WIP Deprecation log bwc test

qa/rolling-upgrade/build.gradle

@@ -86,6 +86,7 @@ for (Version version : bwcVersions.wireCompatible) {
       dataDir = { nodeNumber -> oldClusterTest.nodes[stopNode].dataDir }
       setting 'repositories.url.allowed_urls', 'http://snapshot.test*'
       setting 'node.name', "upgraded-node-${stopNode}"
+      setting 'node.attr.gen', "upgraded"
       setting 'logger.level', 'DEBUG'
     }
   }

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/mixed_cluster/20_joda.yml

@@ -0,0 +1,54 @@
+---
+"Index to old node":
+  - skip:
+      features: ["node_selector","warnings"]
+  - do:
+      node_selector:
+        attribute:
+          gen: "old"
+      bulk:
+        refresh: true
+        body:
+          - '{"index": {"_index": "jodaindex", "_type": "doc", "_id": "id_2"}}'
+          - '{"datefield": "2019-01-02T00:00+01:00"}'
+
+  - do:
+      indices.flush:
+        index: jodaindex
+
+  - do:
+      node_selector:
+        attribute:
+          gen: "old"
+      warnings:
+        - 'There are doc-value fields which are not using a format. The output will change in 7.0 when doc value fields get formatted based on mappings by default. It is recommended to pass [format=use_field_mapping] with a doc value field in order to opt in for the future behaviour and ease the migration to 7.0: [count]'
+      search:
+        index: jodaindex
+        body:
+          sort: datefield
+          docvalue_fields: [ "count"]
+  - match: { hits.total: 2 }
+  - match: { hits.hits.0._id: id_1 }
+  - match: { hits.hits.1._id: id_2 }
+  - match: { _shards.failed: 0 }
+
+
+
+---
+"Search index with joda format that generates a warning":
+  - skip:
+      features: "node_selector"
+  - do:
+      node_selector:
+        attribute:
+          gen: "upgraded"
+      search:
+        index: jodaindex
+        body:
+          sort: datefield
+          docvalue_fields: [ "count"]
+  - match: { hits.total: 2 }
+  - match: { hits.hits.0._id: id_1 }
+  - match: { hits.hits.1._id: id_2 }
+  - match: { _shards.failed: 0 }
+

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/old_cluster/20_joda.yml

@@ -0,0 +1,33 @@
+---
+"Create index with joda format that generates a warning":
+  - skip:
+      features: "warnings"
+      version: "6.7.1 - "
+      reason: date from warning wars removed in 6.7
+  - do:
+      indices.create:
+        index: jodaindex
+        body:
+          mappings:
+            "doc":
+              "properties":
+                "datefield":
+                  "type": "date"
+                  "format": "YYYY-MM-dd'T'HH:mmZZ"
+
+  - do:
+      bulk:
+        refresh: true
+        body:
+          - '{"index": {"_index": "jodaindex", "_type": "doc", "_id": "id_1"}}'
+          - '{"datefield": "2019-01-02T00:00+01:00"}'
+
+  - do:
+      search:
+        index: jodaindex
+        body:
+          query:
+            range:
+              datefield:
+                gte: "2019-01-01T00:00+01:00"
+  - match: { hits.total: 1 }

qa/rolling-upgrade/src/test/resources/rest-api-spec/test/upgraded_cluster/20_joda.yml

@@ -0,0 +1,14 @@
+---
+"Search index with joda format that generates a warning":
+  - skip:
+      features: "warnings"
+  - do:
+      search:
+        rest_total_hits_as_int: true
+        index: jodaindex*
+        body:
+          query:
+            range:
+              datefield:
+                gte: "2019-01-01T00:00+01:00"
+  - match: { hits.total: 5 }

server/src/main/java/org/elasticsearch/common/util/concurrent/ThreadContext.java

@@ -489,6 +489,7 @@ private void putSingleHeader(String key, String value, Map<String, String> newHe
             }
         }
 
+
         private ThreadContextStruct putHeaders(Map<String, String> headers) {
             if (headers.isEmpty()) {
                 return this;