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android – 如何使用OKHttp进行改装,在离线时使用缓存数据

我想要与OkHttp改装使用缓存时是没有互联网.

我准备好OkHttpClient,如下所示:

RestAdapter.Builder builder= new RestAdapter.Builder()
       .setRequestInterceptor(new RequestInterceptor() {
            @Override
            public void intercept(RequestFacade request) {
                request.addHeader("Accept", "application/json;versions=1");
                if (MyApplicationUtils.isNetworkAvaliable(context)) {
                    int maxAge = 60; // read from cache for 1 minute
                    request.addHeader("Cache-Control", "public, max-age=" + maxAge);
                } else {
                    int maxStale = 60 * 60 * 24 * 28; // tolerate 4-weeks stale
                    request.addHeader("Cache-Control", 
                        "public, only-if-cached, max-stale=" + maxStale);
                }
            }
    });

并设置缓存如下所示:

Cache cache = null;
    try {
        cache = new Cache(httpCacheDirectory, 10 * 1024 * 1024);
    } catch (IOException e) {
        Log.e("OKHttp", "Could not create http cache", e);
    }

    OkHttpClient okHttpClient = new OkHttpClient();
    if (cache != null) {
        okHttpClient.setCache(cache);
    }

我检查了根设备,在缓存目录中保存文件与“响应头”和Gzip文件.

但是我在离线时没有得到改装缓存的正确答案,尽管在GZip文件中是我的正确答案.那么如何使Retrofit可以读取GZip文件,他如何知道应该是哪个文件(因为我有几个文件与其他响应)?

我公司里有simlar问题:)

问题出在服务器端.在serwer答复我有:

Pragma: no-cache

所以当我删除这一切都开始工作.在我删除之前,我得到所有的时间这样的例外:504不满意的请求(only-if-cached)

好的,我的身边如何执行.

OkHttpClient okHttpClient = new OkHttpClient();

    File httpCacheDirectory = new File(appContext.getCacheDir(), "responses");

    Cache cache = new Cache(httpCacheDirectory, maxSizeInBytes);
    okHttpClient.setCache(cache);

    OkClient okClient = new OkClient(okHttpClient);

    RestAdapter.Builder builder = new RestAdapter.Builder();
    builder.setEndpoint(endpoint);
    builder.setClient(okClient);

如果您在测试中遇到问题(服务器或应用程序).您可以使用这样的功能来设置从服务器接收的头文件.

private static final Interceptor REWRITE_CACHE_CONTROL_INTERCEPTOR = new Interceptor() {
    @Override
    public Response intercept(Chain chain) throws IOException {
        Response originalResponse = chain.proceed(chain.request());
        return originalResponse.newBuilder()
                               .removeHeader("Pragma")
                               .header("Cache-Control",
                                       String.format("max-age=%d", 60))
                               .build();
    }
};

并添加它:

okHttpClient.networkInterceptors().add(REWRITE_CACHE_CONTROL_INTERCEPTOR);

感谢你,因为你可以看到我能够删除Pragma:无缓存标头的测试时间.

另外我建议你阅读关于Cache-Control标题:

max-age , max-stale

其他有用的链接:

List of HTTP header fields

Cache controll

Another sample code

http://stackoverflow.com/questions/31321963/how-retrofit-with-okhttp-use-cache-data-when-offline

原文  https://codeday.me/bug/20181015/288805.html
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