Put span.attributes to AzureMonitor properties (#682)

Author: reyang

contrib/opencensus-ext-azure/CHANGELOG.md

@@ -1,6 +1,8 @@
 # Changelog
 
 ## Unreleased
+- Support span attributes
+  ([#682](https://github.com/census-instrumentation/opencensus-python/pull/682))
 
 ## 0.2.0
 Released 2019-05-31

contrib/opencensus-ext-azure/opencensus/ext/azure/trace_exporter/__init__.py

@@ -71,6 +71,7 @@ def span_data_to_envelope(self, sd):
                 ),
                 responseCode='0',  # TODO
                 success=True,  # TODO
+                properties={},
             )
             envelope.data = Data(baseData=data, baseType='RequestData')
             if 'http.method' in sd.attributes:
@@ -92,6 +93,7 @@ def span_data_to_envelope(self, sd):
                     sd.end_time,
                 ),
                 success=True,  # TODO
+                properties={},
             )
             envelope.data = Data(
                 baseData=data,
@@ -107,7 +109,9 @@ def span_data_to_envelope(self, sd):
                     data.resultCode = str(sd.attributes['http.status_code'])
             else:
                 data.type = 'INPROC'
-        # TODO: links, tracestate, tags, attrs
+        # TODO: links, tracestate, tags
+        for key in sd.attributes:
+            data.properties[key] = sd.attributes[key]
         return envelope
 
     def emit(self, batch, event=None):