Add sample_rate configuration

Author: dcramer

docs/advanced.rst

@@ -175,6 +175,16 @@ The following are valid arguments which may be passed to the Raven client:
     String declaration is strict (ie. does not works for child exceptions)
     whereas class declaration handle inheritance (ie. child exceptions are also ignored).
 
+.. describe:: sample_rate
+
+    The sampling factor to apply to events. A value of 0.00 will deny sending
+    any events, and a value of 1.00 will send 100% of events.
+
+    .. code-block:: python
+
+        # send 50% of events
+        sample_rate = 5.0
+
 .. describe:: list_max_length
 
     The maximum number of items a list-like container should store.

raven/base.py

@@ -18,6 +18,7 @@
 
 from datetime import datetime
 from inspect import isclass
+from random import Random
 from types import FunctionType
 from threading import local
 
@@ -150,7 +151,8 @@ class Client(object):
 
     def __init__(self, dsn=None, raise_send_errors=False, transport=None,
                  install_sys_hook=True, install_logging_hook=True,
-                 hook_libraries=None, enable_breadcrumbs=True, **options):
+                 hook_libraries=None, enable_breadcrumbs=True,
+                 _random_seed=None, **options):
         global Raven
 
         o = options
@@ -195,12 +197,14 @@ def __init__(self, dsn=None, raise_send_errors=False, transport=None,
         self.environment = o.get('environment') or None
         self.release = o.get('release') or os.environ.get('HEROKU_SLUG_COMMIT')
         self.repos = self._format_repos(o.get('repos'))
+        self.sample_rate = o.get('sample_rate') or 1
         self.transaction = TransactionStack()
-
         self.ignore_exceptions = set(o.get('ignore_exceptions') or ())
 
         self.module_cache = ModuleProxyCache()
 
+        self._random = Random(_random_seed)
+
         if not self.is_enabled():
             self.logger.info(
                 'Raven is not configured (logging is disabled). Please see the'
@@ -627,7 +631,9 @@ def capture(self, event_type, data=None, date=None, time_spent=None,
             event_type, data, date, time_spent, extra, stack, tags=tags,
             **kwargs)
 
-        self.send(**data)
+        # should this event be sampled?
+        if self._random.random() <= self.sample_rate:
+            self.send(**data)
 
         self._local_state.last_event_id = data['event_id']
 

raven/utils/conf.py

@@ -53,6 +53,7 @@ def getopt(key, default=None):
     options.setdefault('repos', getopt('repos'))
     options.setdefault('environment', getopt('environment'))
     options.setdefault('ignore_exceptions', getopt('ignore_exceptions'))
+    options.setdefault('sample_rate', getopt('sample_rate'))
 
     transport = getopt('transport') or options.get('transport')
     if isinstance(transport, string_types):