Issue #7102 - WebClient should have a mode that is resilient to bad m…

…edia/content types (#9040)

common/http/src/main/java/io/helidon/common/http/MediaType.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2022 Oracle and/or its affiliates.
+ * Copyright (c) 2018, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -268,6 +268,12 @@ public final class MediaType implements AcceptPredicate<MediaType> {
      */
     private static final CharMatcher LINEAR_WHITE_SPACE = CharMatcher.anyOf(" \t\r\n");
     private static final String CHARSET_ATTRIBUTE = "charset";
+
+    // Relaxed media types mapping
+    private static final Map<String, MediaType> RELAXED_TYPES = Map.of(
+            "text",  MediaType.TEXT_PLAIN // text -> text/plain
+    );
+
     private final String type;
     private final String subtype;
     private final Map<String, String> parameters;
@@ -319,13 +325,43 @@ public static MediaType create(String type, String subtype) {
      * @throws NullPointerException     if the input is {@code null}
      */
     public static MediaType parse(String input) {
+        return parse(input, true);
+    }
+
+    /**
+     * Parses a media type from its string representation in relaxed mode.
+     * Predefined incomplete media types are replaced with corresponding valid media types.
+     *
+     * @param input the input string representing a media type
+     * @return parsed {@link MediaType} instance
+     * @throws IllegalArgumentException if the input is not parsable
+     * @throws NullPointerException     if the input is {@code null}
+     */
+    public static MediaType parseRelaxed(String input) {
+        return parse(input, false);
+    }
+
+    /**
+     * Parses a media type from its string representation.
+     *
+     * @param input the input string representing a media type
+     * @param strictMode whether strict mode (default) shall be used
+     * @return parsed {@link MediaType} instance
+     * @throws IllegalArgumentException if the input is not parsable
+     * @throws NullPointerException     if the input is {@code null}
+     */
+    private static MediaType parse(String input, boolean strictMode) {
         Objects.requireNonNull(input, "Parameter 'input' is null!");
         Tokenizer tokenizer = new Tokenizer(input);
         try {
             String type = tokenizer.consumeToken(TOKEN_MATCHER);
+            Map<String, String> parameters = new HashMap<>();
+            // Handle relaxed media type parsing when '/' character is not present
+            if (!strictMode && !tokenizer.hasMore() && RELAXED_TYPES.containsKey(type)) {
+                return RELAXED_TYPES.get(type);
+            }
             tokenizer.consumeCharacter('/');
             String subtype = tokenizer.consumeToken(TOKEN_MATCHER);
-            Map<String, String> parameters = new HashMap<>();
             while (tokenizer.hasMore()) {
                 tokenizer.consumeTokenIfPresent(LINEAR_WHITE_SPACE);
                 tokenizer.consumeCharacter(';');

tests/integration/webclient/src/test/java/io/helidon/tests/integration/webclient/HeadersTest.java

@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2024 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.helidon.tests.integration.webclient;
+
+import java.util.Optional;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+import io.helidon.common.http.Http;
+import io.helidon.common.http.MediaType;
+import io.helidon.webclient.WebClient;
+import io.helidon.webclient.WebClientResponse;
+import io.helidon.webserver.Routing;
+import io.helidon.webserver.ServerRequest;
+import io.helidon.webserver.ServerResponse;
+import io.helidon.webserver.WebServer;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.CoreMatchers.instanceOf;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.notNullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.fail;
+
+public class HeadersTest {
+
+    private static final String INVALID_CONTENT_TYPE_VALUE = "invalid header value";
+    private static final String INVALID_CONTENT_TYPE_TEXT = "text";
+    private static final String RELAXED_CONTENT_TYPE_TEXT = "text/plain";
+
+    private static WebServer server;
+    private static WebClient client;
+
+    @BeforeAll
+    static void beforeAll() throws ExecutionException, InterruptedException, TimeoutException {
+        server = WebServer.builder(
+                        Routing.builder()
+                                .get("/invalidContentType", HeadersTest::invalidContentType)
+                                .get("/invalidTextContentType", HeadersTest::invalidTextContentType)
+                                .build()
+                )
+                .build();
+        server.start()
+                .toCompletableFuture()
+                .get(10, TimeUnit.SECONDS);
+
+        client = WebClient.builder()
+                .baseUri("http://localhost:" + server.port())
+                .validateHeaders(false)
+                .keepAlive(true)
+                .build();
+    }
+
+    // HTTP service with invalid Content-Type
+    private static void invalidContentType(ServerRequest request, ServerResponse response) {
+        response.addHeader(Http.Header.CONTENT_TYPE, INVALID_CONTENT_TYPE_VALUE)
+                .send();
+    }
+
+    // HTTP service with Content-Type: text instead of text/plain
+    private static void invalidTextContentType(ServerRequest request, ServerResponse response) {
+        response.addHeader(Http.Header.CONTENT_TYPE, INVALID_CONTENT_TYPE_TEXT)
+                .send();
+    }
+
+    @AfterAll
+    static void afterAll() throws ExecutionException, InterruptedException, TimeoutException {
+        if (server != null) {
+            server.shutdown()
+                    .toCompletableFuture()
+                    .get(10, TimeUnit.SECONDS);
+        }
+    }
+
+    // Verify that invalid content type causes an exception when being parsed
+    @Test
+    void testInvalidContentType() {
+        try {
+            client.get()
+                    .path("/invalidContentType")
+                    .request()
+                    .await(10, TimeUnit.SECONDS);
+            fail("WebClient shall throw an exception");
+        } catch (Exception ex) {
+            assertThat(ex, is(instanceOf(CompletionException.class)));
+            Throwable cause = ex.getCause();
+            assertThat(cause, is(notNullValue()));
+            assertThat(cause, is(instanceOf(IllegalArgumentException.class)));
+            assertThat(cause.getMessage(), containsString(INVALID_CONTENT_TYPE_VALUE));
+        }
+    }
+
+    // Verify that "text" content type causes an exception when being parsed in strict mode
+    @Test
+    void testInvalidTextContentTypeStrict() {
+        try {
+            client.get()
+                    .path("/invalidTextContentType")
+                    .request()
+                    .await(10, TimeUnit.SECONDS);
+        } catch (Exception ex) {
+            assertThat(ex, is(instanceOf(CompletionException.class)));
+            Throwable cause = ex.getCause();
+            assertThat(cause, is(notNullValue()));
+            assertThat(cause, is(instanceOf(IllegalArgumentException.class)));
+            assertThat(cause.getMessage(), containsString(INVALID_CONTENT_TYPE_TEXT));
+        }
+    }
+
+    // Verify that "text" content type is transformed to "text/plain" in relaxed mode
+    @Test
+    void testInvalidTextContentTypeRelaxed() {
+        WebClient client = WebClient.builder()
+                .baseUri("http://localhost:" + server.port())
+                .validateHeaders(false)
+                .keepAlive(true)
+                .mediaTypeParserRelaxed(true)
+                .build();
+        WebClientResponse response = client.get()
+                .path("/invalidTextContentType")
+                .request()
+                .await(10, TimeUnit.SECONDS);
+        Optional<MediaType> maybeContentType = response.headers().contentType();
+        assertThat(maybeContentType.isPresent(), is(true));
+        assertThat(maybeContentType.get().toString(), is(RELAXED_CONTENT_TYPE_TEXT));
+    }
+
+}

webclient/webclient/src/main/java/io/helidon/webclient/NettyClientHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -123,7 +123,8 @@ protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws IO
                     .status(helidonStatus(response.status()))
                     .httpVersion(Http.Version.create(response.protocolVersion().toString()))
                     .responseCloser(responseCloser)
-                    .lastEndpointURI(requestConfiguration.requestURI());
+                    .lastEndpointURI(requestConfiguration.requestURI())
+                    .mediaTypeParserRelaxed(requestConfiguration.mediaTypeParserRelaxed());
 
             HttpHeaders nettyHeaders = response.headers();
             for (String name : nettyHeaders.names()) {

webclient/webclient/src/main/java/io/helidon/webclient/WebClient.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -440,6 +440,21 @@ public Builder enableAutomaticCookieStore(boolean enableAutomaticCookieStore) {
             return this;
         }
 
+        /**
+         * Configure media type parsing mode for HTTP {@code Content-Type} header.
+         * Media type parsing in relaxed mode accepts incomplete Content-Type values like
+         * {@code "text"}, which are accepted as corresponding complete value, e.g. {@code "text/plain"}.
+         * Parsing in strict mode (default) expect exact {@code Content-Type} matching.
+         *
+         * @param relaxedMode value of {@code true} sets relaxed media type parsing mode,
+         *                    value of {@code false} sets strict media type parsing mode
+         * @return updated builder instance
+         */
+        public Builder mediaTypeParserRelaxed(boolean relaxedMode) {
+            configuration.mediaTypeParserRelaxed(relaxedMode);
+            return this;
+        }
+
         WebClientConfiguration configuration() {
             configuration.clientServices(services());
             return configuration.build();

webclient/webclient/src/main/java/io/helidon/webclient/WebClientConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2019, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -84,6 +84,7 @@ class WebClientConfiguration {
     private final boolean validateHeaders;
     private final boolean relativeUris;
     private final DnsResolverType dnsResolverType;
+    private final boolean mediaTypeParserRelaxed;
 
     /**
      * Creates a new instance of client configuration.
@@ -115,6 +116,7 @@ class WebClientConfiguration {
         this.validateHeaders = builder.validateHeaders;
         this.relativeUris = builder.relativeUris;
         this.dnsResolverType = builder.dnsResolverType;
+        this.mediaTypeParserRelaxed = builder.mediaTypeParserRelaxed;
     }
 
     /**
@@ -291,6 +293,10 @@ DnsResolverType dnsResolverType() {
         return dnsResolverType;
     }
 
+    boolean mediaTypeParserRelaxed() {
+        return mediaTypeParserRelaxed;
+    }
+
     /**
      * A fluent API builder for {@link WebClientConfiguration}.
      */
@@ -323,6 +329,7 @@ static class Builder<B extends Builder<B, T>, T extends WebClientConfiguration>
         private boolean validateHeaders;
         private boolean relativeUris;
         private DnsResolverType dnsResolverType;
+        private boolean mediaTypeParserRelaxed;
         @SuppressWarnings("unchecked")
         private B me = (B) this;
 
@@ -635,6 +642,11 @@ B clientServices(List<WebClientService> clientServices) {
             return me;
         }
 
+        B mediaTypeParserRelaxed(boolean relaxedMode) {
+            this.mediaTypeParserRelaxed = relaxedMode;
+            return me;
+        }
+
         /**
          * Enable keep alive option on the connection.
          *
@@ -699,6 +711,10 @@ public B keepAlive(boolean keepAlive) {
          *     <td>proxy</td>
          *     <td>Proxy configuration. See {@link Proxy.Builder#config(Config)}</td>
          * </tr>
+         * <tr>
+         *     <td>media-type-parser-relaxed</td>
+         *     <td>Whether relaxed media type parsing mode should be used.</td>
+         * </tr>
          * </table>
          *
          * @param config config
@@ -729,6 +745,7 @@ public B config(Config config) {
             config.get("dns-resolver-type").asString()
                     .map(s -> DnsResolverType.valueOf(s.toUpperCase()))
                     .ifPresent(this::dnsResolverType);
+            config.get("media-type-parser-relaxed").asBoolean().ifPresent(this::mediaTypeParserRelaxed);
             return me;
         }
 
@@ -757,6 +774,7 @@ public B update(WebClientConfiguration configuration) {
             keepAlive(configuration.keepAlive);
             validateHeaders(configuration.validateHeaders);
             dnsResolverType(configuration.dnsResolverType);
+            mediaTypeParserRelaxed(configuration.mediaTypeParserRelaxed);
             configuration.cookieManager.defaultCookies().forEach(this::defaultCookie);
             config = configuration.config;
 

webclient/webclient/src/main/java/io/helidon/webclient/WebClientResponseHeadersImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2022 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,8 +32,22 @@
  */
 class WebClientResponseHeadersImpl extends ReadOnlyHeaders implements WebClientResponseHeaders {
 
-    private WebClientResponseHeadersImpl(Map<String, List<String>> headers) {
+    private final boolean mediaTypeParserRelaxed;
+
+    private WebClientResponseHeadersImpl(Map<String, List<String>> headers, boolean mediaTypeParserRelaxed) {
         super(headers);
+        this.mediaTypeParserRelaxed = mediaTypeParserRelaxed;
+    }
+
+    /**
+     * Creates {@link WebClientResponseHeaders} instance which contains data from {@link Map}.
+     *
+     * @param headers response headers in map
+     * @param mediaTypeParserRelaxed whether relaxed media type parsing mode should be used
+     * @return response headers instance
+     */
+    protected static WebClientResponseHeadersImpl create(Map<String, List<String>> headers, boolean mediaTypeParserRelaxed) {
+        return new WebClientResponseHeadersImpl(headers, mediaTypeParserRelaxed);
     }
 
     /**
@@ -43,7 +57,7 @@ private WebClientResponseHeadersImpl(Map<String, List<String>> headers) {
      * @return response headers instance
      */
     protected static WebClientResponseHeadersImpl create(Map<String, List<String>> headers) {
-        return new WebClientResponseHeadersImpl(headers);
+        return new WebClientResponseHeadersImpl(headers, false);
     }
 
     @Override
@@ -76,7 +90,10 @@ public Optional<ZonedDateTime> date() {
 
     @Override
     public Optional<MediaType> contentType() {
-        return first(Http.Header.CONTENT_TYPE).map(MediaType::parse);
+        return first(Http.Header.CONTENT_TYPE)
+                .map(mediaTypeParserRelaxed
+                             ? MediaType::parseRelaxed
+                             : MediaType::parse);
     }
 
     @Override