ch8 live code

064fd848 · James R. Wilcox · eef3655d · 064fd848 · 064fd848 · 064fd848
Commit 064fd848 authored 2 years ago by James R. Wilcox
--- a/ch8/browser.py
+++ b/ch8/browser.py
@@ -5,6 +5,7 @@ import tkinter.font
 import socket
 import ssl
 import sys
+import urllib.parse

 from typing import Dict, List, Literal, Optional, Union

@@ -112,7 +113,36 @@ class Tab:
                self.focus = elt
                elt.attributes["value"] = ""
                return self.render()
-            elt = elt.parent
+            elif elt.tag == "button":
+                # elt is the button we clicked
+                while elt:
+                    if elt.tag == "form" and "action" in elt.attributes:
+                        self.submit_form(elt)
+                    elt = elt.parent
+            if elt is not None:
+                elt = elt.parent
+
+    # elt is the node of the <form> tag
+    def submit_form(self, elt):
+        # find all <input> tags that are descendents of elt
+        inputs = [node for node in tree_to_list(elt, [])
+                  if isinstance(node, Element)
+                  and node.tag == "input"
+                  and "name" in node.attributes]
+        # form encode the key-value pairs
+        body = ""
+        for input in inputs:
+            name = input.attributes["name"]
+            value = input.attributes.get("value", "")
+            name = urllib.parse.quote(name)
+            value = urllib.parse.quote(value)
+            body += "&" + name + "=" + value
+        body = body[1:]
+
+        url = elt.attributes["action"]
+        url = resolve_url(url, self.url)
+
+        headers, body = request(url, body)

    def scrolldown(self):
        max_y = max(self.document.height - (HEIGHT - CHROME_PX), 0)
@@ -275,8 +305,9 @@ class Browser:
        self.tabs.append(new_tab)
        self.draw()

-
-def request(url):
+# if payload == None, then send a GET request
+# otherwise, send a POST request with the payload as the body
+def request(url, payload=None):
    scheme, url = url.split("://", 1)
    assert scheme in ["http", "https"], f"Unknown scheme: {scheme}"

@@ -301,8 +332,18 @@ def request(url):

    s.connect((host, port))

-    s.send(bytes(f"GET {path} HTTP/1.0\r\n", encoding="utf8") +
-           bytes(f"Host: {host}\r\n\r\n", encoding="utf8"))
+    method = "POST" if payload is not None else "GET"
+
+    body = (f"{method} {path} HTTP/1.0\r\n" +
+            f"Host: {host}\r\n")
+
+    if payload is not None:
+        length = len(payload.encode("utf8"))
+        body += f"Content-Length: {length}\r\n"
+
+    body += "\r\n" + (payload or "")
+
+    s.send(body.encode("utf8"))

    response = s.makefile("r", encoding="utf8", newline="\r\n")
    statusline = response.readline()

--- a/ch8/server.py
+++ b/ch8/server.py
+import socket
+
+
+counter = 0
+
+def do_request(method, url, headers, body):
+    print(method, url, headers, body)
+
+    global counter
+    counter += 1
+    return "200 OK", f"<html>hello you are the lucky {counter}th visitor</html>"
+
+def handle_connection(conx):
+    req = conx.makefile("b")
+    reqline = req.readline().decode("utf8")
+    method, url, version = reqline.split(" ", 2)
+
+    assert method in ["GET", "POST"]
+
+    headers = {}
+    for line in req:
+        line = line.decode('utf8')
+        if line == '\r\n': break
+        header, value = line.split(":", 1)
+        headers[header.lower()] = value.strip()
+
+    print(method, url, version, headers)
+
+    if 'content-length' in headers:
+        length = int(headers['content-length'])
+        body = req.read(length).decode('utf8')
+    else:
+        body = None
+
+    status, body = do_request(method, url, headers, body)
+    response = "HTTP/1.0 {}\r\n".format(status)
+    response += "Content-Length: {}\r\n".format(
+        len(body.encode("utf8")))
+    response += "\r\n" + body
+    conx.send(response.encode('utf8'))
+    conx.close()
+
+if __name__ == "__main__":
+    s = socket.socket(
+        family=socket.AF_INET,
+        type=socket.SOCK_STREAM,
+        proto=socket.IPPROTO_TCP,
+    )
+    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+
+    s.bind(('', 8000))
+    s.listen()
+
+    while True:
+        conx, addr = s.accept()
+        handle_connection(conx)
--- a/ch8/test.html
+++ b/ch8/test.html
 <html>
  <body>
    <form action="/submit" method="post">
-    <p>Name: <input name=name value=1></p>
-    <p>Comment: <input name=comment value=2></p>
-    <p><button>Submit!</button></p>
+      <p>Name: <input name=name value=1></p>
+      <p>Comment: <input name=comment value=2></p>
+      <p><button>Submit!</button></p>
    </form>
  </body>
 </html>