那些年踩过的坑

2016-07-27

1. 使用nginx中转时，如后端服务时间过长，导致前段页面返回http的504 gateway timeout错误。解决办法：nginx在转发时增加timeout。
   Example:

       location /weixinYdt {
          proxy_pass http://weixinYdt_server;
          proxy_connect_timeout 500s;
          proxy_read_timeout 500s;
          proxy_send_timeout 500s;
    }
   

2. com.ning.http.client.AsyncHttpClient类的使用

• 可通过AsyncHttpClientConfig设置http client相关参数
• AsyncHttpClient.BoundRequestBuilder设置http请求相关信息
  Example:

public static String postJson(String url, Map<String, String> params,String requestBody) throws IOException, ExecutionException, InterruptedException {
        //设置http请求相关参数
        AsyncHttpClientConfig.Builder configBuilder = new AsyncHttpClientConfig.Builder();
        configBuilder.setRequestTimeout(240 * 1000);//设置timeout时间

        AsyncHttpClient http = new AsyncHttpClient(configBuilder.build());
        AsyncHttpClient.BoundRequestBuilder builder = http.preparePost(url);
        builder.setBodyEncoding(DEFAULT_CHARSET);
        builder.setBody(requestBody);
        builder.setHeader("Content-Type", MediaType.APPLICATION_JSON.toString());
        builder.setHeader("Accept",MediaType.APPLICATION_JSON.toString());
        builder.setRequestTimeout(240 * 1000);
        if (params != null && !params.isEmpty()) {
            Set<String> keys = params.keySet();
            for (String key : keys) {
                builder.addQueryParam(key, params.get(key));
            }
        }

        Future<Response> f = builder.execute();

        String body = f.get().getResponseBody(DEFAULT_CHARSET);
        http.close();
        return body;
    }

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2016-07-20

1. 在出现高并发时，如果数据库是有主键约束，那么需要在发生约束异常时进行处理。