Add tags field (apache#46)

Author: rainbend

common.graphqls

@@ -28,6 +28,12 @@ type Mutation {
     version: String
 }
 
+# String key, String value pair.
+type KeyValue {
+    key: String!
+    value: String
+}
+
 # The Duration defines the start and end time for each query operation.
 # Fields: `start` and `end`
 #   represents the time span. And each of them matches the step.

log.graphqls

@@ -34,6 +34,7 @@ type Log {
     statusCode: String
     contentType: ContentType!
     content: String
+    tags: [KeyValue!]
 }
 
 # Represent the conditions used for query logs

trace.graphqls

@@ -112,11 +112,6 @@ enum RefType {
     CROSS_THREAD
 }
 
-type KeyValue {
-    key: String!
-    value: String
-}
-
 type LogEntity {
     time: Long!
     data: [KeyValue!]