/// <summary>
/// 把请求的报文和返回的报文保存到日志中
/// 用法：
/// Gloab中 GlobalConfiguration.Configuration.MessageHandlers.Add(new CustomMessageHandler());
/// </summary>
/// <param name="request">请求信息</param>
/// <param name="cancellationToken">取消操作的标记</param>
/// <returns></returns>
protected override Task <HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
string md5 = null;
//请求的内容作为缓存key
if (request.Content != null)
{
string reqStr;
string method = request.Method.Method;
if (method.ToLower().Equals("post"))
{
string uri = request.RequestUri.ToString();
string body = request.Content.ReadAsStringAsync().Result;
reqStr = string.Format("{0}{1}", uri, body);
}
else
{
reqStr = request.RequestUri.ToString();
}
md5 = Md5Utils.GetMD5(reqStr);
}
//是否有缓存
var result = CacheFactory.GetCacheManage().Get <string>(md5);
if (!string.IsNullOrEmpty(result))
{
// 创建响应。
var response = new HttpResponseMessage(HttpStatusCode.OK)
{
Content = new StringContent(result)
};
// Note: TaskCompletionSource creates a task that does not contain a delegate.
// 注：TaskCompletionSource创建一个不含委托的任务。
var tsc = new TaskCompletionSource <HttpResponseMessage>();
tsc.SetResult(response); // Also sets the task state to "RanToCompletion"
// 也将此任务设置成“RanToCompletion（已完成）”
return(tsc.Task);
}
else
{ //如果缓存没有命中，则继续接口查询
return(base.SendAsync(request, cancellationToken).ContinueWith(
task =>
{
//把返回的json放到缓存
string json = task.Result.Content.ReadAsStringAsync().Result;
//缓存5分钟
CacheFactory.GetCacheManage().Set(md5, json, new TimeSpan(0, 0, 5));
return task.Result;
}, cancellationToken));
}
}