Added top level API to get current span (#1954)

* Added top level API to get current span

sentry_sdk/__init__.py

@@ -32,6 +32,7 @@
     "set_user",
     "set_level",
     "set_measurement",
+    "get_current_span",
 ]
 
 # Initialize the debug support after everything is loaded

sentry_sdk/api.py

@@ -53,6 +53,7 @@ def overload(x):
     "set_user",
     "set_level",
     "set_measurement",
+    "get_current_span",
 ]
 
 
@@ -228,3 +229,15 @@ def set_measurement(name, value, unit=""):
     transaction = Hub.current.scope.transaction
     if transaction is not None:
         transaction.set_measurement(name, value, unit)
+
+
+def get_current_span(hub=None):
+    # type: (Optional[Hub]) -> Optional[Span]
+    """
+    Returns the currently active span if there is one running, otherwise `None`
+    """
+    if hub is None:
+        hub = Hub.current
+
+    current_span = hub.scope.span
+    return current_span

tests/test_api.py

@@ -0,0 +1,39 @@
+import mock
+
+from sentry_sdk import (
+    configure_scope,
+    get_current_span,
+    start_transaction,
+)
+
+
+def test_get_current_span():
+    fake_hub = mock.MagicMock()
+    fake_hub.scope = mock.MagicMock()
+
+    fake_hub.scope.span = mock.MagicMock()
+    assert get_current_span(fake_hub) == fake_hub.scope.span
+
+    fake_hub.scope.span = None
+    assert get_current_span(fake_hub) is None
+
+
+def test_get_current_span_default_hub(sentry_init):
+    sentry_init()
+
+    assert get_current_span() is None
+
+    with configure_scope() as scope:
+        fake_span = mock.MagicMock()
+        scope.span = fake_span
+
+        assert get_current_span() == fake_span
+
+
+def test_get_current_span_default_hub_with_transaction(sentry_init):
+    sentry_init()
+
+    assert get_current_span() is None
+
+    with start_transaction() as new_transaction:
+        assert get_current_span() == new_transaction