org.springframework.web.socket.server.RequestUpgradeStrategy.java Source code

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Here is the source code for org.springframework.web.socket.server.RequestUpgradeStrategy.java

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/*
 * Copyright 2002-2017 the original author or authors.
 *
 * 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
 *
 *      https://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 org.springframework.web.socket.server;

import java.security.Principal;
import java.util.List;
import java.util.Map;

import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.lang.Nullable;
import org.springframework.web.socket.WebSocketExtension;
import org.springframework.web.socket.WebSocketHandler;

/**
 * A server-specific strategy for performing the actual upgrade to a WebSocket exchange.
 *
 * @author Rossen Stoyanchev
 * @since 4.0
 */
public interface RequestUpgradeStrategy {

    /**
     * Return the supported WebSocket protocol versions.
     */
    String[] getSupportedVersions();

    /**
     * Return the WebSocket protocol extensions supported by the underlying WebSocket server.
     */
    List<WebSocketExtension> getSupportedExtensions(ServerHttpRequest request);

    /**
     * Perform runtime specific steps to complete the upgrade. Invoked after successful
     * negotiation of the handshake request.
     * @param request the current request
     * @param response the current response
     * @param selectedProtocol the selected sub-protocol, if any
     * @param selectedExtensions the selected WebSocket protocol extensions
     * @param user the user to associate with the WebSocket session
     * @param wsHandler the handler for WebSocket messages
     * @param attributes handshake request specific attributes to be set on the WebSocket
     * session via {@link org.springframework.web.socket.server.HandshakeInterceptor} and
     * thus made available to the {@link org.springframework.web.socket.WebSocketHandler}
     * @throws HandshakeFailureException thrown when handshake processing failed to
     * complete due to an internal, unrecoverable error, i.e. a server error as
     * opposed to a failure to successfully negotiate the requirements of the
     * handshake request.
     */
    void upgrade(ServerHttpRequest request, ServerHttpResponse response, @Nullable String selectedProtocol,
            List<WebSocketExtension> selectedExtensions, @Nullable Principal user, WebSocketHandler wsHandler,
            Map<String, Object> attributes) throws HandshakeFailureException;

}