Add a context manager object and a method to call said object

rollbar/__init__.py

@@ -536,6 +536,23 @@ def wait(f=None):
         return f()
 
 
+def watch(key, extra_data=None):
+    """
+    Sets the scope for the code wrapped by this method.
+
+    key: key for the current scope.
+    extra_data: optional, will be included in the root level of the 'scope' object. If not
+                a dict, the value can be found under the 'extra' key in the 'scope' object.
+                The keyword 'key' is reserved.
+
+    Usage:
+
+        with Rollbar.watch('foobar'):
+            do_something_risky()
+    """
+    return _BigBrother(key, extra_data)
+
+
 class ApiException(Exception):
     """
     This exception will be raised if there was a problem decoding the
@@ -702,6 +719,12 @@ def _report_exc_info(exc_info, request, extra_data, payload_data, level=None):
     if extra_trace_data and not extra_data:
         data['custom'] = extra_trace_data
 
+    if scopes:
+        data['scope'] = scopes[-1]
+
+        global scopes
+        scopes = []
+
     request = _get_actual_request(request)
     _add_request_data(data, request)
     _add_person_data(data, request)
@@ -787,6 +810,9 @@ def _report_message(message, level, request, extra_data, payload_data):
     _add_person_data(data, request)
     _add_lambda_context_data(data)
     data['server'] = _build_server_data()
+
+    if scopes:
+        data['scope'] = scopes[-1]
 
     if payload_data:
         data = dict_merge(data, payload_data, silence_errors=True)
@@ -1606,3 +1632,34 @@ def _wsgi_extract_user_ip(environ):
     if real_ip:
         return real_ip
     return environ['REMOTE_ADDR']
+
+
+scopes = []
+
+
+class _BigBrother(object):
+    """
+    Context manager object that interfaces with the `scopes` stack:
+
+        On enter, puts current scope object on top of stack.
+        On exit and there is no exception, pops off top element from stack.
+    """
+    def __init__(self, key, extra_data):
+        scope = {'key': key}
+
+        if extra_data:
+            if not isinstance(extra_data, dict):
+                extra_data = {'extra': extra_data}
+
+            extra_data.update(scope)
+            scope = extra_data
+
+        self.scope = scope
+
+    def __enter__(self):
+        scopes.append(self.scope)
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        if not exc_type:
+            scopes.pop()