Change behaviour of indices segments api to allow no indices

Using '_cat/segments' or the indices segments api without matching any index
now returns empty result instead of throwing IndexMissingException.

Closes #9219

rest-api-spec/test/cat.segments/10_basic.yaml

@@ -24,6 +24,14 @@
 ---
 "Test cat segments output":
 
+  - do:
+      cat.segments:
+        v: false
+
+  - match:
+      $body: |
+               /^$/
+
   - do:
       indices.create:
         index: index1
@@ -39,7 +47,7 @@
         refresh: true
   - do:
        cluster.health:
-         wait_for_status: yellow
+         wait_for_status: green
   - do:
       cat.segments:
         v: false
@@ -57,7 +65,7 @@
             number_of_replicas: "0"
   - do:
        cluster.health:
-         wait_for_status: yellow
+         wait_for_status: green
          wait_for_relocating_shards: 0
 
   - do:
@@ -68,7 +76,7 @@
         refresh: true
   - do:
        cluster.health:
-         wait_for_status: yellow
+         wait_for_status: green
 
 
   - do:
@@ -85,3 +93,28 @@
   - match:
       $body: |
                   /^(index2 .+ \n?)$/
+
+---
+"Test cat segments on closed index behaviour":
+
+  - do:
+      indices.create:
+        index: index1
+        body:
+          settings:
+            number_of_shards: "1"
+            number_of_replicas: "0"
+
+  - do:
+       cluster.health:
+         wait_for_status: green
+
+  - do:
+    indices.close:
+      index: index1
+
+  - do:
+      catch: forbidden
+      cat.segments:
+        index: index1
+        v: false

rest-api-spec/test/indices.segments/10_basic.yaml

@@ -1,5 +1,75 @@
 ---
-"segments test":
+"no segments test":
   - do:
       indices.segments:
         allow_no_indices: true
+
+  - match:   { _shards.total: 0}
+  - match:   { indices: {}}
+
+  - do:
+      catch: missing
+      indices.segments:
+        allow_no_indices: false
+
+---
+"basic segments test":
+
+  - do:
+      indices.create:
+        index: index1
+        body:
+          settings:
+            number_of_shards: "1"
+            number_of_replicas: "0"
+  - do:
+      index:
+        index: index1
+        type: type
+        body: { foo: bar }
+        refresh: true
+
+  - do:
+       cluster.health:
+         wait_for_status: green
+
+  - do:
+      indices.segments:
+          index: index1
+
+  - match:   { _shards.total: 1}
+  - match:   { indices.index1.shards.0.0.routing.primary: true}
+  - match:   { indices.index1.shards.0.0.segments._0.num_docs: 1}
+
+---
+"closed segments test":
+
+  - do:
+      indices.create:
+        index: index1
+        body:
+          settings:
+            number_of_shards: "1"
+            number_of_replicas: "0"
+  - do:
+      index:
+        index: index1
+        type: type
+        body: { foo: bar }
+        refresh: true
+
+  - do:
+    indices.close:
+      index: index1
+
+  - do:
+      catch: forbidden
+      indices.segments:
+          index: index1
+
+  - do:
+      indices.segments:
+          index: index1
+          ignore_unavailable: true
+
+  - match:   { _shards.total: 0}

src/main/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequest.java

@@ -37,7 +37,6 @@ public class IndicesSegmentsRequest extends BroadcastOperationRequest<IndicesSeg
 
     public IndicesSegmentsRequest(String... indices) {
         super(indices);
-        indicesOptions(IndicesOptions.fromOptions(false, false, true, false));
     }
 
     /**

src/test/java/org/elasticsearch/action/admin/indices/segments/IndicesSegmentsRequestTests.java

@@ -19,11 +19,15 @@
 
 package org.elasticsearch.action.admin.indices.segments;
 
+import org.elasticsearch.action.ListenableActionFuture;
+import org.elasticsearch.action.support.IndicesOptions;
 import org.elasticsearch.common.settings.ImmutableSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.index.engine.Segment;
+import org.elasticsearch.indices.IndexClosedException;
 import org.elasticsearch.test.ElasticsearchSingleNodeTest;
 import org.junit.Before;
+import org.junit.Test;
 
 import java.util.List;
 
@@ -56,4 +60,33 @@ public class IndicesSegmentsRequestTests extends ElasticsearchSingleNodeTest {
         List<Segment> segments = rsp.getIndices().get("test").iterator().next().getShards()[0].getSegments();
         assertNotNull(segments.get(0).ramTree);
     }
+
+    /**
+     * with the default IndicesOptions inherited from BroadcastOperationRequest this will raise an exception
+     */
+    @Test(expected=org.elasticsearch.indices.IndexClosedException.class)
+    public void testRequestOnClosedIndex() {
+        client().admin().indices().prepareClose("test").get();
+        client().admin().indices().prepareSegments("test").get();
+    }
+
+    /**
+     * setting the "ignoreUnavailable" option prevents IndexClosedException
+     */
+    public void testRequestOnClosedIndexIgnoreUnavailable() {
+        client().admin().indices().prepareClose("test").get();
+        IndicesOptions defaultOptions = new IndicesSegmentsRequest().indicesOptions();
+        IndicesOptions testOptions = IndicesOptions.fromOptions(true, true, true, false, defaultOptions);
+        IndicesSegmentResponse rsp = client().admin().indices().prepareSegments("test").setIndicesOptions(testOptions).get();
+        assertEquals(0, rsp.getIndices().size());
+    }
+
+    /**
+     * by default IndicesOptions setting IndicesSegmentsRequest should not throw exception when no index present
+     */
+    public void testAllowNoIndex() {
+        client().admin().indices().prepareDelete("test").get();
+        IndicesSegmentResponse rsp = client().admin().indices().prepareSegments().get();
+        assertEquals(0, rsp.getIndices().size());
+    }
 }

src/test/java/org/elasticsearch/indices/IndicesOptionsIntegrationTests.java

@@ -362,7 +362,7 @@ public class IndicesOptionsIntegrationTests extends ElasticsearchIntegrationTest
         verify(count(indices), false);
         verify(clearCache(indices), false);
         verify(_flush(indices),false);
-        verify(segments(indices), true);
+        verify(segments(indices), false);
         verify(stats(indices), false);
         verify(optimize(indices), false);
         verify(refresh(indices), false);
@@ -437,7 +437,7 @@ public class IndicesOptionsIntegrationTests extends ElasticsearchIntegrationTest
         verify(count(indices), false, 1);
         verify(clearCache(indices), false);
         verify(_flush(indices),false);
-        verify(segments(indices), true);
+        verify(segments(indices), false);
         verify(stats(indices), false);
         verify(optimize(indices), false);
         verify(refresh(indices), false);