H2 conversion support OWS for connection header csv (#2400)

Motivation:
H2 doesn't support the connection header, and must remove
all headers that are referenced in the value of the conneciton
header. In the event the connection header contains a CSV we should
support OWS.

Author: Scottmitch

servicetalk-http-netty/src/main/java/io/servicetalk/http/netty/H2ToStH1Utils.java

@@ -159,16 +159,20 @@ static Http2Headers h1HeadersToH2Headers(HttpHeaders h1Headers) {
         Iterator<? extends CharSequence> connectionItr = h1Headers.valuesIterator(CONNECTION);
         if (connectionItr.hasNext()) {
             do {
-                String connectionHeader = connectionItr.next().toString();
+                CharSequence connectionHeader = connectionItr.next();
                 connectionItr.remove();
-                int i = connectionHeader.indexOf(',');
+                int i = indexOf(connectionHeader, ',', 0);
                 if (i != -1) {
                     int start = 0;
                     do {
-                        h1Headers.remove(connectionHeader.substring(start, i));
+                        h1Headers.remove(connectionHeader.subSequence(start, i));
                         start = i + 1;
-                    } while (start < connectionHeader.length() && (i = connectionHeader.indexOf(',', start)) != -1);
-                    h1Headers.remove(connectionHeader.substring(start));
+                        // Skip OWS
+                        if (start < connectionHeader.length() && connectionHeader.charAt(start) == ' ') {
+                            ++start;
+                        }
+                    } while (start < connectionHeader.length() && (i = indexOf(connectionHeader, ',', start)) != -1);
+                    h1Headers.remove(connectionHeader.subSequence(start, connectionHeader.length()));
                 } else {
                     h1Headers.remove(connectionHeader);
                 }

servicetalk-http-netty/src/test/java/io/servicetalk/http/netty/H2PriorKnowledgeFeatureParityTest.java

@@ -197,9 +197,14 @@
 import static org.junit.jupiter.api.Assumptions.assumeTrue;
 
 class H2PriorKnowledgeFeatureParityTest {
-
     private static final CharSequence[] PROHIBITED_HEADERS = {CONNECTION, KEEP_ALIVE, TRANSFER_ENCODING, UPGRADE,
             PROXY_CONNECTION};
+    private static final String CONNECTION_HEADER1 = "conn1";
+    private static final String CONNECTION_HEADER2 = "conn2";
+    private static final String CONNECTION_HEADER3 = "conn3";
+    private static final String CONNECTION_HEADER4 = "conn4";
+    private static final CharSequence[] CONNECTION_HEADERS = {CONNECTION_HEADER1, CONNECTION_HEADER2,
+            CONNECTION_HEADER3, CONNECTION_HEADER4};
     private static final String EXPECT_FAIL_HEADER = "please_fail_expect";
     private static final ContextMap.Key<String> K1 = newKey("k1", String.class);
     private static final ContextMap.Key<String> K2 = newKey("k2", String.class);
@@ -1439,7 +1444,7 @@ protected void initChannel(final Channel ch) {
                 }, __ -> { }, identity());
         InetSocketAddress serverAddress = (InetSocketAddress) serverAcceptorChannel.localAddress();
         try (BlockingHttpClient client = forSingleAddress(HostAndPort.of(serverAddress))
-                .protocols(HttpProtocol.HTTP_2.config)
+                .protocols(HttpProtocol.HTTP_2.configOtherHeaderFactory)
                 .enableWireLogging("servicetalk-tests-wire-logger", LogLevel.TRACE, () -> true)
                 .executionStrategy(clientExecutionStrategy)
                 .buildBlocking()) {
@@ -1453,7 +1458,7 @@ protected void initChannel(final Channel ch) {
     void h2LayerFiltersOutProhibitedH1HeadersOnServerSide() throws Exception {
         setUp(DEFAULT, true);
         try (ServerContext serverContext = HttpServers.forAddress(localAddress(0))
-                .protocols(HttpProtocol.HTTP_2.config)
+                .protocols(HttpProtocol.HTTP_2.configOtherHeaderFactory)
                 .enableWireLogging("servicetalk-tests-wire-logger", LogLevel.TRACE, () -> true)
                 .listenBlockingAndAwait((ctx, request, responseFactory) -> addProhibitedHeaders(responseFactory.ok()));
              BlockingHttpClient client = forSingleAddress(serverHostAndPort(serverContext))
@@ -1467,11 +1472,21 @@ void h2LayerFiltersOutProhibitedH1HeadersOnServerSide() throws Exception {
                 assertThat("Unexpected headerName: " + headerName,
                         response.headers().contains(headerName), is(false));
             }
+            for (CharSequence headerName : CONNECTION_HEADERS) {
+                assertThat("Unexpected headerName: " + headerName,
+                        response.headers().contains(headerName), is(false));
+            }
         }
     }
 
     private static <T extends HttpMetaData> T addProhibitedHeaders(T metaData) {
         metaData.addHeader(CONNECTION, UPGRADE)
+                .addHeader(CONNECTION, CONNECTION_HEADER1 + "," + CONNECTION_HEADER2)
+                .addHeader(CONNECTION, CONNECTION_HEADER3 + ", " + CONNECTION_HEADER4)
+                .addHeader(CONNECTION_HEADER1, "foo")
+                .addHeader(CONNECTION_HEADER2, "bar")
+                .addHeader(CONNECTION_HEADER3, "baz")
+                .addHeader(CONNECTION_HEADER4, "boo")
                 .addHeader(KEEP_ALIVE, "timeout=5")
                 .addHeader(TRANSFER_ENCODING, CHUNKED)
                 .addHeader(UPGRADE, "foo/2")
@@ -2072,7 +2087,17 @@ private static boolean allHeadersSanitized(Http2Headers headers) {
             return !headers.contains(HttpHeaderNames.CONNECTION) && !headers.contains(HttpHeaderNames.KEEP_ALIVE)
                     && !headers.contains(HttpHeaderNames.TRANSFER_ENCODING)
                     && !headers.contains(HttpHeaderNames.UPGRADE)
-                    && !headers.contains(HttpHeaderNames.PROXY_CONNECTION);
+                    && !headers.contains(HttpHeaderNames.PROXY_CONNECTION) &&
+                    allConnHeadersSanitized(headers);
+        }
+
+        private static boolean allConnHeadersSanitized(Http2Headers headers) {
+            for (CharSequence headerName : CONNECTION_HEADERS) {
+                if (headers.contains(headerName)) {
+                    return false;
+                }
+            }
+            return true;
         }
     }
 

servicetalk-http-netty/src/test/java/io/servicetalk/http/netty/HttpProtocol.java

@@ -21,21 +21,25 @@
 import java.util.Arrays;
 import java.util.Collection;
 
+import static io.servicetalk.http.api.DefaultHttpHeadersFactory.INSTANCE;
 import static io.servicetalk.http.api.HttpProtocolVersion.HTTP_1_1;
 import static io.servicetalk.http.api.HttpProtocolVersion.HTTP_2_0;
+import static io.servicetalk.http.netty.HttpProtocolConfigs.h1;
 import static io.servicetalk.http.netty.HttpProtocolConfigs.h1Default;
 import static io.servicetalk.http.netty.HttpProtocolConfigs.h2;
 import static io.servicetalk.logging.api.LogLevel.TRACE;
 
 enum HttpProtocol {
-    HTTP_1(h1Default(), HTTP_1_1),
-    HTTP_2(h2().enableFrameLogging("servicetalk-tests-h2-frame-logger", TRACE, () -> true).build(), HTTP_2_0);
+    HTTP_1(h1Default(), h1().headersFactory(new H2HeadersFactory(true, true, false)).build(), HTTP_1_1),
+    HTTP_2(applyFrameLogger(h2()).build(), applyFrameLogger(h2()).headersFactory(INSTANCE).build(), HTTP_2_0);
 
+    final HttpProtocolConfig configOtherHeaderFactory;
     final HttpProtocolConfig config;
     final HttpProtocolVersion version;
 
-    HttpProtocol(HttpProtocolConfig config, HttpProtocolVersion version) {
+    HttpProtocol(HttpProtocolConfig config, HttpProtocolConfig configOtherHeaderFactory, HttpProtocolVersion version) {
         this.config = config;
+        this.configOtherHeaderFactory = configOtherHeaderFactory;
         this.version = version;
     }
 
@@ -46,4 +50,8 @@ static HttpProtocolConfig[] toConfigs(Collection<HttpProtocol> protocols) {
     static HttpProtocolConfig[] toConfigs(HttpProtocol[] protocols) {
         return Arrays.stream(protocols).map(p -> p.config).toArray(HttpProtocolConfig[]::new);
     }
+
+    private static H2ProtocolConfigBuilder applyFrameLogger(H2ProtocolConfigBuilder builder) {
+        return builder.enableFrameLogging("servicetalk-tests-h2-frame-logger", TRACE, () -> true);
+    }
 }