I am writing simple web-site with js-client and a server side(python) I did everything to remove CORS error but nothing works. I wrote all needed headers for this but still get this error. So web-site should send a request to a server and get answer. Error:
Access to XMLHttpRequest at 'http://127.0.0.1:8000/' from origin 'null' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
myFile.html:
<!DOCTYPE html>
<html>
<head>
<title>requestJs</title>
</head>
<body>
<button class="myButton">SEND</button>
<script type="text/javascript">
let theButton = document.querySelector(".myButton");
theButton.addEventListener('click',function() {
const xhr = new XMLHttpRequest();
xhr.onload = function() {
alert(`Статус: ${xhr.status}; Результат: ${xhr.response}`)
};
xhr.onerror = function() {
alert('Ошибка запроса');
};
xhr.open("GET", "http://127.0.0.1:8000/", true);
xhr.send(2);
})
</script>
</body>
</html>
Server side:
import http.server as httpserver
class CORSHTTPRequestHandler(httpserver.SimpleHTTPRequestHandler):
def send_head(self):
"""Common code for GET and HEAD commands.
This sends the response code and MIME headers.
Return value is either a file object (which has to be copied
to the outputfile by the caller unless the command was HEAD,
and must be closed by the caller under all circumstances), or
None, in which case the caller has nothing further to do.
"""
path = self.translate_path(self.path)
f = None
if os.path.isdir(path):
if not self.path.endswith('/'):
# redirect browser - doing basically what apache does
self.send_response(301)
self.send_header("Location", self.path + "/")
self.end_headers()
return None
for index in "index.html", "index.html":
index = os.path.join(path, index)
if os.path.exists(index):
path = index
break
else:
return self.list_directory(path)
ctype = self.guess_type(path)
try:
# Always read in binary mode. Opening files in text mode may cause
# newline translations, making the actual size of the content
# transmitted *less* than the content-length!
f = open(path, 'rb')
except IOError:
self.send_error(404, "File not found")
return None
self.send_response(200)
self.send_header("Content-type", ctype)
fs = os.fstat(f.fileno())
self.send_header("Content-Length", str(fs[6]))
self.send_header("Last-Modified", self.date_time_string(fs.st_mtime))
self.send_header("Access-Control-Allow-Origin:", "*")
self.send_header("Access-Control-Allow-Methods:", "GET,HEAD,PUT,PATCH,POST,DELETE")
self.send_header("Access-Control-Allow-Headers:", "Content-Type, Access-Control-Allow-Origin, xxx")
self.end_headers()
return f
if __name__ == "__main__":
import os
import socketserver
import sys
PORT = int(sys.argv[1]) if len(sys.argv) > 1 else 8000
handler = CORSHTTPRequestHandler
httpd = socketserver.TCPServer(("", PORT), handler)
print(f"serving at port {PORT}")
httpd.serve_forever()
Help me please, what is my problem?
