CookiesHolder.java

/*
 * Copyright 2015 Netflix, Inc.
 *
 * 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.reactivex.netty.protocol.http;

import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.cookie.ClientCookieDecoder;
import io.netty.handler.codec.http.cookie.Cookie;
import io.netty.handler.codec.http.cookie.ServerCookieDecoder;
import io.netty.util.AsciiString;

import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import static io.netty.handler.codec.http.HttpHeaderNames.*;
/**
 * A holder of cookies parsed from the Http headers.
 */
public class CookiesHolder {

    private final HttpHeaders nettyHeaders;
    private final AsciiString cookiesHeaderName;
    private final boolean isClientDecoder;
    private Map<String, Set<Cookie>> allCookies;
    private boolean cookiesParsed;

    private CookiesHolder(HttpHeaders nettyHeaders, AsciiString cookiesHeaderName, boolean isClientDecoder) {
        this.nettyHeaders = nettyHeaders;
        this.cookiesHeaderName = cookiesHeaderName;
        this.isClientDecoder = isClientDecoder;
        allCookies = Collections.emptyMap();
    }

    public Map<String, Set<Cookie>> getAllCookies() {
        return _parseIfNeededAndGet();
    }

    public static CookiesHolder newClientResponseHolder(HttpHeaders headers) {
        return new CookiesHolder(headers, SET_COOKIE, true);
    }

    public static CookiesHolder newServerRequestHolder(HttpHeaders headers) {
        return new CookiesHolder(headers, COOKIE, false);
    }

    private synchronized Map<String, Set<Cookie>> _parseIfNeededAndGet() {
        if (cookiesParsed) { // This method is synchronized, a memory barrier for this variable to be refreshed.
            return allCookies;
        }
        List<String> allCookieHeaders = nettyHeaders.getAll(cookiesHeaderName);
        Map<String, Set<Cookie>> cookies = new HashMap<>();
        for (String aCookieHeader : allCookieHeaders) {
            Set<Cookie> decode;
            if (isClientDecoder) {
                Cookie decoded = ClientCookieDecoder.STRICT.decode(aCookieHeader);
                Set<Cookie> existingCookiesOfName = cookies.get(decoded.name());
                if (null == existingCookiesOfName) {
                    existingCookiesOfName = new HashSet<>();
                    cookies.put(decoded.name(), existingCookiesOfName);
                }
                existingCookiesOfName.add(decoded);
            } else {
                decode = ServerCookieDecoder.STRICT.decode(aCookieHeader);
                for (Cookie cookie : decode) {
                    Set<Cookie> existingCookiesOfName = cookies.get(cookie.name());
                    if (null == existingCookiesOfName) {
                        existingCookiesOfName = new HashSet<>();
                        cookies.put(cookie.name(), existingCookiesOfName);
                    }
                    existingCookiesOfName.add(cookie);
                }
            }
        }
        allCookies = Collections.unmodifiableMap(cookies);
        cookiesParsed = true;
        return allCookies;
    }
}