), resp.Body)
+}
+
+func handle(conn net.Conn) {
+	defer conn.Close()
+
+	req := new(HttpRequest)
+	scanner := bufio.NewScanner(conn)
+	requestLine := true
+	headers := false
+	for scanner.Scan() {
+		line := scanner.Text()
+		if requestLine {
+			fmt.Println("Request line:", line)
+			if err := req.parseRequestLine(line); err != nil {
+				log.Fatalln("error request line", err) // TODO response error
+			}
+			requestLine, headers = false, true
+		} else if headers {
+			if line == "" {
+				fmt.Println("End headers")
+				headers = false
+				break
+			} else {
+				fmt.Println("Header:", line)
+				if err := req.parseHeader(line); err != nil {
+					log.Println("error header", err)
+				}
+			}
+		} else {
+			break
+			/*
+				if err := req.appendBody(line); err != nil {
+					log.Println("error body", err)
+				}
+			*/
+		}
+	}
+	resp := req.handleRequest()
+	io.WriteString(conn, resp.String())
+}
+
+func main() {
+	server, err := net.Listen("tcp", ":9000")
+	if err != nil {
+		log.Fatalln(err)
+	}
+	defer server.Close()
+
+	for {
+		conn, err := server.Accept()
+		if err != nil {
+			log.Fatalln(err)
+		}
+		go handle(conn)
+	}
+}