Marker Check for Auto HTTP Monkey PAtching

The monkey patching assumes a marker is present but this may not always
be the case. For example, if the profiler plugin is loaded after the
trace plugin, then the profiler won't be provided an active marker. This
removes marker removal and makes the monkey patching defensive about the
presence of markers.

iopipe/contrib/trace/auto_http.py

@@ -70,6 +70,8 @@ def patch_requests_session_send(context, http_filter, http_headers):
         return
 
     def send(self, *args, **kwargs):
+        if not hasattr(context, "iopipe") or not hasattr(context.iopipe, "mark"):
+            return original_requests_session_send(self, *args, **kwargs)
         id = ensure_utf8(str(uuid.uuid4()))
         with context.iopipe.mark(id):
             response = original_requests_session_send(self, *args, **kwargs)
@@ -96,6 +98,8 @@ def patch_botocore_session_send(context, http_filter, http_headers):
         return
 
     def send(self, *args, **kwargs):
+        if not hasattr(context, "iopipe") or not hasattr(context.iopipe, "mark"):
+            return original_botocore_session_send(self, *args, **kwargs)
         id = str(uuid.uuid4())
         with context.iopipe.mark(id):
             response = original_botocore_session_send(self, *args, **kwargs)
@@ -122,6 +126,8 @@ def patch_botocore_vendored_session_send(context, http_filter, http_headers):
         return
 
     def send(self, *args, **kwargs):
+        if not hasattr(context, "iopipe") or not hasattr(context.iopipe, "mark"):
+            return original_botocore_vendored_session_send(self, *args, **kwargs)
         id = str(uuid.uuid4())
         with context.iopipe.mark(id):
             response = original_botocore_vendored_session_send(self, *args, **kwargs)

iopipe/contrib/trace/plugin.py

@@ -49,14 +49,12 @@ def post_setup(self, iopipe):
 
     def pre_invoke(self, event, context):
         self.timeline = Timeline()
-        context.iopipe.register("mark", Marker(self.timeline, context))
+        context.iopipe.register("mark", Marker(self.timeline, context), force=True)
 
         if self.auto_http is True:
             patch_http_requests(context, self.http_filter, self.http_headers)
 
     def post_invoke(self, event, context):
-        context.iopipe.unregister("mark")
-
         if self.auto_http is True:
             restore_http_requests()