#!/usr/bin/python3
import cgi
import cgitb
import os
import subprocess
import urllib.request
cgitb.enable()
form = cgi.FieldStorage()
source = form.getvalue("source", None)
target = form.getvalue("target", None)
server = os.environ.get("SERVER_NAME", None)
method = os.environ.get("REQUEST_METHOD", "GET")
def validate(source, target, server, method):
status = 400
if method != "POST":
message = "Webmention MUST be performed through a POST request."
elif source is None or target is None:
message = "Please fill in the source and target fields."
elif "://" not in source or "://" not in target:
message = "Source and target fields should be URLs."
elif not target.split("://", 1)[1].startswith(server):
message = "Target should be a link to this domain: {0}".format(server)
elif target not in urllib.request.urlopen(source).read().decode("utf-8"):
message = "Source should have a link to the target: {0}".format(target)
else:
message = (
"Success! With source={source} and target={target}."
'Back to the target article.'
).format(
source=source,
target=target,
)
status = 202
return status, message, source, target
def send_response(callback, status, message, source, target):
print("Content-type: text/html")
print("Status: {0}".format(status))
print()
print(
"""
Webmention
{message}
""".format(
message=message
)
)
if status == 202:
callback(source, target)
def on_valid_submission(source, target):
commands = [
"cd /home/larlet/www",
"source /home/larlet/.virtualenvs/webmention/bin/activate",
"fab --hide=everything add_webmention:{source},{target}".format(
source=source,
target=target,
),
]
subprocess.call(" && ".join(commands), shell=True)
send_response(on_valid_submission, *validate(source, target, server, method))