mail ready

2026-09-27 18:30:34 +02:00
parent 774c601889
commit fb995cefdb
33 changed files with 2787 additions and 193 deletions
@@ -0,0 +1,132 @@
+"""Small WSGI contact endpoint. Run behind HTTPS and the Nginx rate limit."""
+import base64
+import binascii
+import hashlib
+import hmac
+import json
+import logging
+import os
+import re
+import secrets
+import time
+import urllib.error
+import urllib.parse
+import urllib.request
+
+LOG = logging.getLogger(__name__)
+ORIGIN = os.environ.get('CONTACT_ORIGIN', 'https://dilibworld.com').rstrip('/')
+SECRET = os.environ.get('CONTACT_FORM_SECRET', '').encode()
+SENDER = os.environ.get('GRAPH_SENDER', 'info@dilibworld.com')
+RECIPIENT = os.environ.get('CONTACT_RECIPIENT', 'info@dilibworld.com')
+FIELDS = {
+    'de': ('Vorname', 'Nachname', 'Unternehmen', 'E-Mail', 'Telefon', 'Thema', 'Nachricht'),
+    'en': ('First name', 'Last name', 'Company', 'Email', 'Phone', 'Topic', 'Message'),
+}
+USED = {}
+
+
+def reply(start_response, status, data):
+    body = json.dumps(data).encode()
+    start_response(status, [('Content-Type', 'application/json; charset=utf-8'),
+                            ('Content-Length', str(len(body))), ('Cache-Control', 'no-store'),
+                            ('X-Content-Type-Options', 'nosniff')])
+    return [body]
+
+
+def token():
+    value = f'{int(time.time())}:{secrets.token_urlsafe(18)}'
+    signature = hmac.new(SECRET, value.encode(), hashlib.sha256).hexdigest()
+    return base64.urlsafe_b64encode(f'{value}:{signature}'.encode()).decode()
+
+
+def valid_token(value):
+    try:
+        raw = base64.urlsafe_b64decode(value.encode()).decode()
+        timestamp, nonce, signature = raw.split(':')
+        signed = f'{timestamp}:{nonce}'
+        age = time.time() - int(timestamp)
+        digest = hmac.new(SECRET, signed.encode(), hashlib.sha256).hexdigest()
+        if not (3 <= age <= 3600 and hmac.compare_digest(digest, signature)):
+            return False
+        now = time.time()
+        for key, expiry in list(USED.items()):
+            if expiry < now:
+                del USED[key]
+        if signature in USED:
+            return False
+        USED[signature] = now + 3600
+        return True
+    except (ValueError, UnicodeError, TypeError, binascii.Error):
+        return False
+
+
+def graph_send(values, lang):
+    tenant = os.environ['GRAPH_TENANT_ID']
+    app_id = os.environ['GRAPH_CLIENT_ID']
+    client_secret = os.environ['GRAPH_CLIENT_SECRET']
+    form = urllib.parse.urlencode({'client_id': app_id, 'client_secret': client_secret,
+                                   'scope': 'https://graph.microsoft.com/.default',
+                                   'grant_type': 'client_credentials'}).encode()
+    url = f'https://login.microsoftonline.com/{urllib.parse.quote(tenant, safe="")}/oauth2/v2.0/token'
+    request = urllib.request.Request(url, form, {'Content-Type': 'application/x-www-form-urlencoded'})
+    with urllib.request.urlopen(request, timeout=10) as response:
+        access_token = json.load(response)['access_token']
+    labels = FIELDS[lang]
+    content = '\n'.join(f'{label}: {values.get(label, "")}' for label in labels)
+    email = values[labels[3]]
+    message = {'message': {
+        'subject': 'Kontaktanfrage über dilibworld.com',
+        'body': {'contentType': 'Text', 'content': content},
+        'toRecipients': [{'emailAddress': {'address': RECIPIENT}}],
+        'replyTo': [{'emailAddress': {'address': email}}],
+    }, 'saveToSentItems': True}
+    endpoint = 'https://graph.microsoft.com/v1.0/users/' + urllib.parse.quote(SENDER, safe='@') + '/sendMail'
+    request = urllib.request.Request(endpoint, json.dumps(message).encode(),
+                                     {'Content-Type': 'application/json', 'Authorization': f'Bearer {access_token}'})
+    with urllib.request.urlopen(request, timeout=15) as response:
+        if response.status != 202:
+            raise RuntimeError('Graph did not accept the message')
+
+
+def application(environ, start_response):
+    if environ.get('PATH_INFO') != '/api/contact':
+        return reply(start_response, '404 Not Found', {'error': 'not_found'})
+    if not SECRET or not all(os.environ.get(key) for key in ('GRAPH_TENANT_ID', 'GRAPH_CLIENT_ID', 'GRAPH_CLIENT_SECRET')):
+        LOG.error('Contact service configuration incomplete')
+        return reply(start_response, '503 Service Unavailable', {'error': 'unavailable'})
+    method = environ.get('REQUEST_METHOD')
+    if method == 'GET':
+        return reply(start_response, '200 OK', {'token': token()})
+    if method != 'POST':
+        return reply(start_response, '405 Method Not Allowed', {'error': 'method'})
+    if environ.get('HTTP_ORIGIN') != ORIGIN or environ.get('CONTENT_TYPE', '').split(';')[0] != 'application/json':
+        return reply(start_response, '403 Forbidden', {'error': 'origin'})
+    try:
+        length = int(environ.get('CONTENT_LENGTH', '0'))
+        if not 0 < length <= 12000:
+            raise ValueError('length')
+        data = json.loads(environ['wsgi.input'].read(length))
+        lang = data.get('lang')
+        if lang not in FIELDS or not isinstance(data.get('website'), str) or not isinstance(data.get('token'), str):
+            raise ValueError('fields')
+        if data['website']:
+            return reply(start_response, '200 OK', {'ok': True})
+        if not valid_token(data['token']):
+            raise ValueError('token')
+        labels = FIELDS[lang]
+        values = {key: data.get(key, '') for key in labels}
+        if any(not isinstance(v, str) or len(v) > (5000 if key == labels[6] else 200) for key, v in values.items()):
+            raise ValueError('field length')
+        if not all(values[key].strip() for key in (labels[0], labels[1], labels[3], labels[6])):
+            raise ValueError('required')
+        if not re.fullmatch(r'[^\s@\r\n]+@[^\s@\r\n]+\.[^\s@\r\n]+', values[labels[3]]) or len(values[labels[3]]) > 254:
+            raise ValueError('email')
+        if data.get('privacy') not in ('akzeptiert', 'accepted'):
+            raise ValueError('privacy')
+        graph_send(values, lang)
+    except (ValueError, TypeError, KeyError, json.JSONDecodeError):
+        return reply(start_response, '400 Bad Request', {'error': 'invalid'})
+    except (urllib.error.URLError, TimeoutError, RuntimeError):
+        LOG.exception('Contact delivery failed')
+        return reply(start_response, '502 Bad Gateway', {'error': 'delivery'})
+    return reply(start_response, '200 OK', {'ok': True})