HTTP communication using Socket module

A simple example of HTTP communication using the python3 socket module

To put it simply, HTTP is a rule (data is called TCP payload) for the part of TCP data (called TCP payload) that can be any data because HTML files are sent by TCP communication (not necessarily TCP). (Please follow this format), so you can send the data according to that format with recv, send.

Here, proceed while reading RFC7230, RFC7230 Japanese translation.

HTTP communication is communication performed according to a promise called "HTTP". .

Start-line and header-section

About the start line start-line

An HTTP message can be either a client-to-server request or a server-to-client response. The two can be distinguished from each other at this start line. The starting line is the request line in the former case and the [status line](https://help.amanohina. It takes the format com / RFC7230-ja.html#p.status-line).

About header section header-section

This time we will use the following header fields.

Server side

Server
Connection
Content-Type
Content-Length

Client side

Accept
Host
Connection
User-Agent

In fact, I didn't use any header field values this time.

Implementation so far

The values in the code and header clauses are fixed here, but as you know, they are determined dynamically.

Client side request line + header clause

RETURN_PHRASE = '\r\n'
VERSION = 'HTTP/1.1'


def make_request_line(mtd, request_target):
    '''Return http_request-line'''

    request_line = \
        mtd + ' ' + request_target + ' ' + VERSION + RETURN_PHRASE
    return request_line


def make_header_section():
    '''Return http_header-section'''

    field_values = {
        'Host': '192.168.1.200',
        'Accept': 'html/plain',
        'Connection': 'close',
        'User-Agent': 'Suzukaze Browser 1.0'
    }
    header_sc = 'Host:' + field_values['Host'] + RETURN_PHRASE
    header_sc += 'Accept:' + field_values['Accept'] + RETURN_PHRASE
    header_sc += 'Connection:' + field_values['Connection'] + RETURN_PHRASE
    header_sc += 'User-Agent:' + field_values['User-Agent'] + RETURN_PHRASE
    header_sc += RETURN_PHRASE
    return header_sc


mtd = 'GET'
request_target = '/'
request_line = make_request_line(mtd, request_target)

header_section = make_header_section()

print(header_section)

The function make_request_line (method, request target)-> request line returns:

GET / HTTP/1.1

The function make_header_section ()-> header section returns:

Host:192.168.1.200
Accept:html/plain
Connection:close
User-Agent:Suzukaze Browser 1.0
Blank line

Server-side status line + header clause

The code is fixed at 200. So reason_phrases is superfluous but added for the mood.

RETURN_PHRASE = '\r\n'
VERSION = 'HTTP/1.1'


def make_status_line():
    '''Return http_staus_line'''

    reason_phrases = {
        '200': 'OK',
        '403': 'Forbidden',
        '404': 'Not Found',
        '405': 'Method Not Allowed'
    }
    status_line = \
        VERSION + ' ' + '200' + ' ' + reason_phrases['200'] + RETURN_PHRASE
    return status_line


def make_header_section(content_length):
    '''Return http_header_section'''

    field_values = {
        'Server': 'Suzukaze Server 1.0',
        'Date': datetime.now(timezone.utc).strftime(r'%a, %d %b %Y %X %Z'),
        'Connection': 'close',
        'Content-Type': 'html/plain',
        'Content-Length': content_length
    }
    header_sc = 'Date:' + field_values['Date'] + RETURN_PHRASE
    header_sc += 'Server:' + field_values['Server'] + RETURN_PHRASE
    header_sc += 'Connection' + field_values['Connection'] + RETURN_PHRASE
    header_sc += 'Content-Type' + field_values['Content-Type'] + RETURN_PHRASE
    header_sc += 'Content-Length' + field_values['Cotent-Length'] + RETURN_PHRASE
    header_sc += RETURN_PHRASE
    return header_sc


def read_index_html():
    '''Return index.html and that length'''

    with open('index.html', 'rb') as f:
        index_html = f.read()
        index_len = len(index_html)
        return index_html, index_len


status_line = make_status_line()

index_html, index_len = read_index_html()
content_length = index_len

header_section = make_header_section(content_length)

The function `make_status_line ()-> status line` returns:

HTTP/1.1 200 OK

The function `make_header_section (Content-Length value)-> header section` returns:

Date:Mon, 00 Nov 2020 00:00:00 UTC
Server:Suzukaze Server 1.0
Connection:close
Content-Type:html/plain
Content-Length:1224
Blank line

The function `read_index_html ()-> the contents of index.html, the length of index.html` returns:

b"<!DOCTYPE html>\n<head>\n    <meta charset='utf-8'>\n</head>\n<style>\n* 
(Abbreviation)
ab\xe3\x81\xa4\xe3\x81\x84\xe3\x81\xa6</li>\n                <li>\xe5\x95\x8f\xe3\x81\x84\xe5\x90\x88\xe3\x82\x8f\xe3\x81\x9b</li>\n            </ul>\n        </footer>\n    </div>\n</body>\n"

Information that the server needs to retrieve from the request

In this code, we know that the request is a'/', so we don't need a request-target, and we also close the Connection, so we don't have the information that the server needs after all. So the request line and header clause are passed through.

Message-body

Even if we say that we implement the message body on the server side, we have already read index.html as a byte string, so we just attach it to the end of the header clause on the server side. There is no message body on the client side.

It should be noted here that the start line and header clause are Unicode character strings (str type). Since it is necessary to make it a byte-like-object to send it with a socket, convert it.

Client side

mtd = 'GET'
request_target = '/'
request_line = make_request_line(mtd, request_target)

header_section = make_header_section()

http_msg = \
    bytes(request_line, 'utf-8') + bytes(request_line, 'utf-8')

Server side

status_line = make_status_line()

index_html, index_len = read_index_html()
msg_body = index_html
content_length = str(index_len)

header_section = make_header_section(content_length)

http_msg = \
    bytes(status_line, 'utf-8') + bytes(header_section, 'utf-8') + msg_body

Implementation of socket communication

All you have to do now is send this HTTP message to each other.

The code here is based on TCP communication using Socket module-Python3.

Server side

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.bind(SERVER_ADDRESS)
sock.listen(0)

try:
    conn_sock, client_address = sock.accept()
    print_msg('ac', 'The connection accepted.')
    print_msg('i', '{}:{} --------> {}:{}'
              .format(client_address[0], client_address[1],
                      SERVER_ADDRESS[0], SERVER_ADDRESS[1]))

    # Receiving the request
    recd_data = b''
    while True:
        data = conn_sock.recv(32)
        if not data:
            break
        recd_data += data
    print_msg('i', 'Total received: {}'.format(recd_data))

    # Sending the response
    http_msg = make_http_msg()
    remaining = len(http_msg)
    res = 0
    while remaining > 0:
        res = conn_sock.send(http_msg[res:])
        remaining -= res
finally:
    conn_sock.shutdown(socket.SHUT_WR)
    conn_sock.close()
    print_msg('cl', 'The connection closed.')

Client side

You can declare that you will not send any more data to the server side by shutting down after sending the request. (Empty bytes are sent at the socket level, so the server can detect the end of the request by receiving an empty byte.)

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

try:
    sock.connect(SERVER_ADDRESS)
    print_msg('cn', 'The connection accepted')

    # Sending the request
    http_msg = make_http_msg()
    remaining = len(make_http_msg())
    res = 0
    while remaining > 0:
        res = sock.send(http_msg[res:])
        remaining -= res

    sock.shutdown(socket.SHUT_WR)

    # Receiving the response
    recd_data = b''
    while True:
        data = sock.recv(32)
        print(data)
        if not data:
            break
        recd_data += data
finally:
    sock.close()
    print_msg('cl', 'The connection closed.')

Extract data

Client side

For the time being, the client side needs to take out the following two.

Status line information. This is retrieved as a dictionary with the following regular expression.

STS_LINE_PTN = b'''
(?P<version>HTTP/[0-9][.][0-9])[ ]
(?P<status_code>[0-9][0-9][0-9])[ ]
(?P<reason>([!\"#$%&\'()*+,-./0-9:;<=>?@A-Z[\\]^_`a-z{|}~ ]|\t)+)
([\r][\n])
'''

It is necessary to specify re.VERBOSE at compile time. Doing so will ignore whitespace that is not in the character class [].

It is taken out as follows.

{'version': b'HTTP/1.1', 'status_code': b'200', 'reason': b'OK'}

A message body containing the html code. Since the end of the header clause is a blank line rule, get the last index of the part that matches b'\ r \ n \ r \ n' and set that index to start of[start: end]. To generate a new (message body only) byte string. Then decode it to get the original html code. That is, it is equal to the following character string (html_source) on the server side.

with open('sample.html', 'r') as f:
	html_source = f.read()

Server side

So far, there is no information required on the server side.

Display the obtained html like a browser

Here we make a simple html viewer using Pyqt5. The UI is created using a designer, converted to Python3 code with PyQt5 UI code generator 5.15.1, and the code is tampered with. Originally, the logic added by the user is written in a class created separately so that there is no problem even if the UI is rewritten, but this time the UI will not be rewritten, so set it as it is. The browser looks like this: Import this module with the main module that performs socket communication.

`browser_app.py`


import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWebEngineWidgets import QWebEngineView as QWebView


class Ui_dialog(object):
    def setupUi(self, dialog, html_source):
        dialog.setObjectName('dialog')
        dialog.resize(1000, 650)
        self.stackedWidget = QtWidgets.QStackedWidget(dialog)
        self.stackedWidget.setGeometry(QtCore.QRect(10, 50, 980, 590))
        self.stackedWidget.setObjectName('stackedWidget')
        self.page_1 = QtWidgets.QWidget()
        self.page_1.setObjectName('page_1')
        self.webView = QWebView(self.page_1)
        self.webView.setGeometry(QtCore.QRect(0, 0, 980, 590))
        self.webView.setObjectName('webView')
        self.stackedWidget.addWidget(self.page_1)
        self.page_2 = QtWidgets.QWidget()
        self.page_2.setObjectName('page_2')
        self.page_2_title = QtWidgets.QLabel(self.page_2)
        self.page_2_title.setGeometry(QtCore.QRect(370, 60, 240, 50))
        font = QtGui.QFont()
        font.setPointSize(24)
        self.page_2_title.setFont(font)
        self.page_2_title.setObjectName('page_2_title')
        self.page_2_label1 = QtWidgets.QLabel(self.page_2)
        self.page_2_label1.setGeometry(QtCore.QRect(435, 230, 110, 22))
        font = QtGui.QFont()
        font.setPointSize(16)
        self.page_2_label1.setFont(font)
        self.page_2_label1.setObjectName('page_2_label1')
        self.page_2_ip = QtWidgets.QLineEdit(self.page_2)
        self.page_2_ip.setGeometry(QtCore.QRect(435, 262, 110, 28))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.page_2_ip.setFont(font)
        self.page_2_ip.setObjectName('page_2_ip')
        self.page_2_label2 = QtWidgets.QLabel(self.page_2)
        self.page_2_label2.setGeometry(QtCore.QRect(468, 310, 42, 16))
        font = QtGui.QFont()
        font.setPointSize(16)
        self.page_2_label2.setFont(font)
        self.page_2_label2.setObjectName('page_2_label2')
        self.page_2_url = QtWidgets.QLineEdit(self.page_2)
        self.page_2_url.setGeometry(QtCore.QRect(335, 336, 310, 28))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.page_2_url.setFont(font)
        self.page_2_url.setObjectName('page_2_url')
        self.page_2_save = QtWidgets.QPushButton(self.page_2)
        self.page_2_save.setGeometry(QtCore.QRect(425, 384, 130, 40))
        font = QtGui.QFont()
        font.setPointSize(18)
        self.page_2_save.setFont(font)
        self.page_2_save.setObjectName('page_2_save')
        self.stackedWidget.addWidget(self.page_2)
        self.url_lineEdit = QtWidgets.QLineEdit(dialog)
        self.url_lineEdit.setGeometry(QtCore.QRect(10, 10, 666, 30))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.url_lineEdit.setFont(font)
        self.url_lineEdit.setObjectName('url_lineEdit')
        self.search_btn = QtWidgets.QPushButton(dialog)
        self.search_btn.setGeometry(QtCore.QRect(670, 10, 90, 30))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.search_btn.setFont(font)
        self.search_btn.setCursor(QtGui.QCursor(QtCore.Qt.PointingHandCursor))
        self.search_btn.setObjectName('search_btn')
        self.config_btn = QtWidgets.QPushButton(dialog)
        self.config_btn.setGeometry(QtCore.QRect(780, 10, 60, 30))
        font = QtGui.QFont()
        font.setPointSize(10)
        self.config_btn.setFont(font)
        self.config_btn.setObjectName('config_btn')

        # ----------------------------------------------

        self.url_lineEdit.setText('in preparation')
        self.page_2_title.setText('Setting the DNS')
        self.page_2_label1.setText('IP Address')
        self.page_2_ip.setText('in preparation')
        self.page_2_label2.setText('URL')
        self.page_2_url.setText('in preparation')

        self.webView.setHtml(html_source)

        # ----------------------------------------------

        QtCore.QMetaObject.connectSlotsByName(dialog)


def mybrowser(html_source):
    app = QtWidgets.QApplication(sys.argv)
    dialog = QtWidgets.QDialog()
    ui = Ui_dialog()
    ui.setupUi(dialog, html_source)
    dialog.show()
    sys.exit(app.exec_())

Put this in the same directory, import it on the client side and call it as follows.

status_dict, res_msg = status_line_parser(recd_data)

if status_dict['status_code'].decode() == '200':
    html_lines = get_msg_body(res_msg)
    html_lines = html_lines.decode()
    mybrowser(html_lines)

Then

It is displayed like this.

Source code

client.py

`client.py`


import socket
import re
from colored_print import print_msg
from browser_app import mybrowser


# Request


SERVER_ADDRESS = ('192.168.1.201', 8000)
RETURN_PHRASE = '\r\n'
VERSION = 'HTTP/1.1'


def make_request_line(mtd, request_target):
    '''Return http_request-line'''

    request_line = \
        mtd + ' ' + request_target + ' ' + VERSION + RETURN_PHRASE
    return request_line


def make_header_section():
    '''Return http_header-section'''

    field_values = {
        'Host': '192.168.1.200',
        'Accept': 'html/plain',
        'Connection': 'close',
        'User-Agent': 'Suzukaze-Browser-1.0'
    }
    header_sc = 'Host:' + field_values['Host'] + RETURN_PHRASE
    header_sc += 'Accept:' + field_values['Accept'] + RETURN_PHRASE
    header_sc += 'Connection:' + field_values['Connection'] + RETURN_PHRASE
    header_sc += 'User-Agent:' + field_values['User-Agent'] + RETURN_PHRASE
    header_sc += RETURN_PHRASE
    return header_sc


def make_http_msg():
    '''Return http-message'''

    mtd = 'GET'
    request_target = '/'
    request_line = make_request_line(mtd, request_target)

    header_section = make_header_section()

    http_msg = \
        bytes(request_line, 'utf-8') + bytes(header_section, 'utf-8')
    return http_msg


# Response


def status_line_parser(msg_lines):
    '''Return dict of status line and http_msg except status line'''

    STS_LINE_PTN = b'''
    (?P<version>HTTP/[0-9][.][0-9])[ ]
    (?P<status_code>[0-9][0-9][0-9])[ ]
    (?P<reason>([!\"#$%&\'()*+,-./0-9:;<=>?@A-Z[\\]^_`a-z{|}~ ]|\t)+)
    ([\r][\n])
    '''
    p_sts_line = re.compile(STS_LINE_PTN, re.VERBOSE)

    m_sts_line = p_sts_line.match(msg_lines)
    if m_sts_line is not None:
        sts_line_dict = m_sts_line.groupdict()
        return sts_line_dict, msg_lines[m_sts_line.end():]


def get_msg_body(msg_lines):
    '''Return a message body'''
    
    end = msg_lines.rfind(b'\r\n\r\n')
    print(end)
    if end is not -1:
        return msg_lines[end:]
    else:
        raise ValueError('msg_lines is a invalid format')


########################################################################


sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

try:
    sock.connect(SERVER_ADDRESS)
    print_msg('cn', 'The connection accepted')

    # Sending the request
    http_msg = make_http_msg()
    remaining = len(make_http_msg())
    res = 0
    while remaining > 0:
        res = sock.send(http_msg[res:])
        remaining -= res

    sock.shutdown(socket.SHUT_WR)

    # Receiving the response
    recd_data = b''
    while True:
        data = sock.recv(32)
        print(data)
        if not data:
            break
        recd_data += data
finally:
    sock.close()
    print_msg('cl', 'The connection closed.')


status_dict, res_msg = status_line_parser(recd_data)

if status_dict['status_code'].decode() == '200':
    html_lines = get_msg_body(res_msg)
    html_lines = html_lines.decode()
    mybrowser(html_lines)

server.py

`server.py`


import socket
from datetime import datetime, timezone
from colored_print import print_msg


# Response


SERVER_ADDRESS = ('192.168.1.12', 8000)
RETURN_PHRASE = '\r\n'
VERSION = 'HTTP/1.1'


def make_status_line():
    '''Return http_staus-line'''

    reason_phrases = {
        '200': 'OK',
        '403': 'Forbidden',
        '404': 'Not Found',
        '405': 'Method Not Allowed'
    }
    status_line = \
        VERSION + ' ' + '200' + ' ' + reason_phrases['200'] + RETURN_PHRASE
    return status_line


def make_header_section(content_length):
    '''Return http_header-section'''

    field_values = {
        'Server': 'Suzukaze Server 1.0',
        'Date': datetime.now(timezone.utc).strftime(r'%a, %d %b %Y %X %Z'),
        'Connection': 'close',
        'Content-Type': 'html/plain',
        'Content-Length': content_length
    }
    header_sc = 'Date:' + field_values['Date'] + RETURN_PHRASE
    header_sc += 'Server:' + field_values['Server'] + RETURN_PHRASE
    header_sc += 'Connection:' + field_values['Connection'] + RETURN_PHRASE
    header_sc += 'Content-Type:' + field_values['Content-Type'] + RETURN_PHRASE
    header_sc += 'Content-Length:' + field_values['Content-Length'] + RETURN_PHRASE
    header_sc += RETURN_PHRASE
    return header_sc


def read_index_html():
    '''Return index.html and that length'''

    with open('index.html', 'rb') as f:
        index_html = f.read()
        index_len = len(index_html)
        return index_html, index_len


def make_http_msg():
    status_line = make_status_line()

    index_html, index_len = read_index_html()
    msg_body = index_html
    content_length = str(index_len)

    header_section = make_header_section(content_length)

    http_msg = \
        bytes(status_line, 'utf-8') + bytes(header_section, 'utf-8') + msg_body
    return http_msg


###############################################################


sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.bind(SERVER_ADDRESS)
sock.listen(0)

try:
    conn_sock, client_address = sock.accept()
    print_msg('ac', 'The connection accepted.')
    print_msg('i', '{}:{} --------> {}:{}'
              .format(client_address[0], client_address[1],
                      SERVER_ADDRESS[0], SERVER_ADDRESS[1]))

    # Receiving the request
    recd_data = b''
    while True:
        data = conn_sock.recv(32)
        if not data:
            break
        recd_data += data
    print_msg('i', 'Total received: {}'.format(recd_data))

    # Sending the response
    http_msg = make_http_msg()
    remaining = len(http_msg)
    res = 0
    while remaining > 0:
        res = conn_sock.send(http_msg[res:])
        remaining -= res
finally:
    conn_sock.shutdown(socket.SHUT_WR)
    conn_sock.close()
    print_msg('cl', 'The connection closed.')

colored_print.py

`colored_print.py`


from colorama import Fore, Style


def print_msg(header, msg):
    '''header are i that is INFO or e that is ERROR'''

    if header == 'i':
        print(Fore.GREEN + '[INFO]',
              Style.RESET_ALL + msg)
    elif header == 'e':
        print(Fore.RED + '[ERROR]',
              Style.RESET_ALL + msg)
    elif header == 'ac':
        print(Fore.BLUE + '[ACCEPT]',
              Style.RESET_ALL + msg)
    elif header == 'cn':
        print(Fore.BLUE + '[CONNECT]',
              Style.RESET_ALL + msg)
    elif header == 'cl':
        print(Fore.BLUE + '[CLOSE]',
              Style.RESET_ALL + msg)
    else:
        print(Fore.RED + 'ERROR: header is an invalid value.'
              + Style.RESET_ALL)

browser_app.py

`browser_app.py`


import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWebEngineWidgets import QWebEngineView as QWebView


class Ui_dialog(object):
    def setupUi(self, dialog, html_source):
        dialog.setObjectName('dialog')
        dialog.resize(1000, 650)
        self.stackedWidget = QtWidgets.QStackedWidget(dialog)
        self.stackedWidget.setGeometry(QtCore.QRect(10, 50, 980, 590))
        self.stackedWidget.setObjectName('stackedWidget')
        self.page_1 = QtWidgets.QWidget()
        self.page_1.setObjectName('page_1')
        self.webView = QWebView(self.page_1)
        self.webView.setGeometry(QtCore.QRect(0, 0, 980, 590))
        self.webView.setObjectName('webView')
        self.stackedWidget.addWidget(self.page_1)
        self.page_2 = QtWidgets.QWidget()
        self.page_2.setObjectName('page_2')
        self.page_2_title = QtWidgets.QLabel(self.page_2)
        self.page_2_title.setGeometry(QtCore.QRect(370, 60, 240, 50))
        font = QtGui.QFont()
        font.setPointSize(24)
        self.page_2_title.setFont(font)
        self.page_2_title.setObjectName('page_2_title')
        self.page_2_label1 = QtWidgets.QLabel(self.page_2)
        self.page_2_label1.setGeometry(QtCore.QRect(435, 230, 110, 22))
        font = QtGui.QFont()
        font.setPointSize(16)
        self.page_2_label1.setFont(font)
        self.page_2_label1.setObjectName('page_2_label1')
        self.page_2_ip = QtWidgets.QLineEdit(self.page_2)
        self.page_2_ip.setGeometry(QtCore.QRect(435, 262, 110, 28))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.page_2_ip.setFont(font)
        self.page_2_ip.setObjectName('page_2_ip')
        self.page_2_label2 = QtWidgets.QLabel(self.page_2)
        self.page_2_label2.setGeometry(QtCore.QRect(468, 310, 42, 16))
        font = QtGui.QFont()
        font.setPointSize(16)
        self.page_2_label2.setFont(font)
        self.page_2_label2.setObjectName('page_2_label2')
        self.page_2_url = QtWidgets.QLineEdit(self.page_2)
        self.page_2_url.setGeometry(QtCore.QRect(335, 336, 310, 28))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.page_2_url.setFont(font)
        self.page_2_url.setObjectName('page_2_url')
        self.page_2_save = QtWidgets.QPushButton(self.page_2)
        self.page_2_save.setGeometry(QtCore.QRect(425, 384, 130, 40))
        font = QtGui.QFont()
        font.setPointSize(18)
        self.page_2_save.setFont(font)
        self.page_2_save.setObjectName('page_2_save')
        self.stackedWidget.addWidget(self.page_2)
        self.url_lineEdit = QtWidgets.QLineEdit(dialog)
        self.url_lineEdit.setGeometry(QtCore.QRect(10, 10, 666, 30))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.url_lineEdit.setFont(font)
        self.url_lineEdit.setObjectName('url_lineEdit')
        self.search_btn = QtWidgets.QPushButton(dialog)
        self.search_btn.setGeometry(QtCore.QRect(670, 10, 90, 30))
        font = QtGui.QFont()
        font.setPointSize(12)
        self.search_btn.setFont(font)
        self.search_btn.setCursor(QtGui.QCursor(QtCore.Qt.PointingHandCursor))
        self.search_btn.setObjectName('search_btn')
        self.config_btn = QtWidgets.QPushButton(dialog)
        self.config_btn.setGeometry(QtCore.QRect(780, 10, 60, 30))
        font = QtGui.QFont()
        font.setPointSize(10)
        self.config_btn.setFont(font)
        self.config_btn.setObjectName('config_btn')

        # ----------------------------------------------

        self.url_lineEdit.setText('in preparation')
        self.page_2_title.setText('Setting the DNS')
        self.page_2_label1.setText('IP Address')
        self.page_2_ip.setText('in preparation')
        self.page_2_label2.setText('URL')
        self.page_2_url.setText('in preparation')

        self.webView.setHtml(html_source)

        # ----------------------------------------------

        QtCore.QMetaObject.connectSlotsByName(dialog)


def mybrowser(html_source):
    app = QtWidgets.QApplication(sys.argv)
    dialog = QtWidgets.QDialog()
    ui = Ui_dialog()
    ui.setupUi(dialog, html_source)
    dialog.show()
    sys.exit(app.exec_())

HTTP server and HTTP client using Socket (+ web browser) --Python3

HTTP communication using Socket module

Start-line and header-section

About the start line start-line

About header section header-section

Server side

Client side

Implementation so far

Client side request line + header clause

Server-side status line + header clause

The function make_status_line ()-> status line returns:

The function make_header_section (Content-Length value)-> header section returns:

The function read_index_html ()-> the contents of index.html, the length of index.html returns:

Information that the server needs to retrieve from the request

Message-body

Client side

Server side

Implementation of socket communication

Server side

Client side

Extract data

Client side

Server side

Display the obtained html like a browser

browser_app.py

Source code

client.py

server.py

colored_print.py

browser_app.py

The function `make_status_line ()-> status line` returns:

The function `make_header_section (Content-Length value)-> header section` returns:

The function `read_index_html ()-> the contents of index.html, the length of index.html` returns:

`browser_app.py`

`client.py`

`server.py`

`colored_print.py`

`browser_app.py`