generalize bootleg throttle thing

ttadmin/common/forms.py

@@ -1,3 +1,4 @@
+from datetime import datetime, timedelta
 from random import shuffle
 
 from django.core.exceptions import ValidationError
@@ -17,9 +18,26 @@ def validate_captcha(captcha):
     if captcha != NOT_A_ROBOT:
         raise ValidationError('Are you sure you are not a robot?')
 
+
 class CaptchaField(ChoiceField):
     def __init__(self):
         super().__init__(choices=CAPTCHA_CHOICES,
                          label='are you a robot?',
                          help_text='pick the response that indicates whether or not you are a robot.',
                          validators=(validate_captcha,))
+
+
+# this should go in something like redis. I refuse, however, to involve redis
+# in all of this until i have 2-3 more usecases.
+def throttler(cache):
+    def throttle(key):
+        nonlocal cache
+        last_submission = cache.get(key)
+        now = datetime.now()
+        if last_submission is None\
+           or now - last_submission > timedelta(minutes=30):
+            cache[key] = now
+        else:
+            raise ValidationError('you have submitted pretty recently. try again in a bit.')
+
+    return throttle

ttadmin/common/throttling.py

@@ -0,0 +1,14 @@
+from datetime import datetime, timedelta
+from django.core.exceptions import ValidationError
+
+def throttler(cache):
+    def throttle(key):
+        nonlocal cache
+        last_submission = cache.get(key)
+        if last_submission is None\
+           or now - last_submission > timedelta(minutes=30):
+            cache[key] = now
+        else:
+            raise ValidationError('you have submitted pretty recently. try again in a bit.')
+
+    return throttle

ttadmin/guestbook/forms.py

@@ -3,22 +3,12 @@ from datetime import datetime, timedelta
 from django.core.exceptions import ValidationError
 from django.forms import Form, CharField, EmailField, Textarea, ChoiceField
 
-from common.forms import CaptchaField
+from common.forms import CaptchaField, throttler
 
 
-# this should go in something like redis. I refuse, however, to involve redis
-# in all of this until i have 2-3 more usecases.
-# TODO generalize
 submission_throttle = {}
+throttle_submission = throttler(submission_throttle)
 
-def throttle_submission(name):
-    last_submission = submission_throttle.get(name)
-    now = datetime.now()
-    if last_submission is None\
-       or now - last_submission > timedelta(minutes=30):
-        submission_throttle[name] = datetime.now()
-    else:
-        raise ValidationError('you have submitted pretty recently. try again in a bit.')
 
 def validate_msg_text(msg):
     if len(msg) == 0:

ttadmin/help/forms.py

@@ -3,22 +3,13 @@ from datetime import datetime, timedelta
 from django.core.exceptions import ValidationError
 from django.forms import Form, CharField, EmailField, Textarea, ChoiceField
 
-from common.forms import CaptchaField
+from common.forms import CaptchaField, throttler
 from .models import ISSUE_TYPE_CHOICES
 
 
-# this should go in something like redis. I refuse, however, to involve redis
-# in all of this until i have 2-3 more usecases.
 submission_throttle = {}
+throttle_submission = throttler(submission_throttle)
 
-def throttle_submission(email):
-    last_submission = submission_throttle.get(email)
-    now = datetime.now()
-    if last_submission is None\
-       or now - last_submission > timedelta(minutes=30):
-        submission_throttle[email] = datetime.now()
-    else:
-        raise ValidationError('you have submitted pretty recently. try again in a bit.')
 
 def validate_issue_text(text):
     if len(text) == 0: