Databases
StackOverflow2013
Postsdbo
POHow to execute http requests strictly one by one in node.js?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to execute http requests strictly one by one in node.js?
    primarykey
    data
    text
    <p>So, I have an array of some values. I'd like to send these values to www.example.com. I have to send only one value per request.</p> <p>I am using for this task http.request in node.js:</p> <pre><code>var myArr = [1,2,3,4,5,6,7,8,9,10,11,12]; function requestSender(data, callback) { var post = querystring.stringify({ data: data }); var options = { hostname: 'www.example.com', port: 80, path: '/upload', method: 'POST' }; var req = https.request(options, function(res) { res.setEncoding('utf-8'); res.on('data', function(data) { callback(); }); }); req.on('error', function(e) { console.log('problem with request: ' + e.message); }); req.write(post); req.end(); } </code></pre> <p>To send requests one by one I am using function, that takes an array of functions and recursively adds next function as the callback to previous:</p> <pre><code>function stack(arr) { var newArr = arr.slice(1); arr[0](function() { if (typeof newArr[0] == 'function') stack(newArr); }); } </code></pre> <p>And to compile all this staff into one, I am using the following code:</p> <pre><code>var functionsArr = []; for (i in myArr) { functionsArr.push(function(callback) { var value = myArr[i]; requestSender(value, callback); }); }; stack(functionsArr); </code></pre> <p>But actually, this does not work: all requests are sent in 1 millisecond, and after that callbacks are listening while responses are recieved. But it should not! I have put <em>callback()</em> in http.request(options, <strong>callback</strong>)!! How does it happen?</p> <p>So my questions are: 1) How can I send http requests strictly one by one in node.js? 2) Why does not my solution work?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USWunsch Punsch
    1. USWunsch Punsch
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. COWhat do you mean by "strictly one by one"? I took it as meaning that you don't want to start a new one until the first one has finished - but then you also wrote "as fast as possible" -- which to me indicates that you do want to send them all at once, since that would be as fast as possible. Can you edit/clarify in what way your code is not working as you expect.
      singulars
      1. POHow to execute http requests strictly one by one in node.js?
      1. USarnorhs
    2. COYou have got the meaning of 'strictly one by one' as I wanted to. "As fast as possible" means not to use *setTimeout()* or something like that. But you are right, I should better remove "as fast as possible" thing from the post
      singulars
      1. POHow to execute http requests strictly one by one in node.js?
      1. USWunsch Punsch
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload