1 files changed, 41 insertions, 0 deletions
diff --git a/container-search/src/main/java/com/yahoo/search/dispatch/InvokerFactory.java b/container-search/src/main/java/com/yahoo/search/dispatch/InvokerFactory.java
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+++ b/container-search/src/main/java/com/yahoo/search/dispatch/InvokerFactory.java
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+// Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.search.dispatch;
+
+import com.yahoo.prelude.fastsearch.VespaBackEndSearcher;
+import com.yahoo.search.Query;
+import com.yahoo.search.Result;
+import com.yahoo.search.dispatch.searchcluster.Node;
+import com.yahoo.search.result.Coverage;
+import com.yahoo.search.result.ErrorMessage;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.OptionalInt;
+import java.util.Set;
+
+/**
+ * @author ollivir
+ */
+public abstract class InvokerFactory {
+    public abstract Optional<SearchInvoker> createSearchInvoker(VespaBackEndSearcher searcher, Query query, OptionalInt groupId,
+            List<Node> nodes, boolean acceptIncompleteCoverage);
+
+    public abstract Optional<FillInvoker> createFillInvoker(VespaBackEndSearcher searcher, Result result);
+
+    protected static SearchInvoker createCoverageErrorInvoker(List<Node> nodes, Set<Integer> failed) {
+        StringBuilder down = new StringBuilder("Connection failure on nodes with distribution-keys: ");
+        int count = 0;
+        for (Node node : nodes) {
+            if (failed.contains(node.key())) {
+                if (count > 0) {
+                    down.append(", ");
+                }
+                count++;
+                down.append(node.key());
+            }
+        }
+        Coverage coverage = new Coverage(0, 0, 0);
+        coverage.setNodesTried(count);
+        return new SearchErrorInvoker(ErrorMessage.createBackendCommunicationError(down.toString()), coverage);
+    }
+}