Treating response header names as case-insensitive

masseyke · Sep 20, 2023 · ce8a5b3 · ce8a5b3
1 parent 32baf87
commit ce8a5b3
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Showing 2 changed files with 12 additions and 5 deletions.
diff --git a/.../plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/common/http/HttpClient.java b/.../plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/common/http/HttpClient.java
@@ -72,6 +72,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;
@@ -274,17 +275,22 @@ public HttpResponse execute(HttpRequest request) throws IOException {
             // headers
             Header[] headers = response.getAllHeaders();
             Map<String, String[]> responseHeaders = Maps.newMapWithExpectedSize(headers.length);
+            /*
+             * Headers are not case sensitive, so in the following loop we lowercase all of them. We also roll up all values for the same
+             * case-insensitive header into a list.
+             */
             for (Header header : headers) {
-                if (responseHeaders.containsKey(header.getName())) {
-                    String[] old = responseHeaders.get(header.getName());
+                String lowerCaseHeaderName = header.getName().toLowerCase(Locale.ROOT);
+                if (responseHeaders.containsKey(lowerCaseHeaderName)) {
+                    String[] old = responseHeaders.get(lowerCaseHeaderName);
                     String[] values = new String[old.length + 1];
 
                     System.arraycopy(old, 0, values, 0, old.length);
                     values[values.length - 1] = header.getValue();
 
-                    responseHeaders.put(header.getName(), values);
+                    responseHeaders.put(lowerCaseHeaderName, values);
                 } else {
-                    responseHeaders.put(header.getName(), new String[] { header.getValue() });
+                    responseHeaders.put(lowerCaseHeaderName, new String[] { header.getValue() });
                 }
             }
 

diff --git a/...in/watcher/src/test/java/org/elasticsearch/xpack/watcher/common/http/HttpClientTests.java b/...in/watcher/src/test/java/org/elasticsearch/xpack/watcher/common/http/HttpClientTests.java
@@ -500,6 +500,7 @@ public void testThatDuplicateHeaderKeysAreReturned() throws Exception {
             .setBody("foo")
             .addHeader("foo", "bar")
             .addHeader("foo", "baz")
+            .addHeader("Foo", "bam")
             .addHeader("Content-Length", "3");
         webServer.enqueue(mockResponse);
 
@@ -509,7 +510,7 @@ public void testThatDuplicateHeaderKeysAreReturned() throws Exception {
         assertThat(webServer.requests(), hasSize(1));
 
         assertThat(httpResponse.headers(), hasKey("foo"));
-        assertThat(httpResponse.headers().get("foo"), containsInAnyOrder("bar", "baz"));
+        assertThat(httpResponse.headers().get("foo"), containsInAnyOrder("bar", "baz", "bam"));
     }
 
     // finally fixing https://github.com/elastic/x-plugins/issues/1141 - yay! Fixed due to switching to apache http client internally!