使用core.async通道在clojure中使用http-kit的帖子结果是否合理?

时间:2013-12-12 04:04:59

标签: clojure core.async http-kit

我是clojure的新手,正在编写一个库,将发布结果发送到服务器以获取响应。我通过将响应放在core.async通道上来消耗响应。这是理智还是有更好的方法?

以下是我正在做的事情的高级概述:

(defn my-post-request [channel options]
  (client/post http://www.example.com options
          (fn [{:keys [status headers body error]}] ;; asynchronous handle response
              (go (>! channel body)))))

(defn request-caller [options]
  (let [channel (chan)]
    (my-post-request channel options)
    (json/parse-string (<!! (go (<! channel))))))

以下是我使用的实际代码:https://github.com/gilmaso/btc-trading/blob/master/src/btc_trading/btc_china.clj#L63

它有效,但我很难确认这是否是正确的方法。

1 个答案:

答案 0 :(得分:10)

core.async功能强大,但在协调更复杂的异步性方面却非常有用。如果你总是想阻止回复,我建议使用promise,因为它更简单:

(defn my-post-request [result options]
  (client/post http://www.example.com options
          (fn [{:keys [status headers body error]}] ;; asynchronous handle response
              (deliver result body))))

(defn request-caller [options]
  (let [result (promise)]
    (my-post-request result options)
    ; blocks, waiting for the promise to be delivered
    (json/parse-string @result)))

如果您确实想使用频道,可以稍微清理一下代码。重要的是,您不需要将所有内容都包装在go块中; go对于协调异步性来说是惊人的,但最终,一个频道是一个频道:

(defn my-post-request [channel options]
  (client/post http://www.example.com options
          (fn [{:keys [status headers body error]}] ;; asynchronous handle response
              (put! channel body))))

(defn request-caller [options]
  (let [channel (chan)]
    (my-post-request channel options)
    (json/parse-string (<!! channel))))