javascript - Node.js `request.get`: store body in variable

Question

I’m new to Node.js, and so sorry for what is probably a dumb question…</p>

Here’s my code:

#!/usr/bin/env coffee --bare

#   3rd party
request  = require('request')
request.defaults({'encoding': 'utf8'})

module.exports.fetchDepartments = fetchDepartments

fetchDepartments = (url) ->
    _body = ''

    getHandler = (error, response, body) -> 
        util.debug "HTTP response code: #{response.statusCode}"

        if error
            util.error error
        else    
            _body = body

    request.get(url, getHandler)
    _body

console.log fetchDepartments('https://ntst.umd.edu/soc/')

The console is printing the call to util.debug(), but it seems that _body remains an empty string.

…How can I store the HTML from the HTTP response?!?

Answer 1

您似乎在请求完成_body 之前返回。

该请求不是同步的，因此您几乎可以肯定要定义一个回调。在纯 JavaScript 中，这将是：

fetchDepartments('https://ntst.umd.edu/soc', function (err, body) {
    console.log(body);
});

它目前正在做的是：

1. 初始化_body为''
2. 创建（但不执行！）getHandler
3. 开始请求
4. 返回（仍然为空）_body
5. 记录（空）_body
6. 稍后：请求完成，调用getHandler
7. getHandler()更新_body

您需要做的是制作fetchDepartments接受回调函数，以便任何代码进程_body都可以等到请求完成。