logging: Vendor findCaller for correct stack frame info in logs

common/logging_extra.py

@@ -118,6 +118,42 @@ class SwagLogger(logging.Logger):
     else:
       self.info(evt)
 
+  def findCaller(self, stack_info=False, stacklevel=1):
+    """
+    Find the stack frame of the caller so that we can note the source
+    file name, line number and function name.
+    """
+    f = sys._getframe(3)
+    #On some versions of IronPython, currentframe() returns None if
+    #IronPython isn't run with -X:Frames.
+    if f is not None:
+        f = f.f_back
+    orig_f = f
+    while f and stacklevel > 1:
+        f = f.f_back
+        stacklevel -= 1
+    if not f:
+        f = orig_f
+    rv = "(unknown file)", 0, "(unknown function)", None
+    while hasattr(f, "f_code"):
+        co = f.f_code
+        filename = os.path.normcase(co.co_filename)
+        if filename == _srcfile:
+            f = f.f_back
+            continue
+        sinfo = None
+        if stack_info:
+            sio = io.StringIO()
+            sio.write('Stack (most recent call last):\n')
+            traceback.print_stack(f, file=sio)
+            sinfo = sio.getvalue()
+            if sinfo[-1] == '\n':
+                sinfo = sinfo[:-1]
+            sio.close()
+        rv = (co.co_filename, f.f_lineno, co.co_name, sinfo)
+        break
+    return rv
+
 if __name__ == "__main__":
   log = SwagLogger()