Watcher: Fix chain input toXcontent serialization

x-pack/plugin/src/test/resources/rest-api-spec/test/watcher/get_watch/30_with_chain_input.yml

@@ -0,0 +1,51 @@
+---
+"Test get watch api with chained input and basic auth":
+  - do:
+      cluster.health:
+          wait_for_status: yellow
+
+  - do:
+      xpack.watcher.put_watch:
+        id: "my_watch"
+        body:  >
+          {
+            "trigger": {
+              "schedule": {
+                "cron": "0 0 0 1 * ? 2099"
+              }
+            },
+            "input": {
+              "chain": {
+                "inputs": [
+                  {
+                    "http": {
+                      "http": {
+                        "request": {
+                          "url" : "http://localhost/",
+                          "auth": {
+                            "basic": {
+                              "username": "Username123",
+                              "password": "Password123"
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                ]
+              }
+            },
+            "actions": {
+              "logging": {
+                "logging": {
+                  "text": "logging statement here"
+                }
+              }
+            }
+          }
+
+  - do:
+      xpack.watcher.get_watch:
+        id: "my_watch"
+  - match: { found : true}
+  - match: { _id: "my_watch" }

x-pack/plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/input/chain/ChainInput.java

@@ -41,7 +41,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         builder.startArray(INPUTS.getPreferredName());
         for (Tuple<String, Input> tuple : inputs) {
             builder.startObject().startObject(tuple.v1());
-            builder.field(tuple.v2().type(), tuple.v2());
+            builder.field(tuple.v2().type(), tuple.v2(), params);
             builder.endObject().endObject();
         }
         builder.endArray();

x-pack/plugin/watcher/src/test/java/org/elasticsearch/xpack/watcher/input/chain/ChainInputTests.java

@@ -9,6 +9,7 @@
 import org.elasticsearch.ElasticsearchParseException;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.xcontent.ToXContent;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -18,6 +19,7 @@
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.test.SecuritySettingsSourceField;
 import org.elasticsearch.xpack.core.watcher.execution.WatchExecutionContext;
+import org.elasticsearch.xpack.core.watcher.input.Input;
 import org.elasticsearch.xpack.core.watcher.watch.Payload;
 import org.elasticsearch.xpack.watcher.common.http.HttpRequestTemplate;
 import org.elasticsearch.xpack.watcher.common.http.auth.basic.BasicAuth;
@@ -29,6 +31,7 @@
 import org.elasticsearch.xpack.watcher.input.simple.SimpleInputFactory;
 import org.elasticsearch.xpack.watcher.test.WatcherTestUtils;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -46,6 +49,7 @@
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.sameInstance;
 
 public class ChainInputTests extends ESTestCase {
 
@@ -220,4 +224,24 @@ public void testParsingShouldBeStrictWhenStartingInputs() throws Exception {
                 expectThrows(ElasticsearchParseException.class, () -> chainInputFactory.parseInput("test", parser));
         assertThat(e.getMessage(), containsString("Expected starting JSON object after [first] in watch [test]"));
     }
+
+    public void testThatXContentParametersArePassedToInputs() throws Exception {
+        ToXContent.Params randomParams = new ToXContent.MapParams(Collections.singletonMap(randomAlphaOfLength(5), randomAlphaOfLength(5)));
+        ChainInput chainInput = new ChainInput(Collections.singletonList(Tuple.tuple("whatever", new Input() {
+            @Override
+            public String type() {
+                return "test";
+            }
+
+            @Override
+            public XContentBuilder toXContent(XContentBuilder builder, Params params) {
+                assertThat(params, sameInstance(randomParams));
+                return builder;
+            }
+        })));
+
+        try (XContentBuilder builder = jsonBuilder()) {
+            chainInput.toXContent(builder, randomParams);
+        }
+    }
 }