Merge pull request #25 from signalfx/FEED-2131

Add conditional check for a dimension related to tracing only

Author: Mark Stumpf

README.rst

@@ -132,8 +132,6 @@ to SignalFx:
 +----------------------------------+----------------------------------+
 | Dimension                        | Description                      |
 +==================================+==================================+
-| aws_request_id                   | AWS Request ID                   |
-+----------------------------------+----------------------------------+
 | lambda_arn                       | ARN of the Lambda function       |
 |                                  | instance                         |
 +----------------------------------+----------------------------------+

signalfx_lambda/tracing.py

@@ -13,7 +13,7 @@ def call(*args, **kwargs):
 
         tracer = init_jaeger_tracer(context)
 
-        span_tags = utils.get_fields(context)
+        span_tags = utils.get_tracing_fields(context)
         span_tags['component'] = 'python-lambda-wrapper'
         span_tags[ext_tags.SPAN_KIND] = ext_tags.SPAN_KIND_RPC_SERVER
 

signalfx_lambda/utils.py

@@ -3,40 +3,46 @@
 
 from .version import name, version
 
-fields = {}
-
 def get_fields(context):
+    fields = {}
     function_arn = context.invoked_function_arn
 
+    # Expected format arn:aws:lambda:us-east-1:accountId:function:functionName:$LATEST
+    splitted = function_arn.split(':')
+    fields.update({
+        'aws_function_version': context.function_version,
+        'aws_function_name': context.function_name,
+        'aws_region': splitted[3],
+        'aws_account_id': splitted[4],
+        'function_wrapper_version': name + '_' + version
+    })
+
+    runtime_env = os.environ.get('AWS_EXECUTION_ENV')
+    if runtime_env is not None:
+        fields['aws_execution_env'] = runtime_env
+    if splitted[5] == 'function':
+        updatedArn = list(splitted)
+        if len(splitted) == 8:
+            fields['aws_function_qualifier'] = splitted[7]
+            updatedArn[7] = context.function_version
+        elif len(splitted) == 7:
+            updatedArn.append(context.function_version)
+        fields['lambda_arn'] = ':'.join(updatedArn)
+
+    elif splitted[5] == 'event-source-mappings':
+        fields['event_source_mappings'] = splitted[6]
+        fields['lambda_arn'] = function_arn
+
+    return fields
+
+def get_tracing_fields(context):
+    fields = get_fields(context)
     if fields.get('aws_request_id') != context.aws_request_id:
-        # Expected format arn:aws:lambda:us-east-1:accountId:function:functionName:$LATEST
-        splitted = function_arn.split(':')
-
         fields.update({
-            'aws_request_id': context.aws_request_id,
-            'aws_function_version': context.function_version,
-            'aws_function_name': context.function_name,
-            'aws_region': splitted[3],
-            'aws_account_id': splitted[4],
-            'function_wrapper_version': name + '_' + version
+            'aws_request_id': context.aws_request_id
         })
-        runtime_env = os.environ.get('AWS_EXECUTION_ENV')
-        if runtime_env is not None:
-            fields['aws_execution_env'] = runtime_env
-        if splitted[5] == 'function':
-            updatedArn = list(splitted)
-            if len(splitted) == 8:
-                fields['aws_function_qualifier'] = splitted[7]
-                updatedArn[7] = context.function_version
-            elif len(splitted) == 7:
-                updatedArn.append(context.function_version)
-            fields['lambda_arn'] = ':'.join(updatedArn)
-
-        elif splitted[5] == 'event-source-mappings':
-            fields['event_source_mappings'] = splitted[6]
-            fields['lambda_arn'] = function_arn
-
-    return fields.copy()
+
+    return fields
 
 
 def get_metrics_url():