Adding unit test for the druid request headers.

fili-core/src/test/groovy/com/yahoo/bard/webservice/druid/client/impl/AsyncDruidWebServiceImplSpec.groovy

@@ -0,0 +1,53 @@
+package com.yahoo.bard.webservice.druid.client.impl
+
+import com.yahoo.bard.webservice.druid.client.DruidClientConfigHelper
+import com.yahoo.bard.webservice.druid.model.query.QueryContext
+import com.yahoo.bard.webservice.druid.model.query.WeightEvaluationQuery
+
+import com.fasterxml.jackson.databind.ObjectMapper
+
+import io.netty.handler.codec.http.HttpHeaders
+import spock.lang.Specification
+
+import java.util.function.Supplier
+
+class AsyncDruidWebServiceImplSpec extends Specification {
+    def "Ensure that headersToAppend are added"() {
+        setup:
+        WeightEvaluationQuery weightEvaluationQuery = Mock(WeightEvaluationQuery)
+        QueryContext queryContext = Mock(QueryContext)
+        weightEvaluationQuery.getContext() >> { queryContext }
+        queryContext.numberOfQueries() >> { 1 }
+        queryContext.getSequenceNumber() >> { 1 }
+
+        when:
+        Map<String, String> expectedHeaders = new HashMap<>()
+        expectedHeaders.put("k1", "v1")
+        expectedHeaders.put("k2", "v2")
+        Supplier<Map<String, String>> supplier = new Supplier<Map<String, String>>() {
+            @Override
+            Map<String, String> get() {
+                return expectedHeaders
+            }
+        }
+
+        AsyncDruidWebServiceImplWrapper webServiceImplWrapper = new AsyncDruidWebServiceImplWrapper(
+                DruidClientConfigHelper.getNonUiServiceConfig(),
+                new ObjectMapper(),
+                supplier
+        )
+        webServiceImplWrapper.postDruidQuery(
+                null,
+                null,
+                null,
+                null,
+                weightEvaluationQuery
+        );
+
+        then:
+        HttpHeaders actualHeaders = webServiceImplWrapper.getHeaders()
+        for (Map.Entry<String, String> header : expectedHeaders) {
+            actualHeaders.get(header.getKey()) == header.getValue()
+        }
+    }
+}

fili-core/src/test/java/com/yahoo/bard/webservice/druid/client/impl/AsyncDruidWebServiceImplWrapper.java

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+// Copyright 2016 Yahoo Inc.
+// Licensed under the terms of the Apache license. Please see LICENSE.md file distributed with this work for terms.
+package com.yahoo.bard.webservice.druid.client.impl;
+
+import com.yahoo.bard.webservice.druid.client.DruidServiceConfig;
+import com.yahoo.bard.webservice.druid.client.FailureCallback;
+import com.yahoo.bard.webservice.druid.client.HttpErrorCallback;
+import com.yahoo.bard.webservice.druid.client.SuccessCallback;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+import org.asynchttpclient.BoundRequestBuilder;
+import org.asynchttpclient.Request;
+
+import io.netty.handler.codec.http.HttpHeaders;
+
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.function.Supplier;
+
+/**
+ * Used for testing AsyncDruidWebServiceImpl.
+ */
+public class AsyncDruidWebServiceImplWrapper extends AsyncDruidWebServiceImpl {
+    public Request request;
+
+    /**
+     * Constructor wrapper.
+     *
+     * @param serviceConfig Service config
+     * @param mapper Mapper
+     * @param headersToAppend Headers
+     */
+    public AsyncDruidWebServiceImplWrapper(
+            DruidServiceConfig serviceConfig,
+            ObjectMapper mapper,
+            Supplier<Map<String, String>> headersToAppend
+    ) {
+        super(serviceConfig, mapper, headersToAppend);
+    }
+
+    /**
+     * Capture arguments to test for expected values.
+     *
+     * @param success  callback for handling successful requests.
+     * @param error  callback for handling http errors.
+     * @param failure  callback for handling exception failures.
+     * @param requestBuilder  The bound request builder for the request to be sent.
+     * @param timerName  The name that distinguishes this request as part of a druid query or segment metadata request
+     * @param outstanding  The counter that keeps track of the outstanding (in flight) requests for the top level query
+     */
+    @Override
+    protected void sendRequest(
+            final SuccessCallback success,
+            final HttpErrorCallback error,
+            final FailureCallback failure,
+            final BoundRequestBuilder requestBuilder,
+            final String timerName,
+            final AtomicLong outstanding
+    ) {
+        this.request = requestBuilder.build();
+    }
+
+    public HttpHeaders getHeaders() {
+        return request.getHeaders();
+    }
+}