Question

我想用littleproxy缓存静态文件。所以我创建了HashMap，其中包含uri的键和响应体的值。这里是java代码：

private static Map<String, FullHttpResponse> cache = new HashMap<>();

private static HttpFiltersSource getHttpFiltersSource() {
    return new HttpFiltersSourceAdapter() {
            @Override
            public int getMaximumResponseBufferSizeInBytes() {
                return 10 * 1024 * 1024;
            }

        public HttpFilters filterRequest(HttpRequest originalRequest, ChannelHandlerContext ctx) {
            return new HttpFiltersAdapter(originalRequest) {
                @Override
                public HttpResponse clientToProxyRequest(HttpObject httpObject) {

                    if (httpObject instanceof HttpRequest) {
                        HttpRequest request = (HttpRequest) httpObject;
                        String requestUri = request.getUri();

                        if(requestUri.matches(".*[./]png.*$") ||
                                requestUri.matches(".*[./]jpg.*$") ||
                                requestUri.matches(".*[./]jpeg.*$") ||
                                requestUri.matches(".*[./]woff2.*$") ||
                                requestUri.matches(".*[./]js.*$") ) {
                            if (cache.containsKey(requestUri)) {
                                System.out.println("GOT FROM CACHE " + requestUri);

                                return cache.get(requestUri);
                            }
                        }
                    }

                    return null;
                }

                @Override
                public HttpObject serverToProxyResponse(HttpObject httpObject) {
                    if (httpObject instanceof FullHttpResponse) {
                        FullHttpResponse response = (FullHttpResponse) httpObject;
                        String requestUri = originalRequest.getUri();

                            if(requestUri.matches(".*[./]png.*$") ||
                                    requestUri.matches(".*[./]jpg.*$") ||
                                    requestUri.matches(".*[./]jpeg.*$") ||
                                    requestUri.matches(".*[./]woff2.*$") ||
                                    requestUri.matches(".*[./]js.*$") ) {
                                cache.put(requestUri, response.retain());
                                System.out.println("ADDED TO CACHE " + requestUri);
                            }
                    }

                    return httpObject;
                }
            };
        }
    };
}

但是Map中的响应有问题。当浏览器首先到达静态文件时，控制台中会出现一条调试消息：ADDED TO CACHE。当浏览器第二次到达静态文件时，会显示一条消息：＆＃34; GOT FROM CACHE＆＃34;，但浏览器会永远等待响应。

什么是从服务器保存和存储响应的正确方法，并在时间到来时将其返回给客户端？

Answer 1

我认为你还需要复制FullHttpResponse以确保你有正确的作者/读者索引。

cache.put(requestUri, response.duplicate().retain());

和

return cache.get(requestUri).duplicate();

还要确保在从缓存中删除内容后调用release()。

如何用littleproxy / netty缓存流量？

1 个答案: