config, bot: Configurable message rate

sopel/bot.py

@@ -307,18 +307,28 @@ def say(self, text, recipient, max_messages=1):
 
             recipient_id = Identifier(recipient)
 
-            if recipient_id not in self.stack:
-                self.stack[recipient_id] = []
-            elif self.stack[recipient_id]:
-                elapsed = time.time() - self.stack[recipient_id][-1][0]
-                if elapsed < 3:
-                    penalty = float(max(0, len(text) - 40)) / 70
-                    wait = 0.8 + penalty
-                    if elapsed < wait:
-                        time.sleep(wait - elapsed)
+            reciprec = self.stack.get(recipient_id)
+            if not reciprec:
+                reciprec = self.stack[recipient_id] = {
+                    'messages': [],
+                    'burst': self.config.core.bucket_burst_tokens,
+                }
+
+            if not reciprec['burst']:
+                elapsed = time.time() - reciprec['messages'][-1][0]
+                reciprec['burst'] = min(
+                    self.config.core.bucket_burst_tokens,
+                    int(elapsed) * self.config.core.bucket_refill_rate)
+
+            if not reciprec['burst']:
+                elapsed = time.time() - reciprec['messages'][-1][0]
+                penalty = float(max(0, len(text) - 50)) / 70
+                wait = self.config.core.bucket_empty_wait + penalty
+                if elapsed < wait:
+                    time.sleep(wait - elapsed)
 
                 # Loop detection
-                messages = [m[1] for m in self.stack[recipient_id][-8:]]
+                messages = [m[1] for m in reciprec['messages'][-8:]]
 
                 # If what we about to send repeated at least 5 times in the
                 # last 2 minutes, replace with '...'
@@ -329,8 +339,9 @@ def say(self, text, recipient, max_messages=1):
                         return
 
             self.write(('PRIVMSG', recipient), text)
-            self.stack[recipient_id].append((time.time(), self.safe(text)))
-            self.stack[recipient_id] = self.stack[recipient_id][-10:]
+            reciprec['burst'] = max(0, reciprec['burst'] - 1)
+            reciprec['messages'].append((time.time(), self.safe(text)))
+            reciprec['messages'] = reciprec['messages'][-10:]
         finally:
             self.sending.release()
         # Now that we've sent the first part, we need to send the rest. Doing

sopel/config/core_section.py

@@ -216,3 +216,16 @@ def homedir(self):
 
     verify_ssl = ValidatedAttribute('verify_ssl', bool, default=True)
     """Whether to require a trusted SSL certificate for SSL connections."""
+
+    bucket_burst_tokens = ValidatedAttribute('bucket_burst_tokens', int,
+                                             default=4)
+    """How many messages can be sent in burst mode."""
+
+    bucket_refill_rate = ValidatedAttribute('bucket_refill_rate', int,
+                                            default=1)
+    """How many tokens/second to add to the token bucket."""
+
+    bucket_empty_wait = ValidatedAttribute('bucket_empty_wait', float,
+                                           default=0.7)
+    """How long to wait before sending a messaging when not in burst
+    mode."""