Add ability to trace SQL transactions with profiler

Closes-Bug: #2082944
Change-Id: I8781359e338ffb44e5f55211bec147000a2097cb

manila/db/sqlalchemy/api.py

@@ -41,6 +41,7 @@ from oslo_utils import importutils
 from oslo_utils import strutils
 from oslo_utils import timeutils
 from oslo_utils import uuidutils
+import sqlalchemy as sa
 from sqlalchemy import and_
 from sqlalchemy import MetaData
 from sqlalchemy import or_
@@ -77,6 +78,14 @@ context_manager = enginefacade.transaction_context()
 
 context_manager.configure()
 
+if (
+    osprofiler_sqlalchemy and
+    CONF.profiler.enabled and
+    CONF.profiler.trace_sqlalchemy
+):
+    context_manager.append_on_engine_create(
+        lambda engine: osprofiler_sqlalchemy.add_tracing(sa, engine, "db"))
+
 
 def get_engine():
     return context_manager.writer.get_engine()

releasenotes/notes/bug-2082944-sqlalchemy-tracing.yml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Added tracing to SQLAlchemy engine if profiler is enabled and
+    profiler.trace_sqlalchemy is set to true.