Do not reject UNKNOWN HttpMethod

core/src/main/java/com/linecorp/armeria/server/DefaultServerConfig.java

@@ -111,6 +111,7 @@ final class DefaultServerConfig implements ServerConfig {
     private final boolean enableDateHeader;
     private final ServerErrorHandler errorHandler;
     private final Http1HeaderNaming http1HeaderNaming;
+    private final List<String> additionalAllowedHttpMethods;
     private final DependencyInjector dependencyInjector;
     private final Function<String, String> absoluteUriTransformer;
     private final long unloggedExceptionsReportIntervalMillis;
@@ -148,6 +149,7 @@ final class DefaultServerConfig implements ServerConfig {
             ServerErrorHandler errorHandler,
             @Nullable Mapping<String, SslContext> sslContexts,
             Http1HeaderNaming http1HeaderNaming,
+            List<String> additionalAllowedHttpMethods,
             DependencyInjector dependencyInjector,
             Function<? super String, String> absoluteUriTransformer,
             long unloggedExceptionsReportIntervalMillis,
@@ -259,6 +261,8 @@ final class DefaultServerConfig implements ServerConfig {
         this.errorHandler = requireNonNull(errorHandler, "errorHandler");
         this.sslContexts = sslContexts;
         this.http1HeaderNaming = requireNonNull(http1HeaderNaming, "http1HeaderNaming");
+        this.additionalAllowedHttpMethods = ImmutableList.copyOf(
+                requireNonNull(additionalAllowedHttpMethods, "additionalAllowedHttpMethods"));
         this.dependencyInjector = requireNonNull(dependencyInjector, "dependencyInjector");
         @SuppressWarnings("unchecked")
         final Function<String, String> castAbsoluteUriTransformer =
@@ -654,6 +658,11 @@ public Http1HeaderNaming http1HeaderNaming() {
         return http1HeaderNaming;
     }
 
+    @Override
+    public List<String> additionalAllowedHttpMethods() {
+        return additionalAllowedHttpMethods;
+    }
+
     @Override
     public DependencyInjector dependencyInjector() {
         return dependencyInjector;

core/src/main/java/com/linecorp/armeria/server/Http1RequestDecoder.java

@@ -197,11 +197,11 @@ public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception
                                                       cfg, scheme.toString(), reqTarget);
                     // Do not accept unsupported methods.
                     final HttpMethod method = headers.method();
-                    switch (method) {
-                        case CONNECT:
-                        case UNKNOWN:
-                            fail(id, headers, HttpStatus.METHOD_NOT_ALLOWED, "Unsupported method", null);
-                            return;
+                    if (method == HttpMethod.CONNECT
+                        || (method == HttpMethod.UNKNOWN
+                        && !cfg.additionalAllowedHttpMethods().contains(headers.get(com.linecorp.armeria.common.HttpHeaderNames.METHOD)))) {
+                        fail(id, headers, HttpStatus.METHOD_NOT_ALLOWED, "Unsupported method", null);
+                        return;
                     }
 
                     // Do not accept the request path '*' for a non-OPTIONS request.

core/src/main/java/com/linecorp/armeria/server/Http2RequestDecoder.java

@@ -158,8 +158,11 @@ public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers
                     }
                     break;
                 case UNKNOWN:
-                    writeUnsupportedMethodResponse(streamId, headers);
-                    return;
+                    if (!cfg.additionalAllowedHttpMethods().contains(headers.get(com.linecorp.armeria.common.HttpHeaderNames.METHOD))) {
+                        writeUnsupportedMethodResponse(streamId, headers);
+                        return;
+                    }
+                    break;
             }
 
             // Do not accept the request path '*' for a non-OPTIONS request.

core/src/main/java/com/linecorp/armeria/server/ServerBuilder.java

@@ -41,6 +41,7 @@
 import java.security.cert.X509Certificate;
 import java.time.Duration;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
@@ -73,6 +74,7 @@
 import com.linecorp.armeria.common.Flags;
 import com.linecorp.armeria.common.Http1HeaderNaming;
 import com.linecorp.armeria.common.HttpHeaderNames;
+import com.linecorp.armeria.common.HttpMethod;
 import com.linecorp.armeria.common.HttpRequest;
 import com.linecorp.armeria.common.HttpResponse;
 import com.linecorp.armeria.common.Request;
@@ -229,6 +231,7 @@ public final class ServerBuilder implements TlsSetters, ServiceConfigsBuilder<Se
     private boolean enableServerHeader = true;
     private boolean enableDateHeader = true;
     private Http1HeaderNaming http1HeaderNaming = Http1HeaderNaming.ofDefault();
+    private final List<String> additionalAllowedHttpMethods = new ArrayList<>();
     @Nullable
     private DependencyInjector dependencyInjector;
     private Function<? super String, String> absoluteUriTransformer = Function.identity();
@@ -2220,6 +2223,17 @@ public ServerBuilder http1HeaderNaming(Http1HeaderNaming http1HeaderNaming) {
         return this;
     }
 
+    /**
+     * Adds additional allowed HTTP methods to the default set of allowed {@link HttpMethod}s.
+     *
+     * @param additionalAllowedHttpMethods the additional allowed HTTP methods
+     */
+    public ServerBuilder additionalAllowedHttpMethods(String... additionalAllowedHttpMethods) {
+        requireNonNull(additionalAllowedHttpMethods, "additionalAllowedHttpMethods");
+        this.additionalAllowedHttpMethods.addAll(Arrays.asList(additionalAllowedHttpMethods));
+        return this;
+    }
+
     /**
      * Sets the interval between reporting exceptions which is not logged
      * by any decorators or services such as {@link LoggingService}.
@@ -2427,7 +2441,7 @@ ports, setSslContextIfAbsent(defaultVirtualHost, defaultSslContext),
                 childChannelPipelineCustomizer,
                 clientAddressSources, clientAddressTrustedProxyFilter, clientAddressFilter, clientAddressMapper,
                 enableServerHeader, enableDateHeader, errorHandler, sslContexts,
-                http1HeaderNaming, dependencyInjector, absoluteUriTransformer,
+                http1HeaderNaming, additionalAllowedHttpMethods, dependencyInjector, absoluteUriTransformer,
                 unloggedExceptionsReportIntervalMillis, ImmutableList.copyOf(shutdownSupports));
     }
 

core/src/main/java/com/linecorp/armeria/server/ServerConfig.java

@@ -335,6 +335,11 @@ default boolean shutdownBlockingTaskExecutorOnStop() {
      */
     Http1HeaderNaming http1HeaderNaming();
 
+    /**
+     * Returns the list of HTTP methods that are allowed to be used in addition to the standard HTTP methods.
+     */
+    List<String> additionalAllowedHttpMethods();
+
     /**
      * Returns the {@link DependencyInjector} that injects dependencies in annotations.
      */

core/src/main/java/com/linecorp/armeria/server/UpdatableServerConfig.java

@@ -305,6 +305,11 @@ public Http1HeaderNaming http1HeaderNaming() {
         return delegate.http1HeaderNaming();
     }
 
+    @Override
+    public List<String> additionalAllowedHttpMethods() {
+        return delegate.additionalAllowedHttpMethods();
+    }
+
     @Override
     public DependencyInjector dependencyInjector() {
         return delegate.dependencyInjector();

tomcat10/src/main/java/com/linecorp/armeria/server/tomcat/TomcatService.java

@@ -532,8 +532,7 @@ private Request convertRequest(ServiceRequestContext ctx, String mappedPath, Agg
         coyoteReq.protocol().setString(ctx.sessionProtocol().isMultiplex() ? "HTTP/2.0" : "HTTP/1.1");
 
         // Set the method.
-        final HttpMethod method = req.method();
-        coyoteReq.method().setString(method.name());
+        coyoteReq.method().setString(req.headers().get(HttpHeaderNames.METHOD));
 
         // Set the request URI.
         final byte[] uriBytes = mappedPath.getBytes(StandardCharsets.US_ASCII);

tomcat10/src/test/java/com/linecorp/armeria/server/tomcat/UnmanagedTomcatServiceTest.java

@@ -26,7 +26,10 @@
 import java.net.Socket;
 import java.nio.charset.StandardCharsets;
 
+import org.apache.catalina.Context;
+import org.apache.catalina.Wrapper;
 import org.apache.catalina.connector.Connector;
+import org.apache.catalina.servlets.WebdavServlet;
 import org.apache.catalina.startup.Tomcat;
 import org.apache.hc.client5.http.classic.methods.HttpGet;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
@@ -46,6 +49,7 @@ class UnmanagedTomcatServiceTest {
 
     private static Tomcat tomcatWithWebApp;
     private static Tomcat tomcatWithoutWebApp;
+    private static Tomcat tomcatWithPropfind;
 
     @RegisterExtension
     static final ServerExtension server = new ServerExtension() {
@@ -66,16 +70,32 @@ protected void configure(ServerBuilder sb) throws Exception {
                                            "tomcat-" + UnmanagedTomcatServiceTest.class.getSimpleName() + "-2");
             assertThat(TomcatUtil.engine(tomcatWithoutWebApp.getService(), "bar")).isNotNull();
 
+            tomcatWithPropfind = new Tomcat();
+            tomcatWithPropfind.setPort(0);
+
+            Context ctx = tomcatWithPropfind.addContext("", "build" + File.separatorChar +
+                                                                               "tomcat-" + UnmanagedTomcatServiceTest.class.getSimpleName() + "-3");
+
+            Wrapper webdavServlet = Tomcat.addServlet(ctx, "webdav", new WebdavServlet());
+            webdavServlet.addInitParameter("readonly", "false");
+            webdavServlet.addInitParameter("listings", "true");
+
+            ctx.addServletMappingDecoded("/*", "webdav");
+            assertThat(TomcatUtil.engine(tomcatWithPropfind.getService(), "foobar")).isNotNull();
+
             // Start the Tomcats.
             tomcatWithWebApp.start();
             tomcatWithoutWebApp.start();
+            tomcatWithPropfind.start();
 
             // Bind them to the Server.
             sb.serviceUnder("/empty/", TomcatService.of(new Connector(), "someHost"))
               .serviceUnder("/some-webapp-nohostname/",
                             TomcatService.of(tomcatWithWebApp.getConnector()))
               .serviceUnder("/no-webapp/", TomcatService.of(tomcatWithoutWebApp))
-              .serviceUnder("/some-webapp/", TomcatService.of(tomcatWithWebApp));
+              .serviceUnder("/some-webapp/", TomcatService.of(tomcatWithWebApp))
+              .serviceUnder("/propfind/", TomcatService.of(tomcatWithPropfind))
+              .additionalAllowedHttpMethods("PROPFIND");
         }
     };
 
@@ -89,6 +109,10 @@ static void destroyTomcat() throws Exception {
             tomcatWithoutWebApp.stop();
             tomcatWithoutWebApp.destroy();
         }
+        if (tomcatWithPropfind != null) {
+            tomcatWithPropfind.stop();
+            tomcatWithPropfind.destroy();
+        }
     }
 
     @Test
@@ -147,4 +171,20 @@ void okWithoutAuthorityHeader() throws Exception {
             }
         }
     }
+
+    @Test
+    void okWithCustomMethod() throws Exception {
+        final int port = server.httpPort();
+        try (Socket s = new Socket(NetUtil.LOCALHOST, port)) {
+            final InputStream in = s.getInputStream();
+            final OutputStream out = s.getOutputStream();
+            out.write(("PROPFIND /propfind/ HTTP/1.1\r\n" +
+                       "Content-Length: 0\r\n" +
+                       "Connection: close\r\n\r\n").getBytes(StandardCharsets.US_ASCII));
+
+            try (BufferedReader br = new BufferedReader(new InputStreamReader(in))) {
+                assertThat(br.readLine()).isEqualTo("HTTP/1.1 200 OK");
+            }
+        }
+    }
 }