# Callback function to handle http request

**URL:** <https://discourse.nodered.org/t/callback-function-to-handle-http-request/9686>\
**Category:** Developing Nodes\
**Created:** [2 April 2019 11:44 UTC](https://discourse.nodered.org/t/callback-function-to-handle-http-request/9686 "2019-04-02T11:44:21Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Simo219h](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/simo219h/32/7229_2.png) [@Simo219h](https://discourse.nodered.org/u/Simo219h)\
**Post date:** [2 April 2019 11:44 UTC](https://discourse.nodered.org/t/callback-function-to-handle-http-request/9686/1 "2019-04-02T11:44:21Z")

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Hi,

I am writing a node, which purpose is to forward its input via a HTTP POST request.

I use the node module ['better-sqlite3'](https://github.com/JoshuaWise/better-sqlite3/blob/master/docs/api.md) to sample the input data, with the following columns:

> ID, timestamp, feedname, value, uploadStatus

The uploadStatus column is updated, with a value indicating that the row has been uploaded correctly via the HTTP POST request.

Here I use the ['request module'](https://github.com/request/request) for making the HTTP POST request.

My problem is, when I inject my node with data, everything is fine, except for if I inject some more data rapidly after each other. This results in that the last HTTP POST request callback function was not finished.

```
        node.on('input', function(msg) {    
        
        var time = new Date();
        value = msg.payload;
        timestamp = `${time.getUTCFullYear()}-${time.getUTCMonth()+1}-${time.getUTCDate()} ${time.getUTCHours()}:${time.getUTCMinutes()}:${time.getUTCSeconds()}`;
        uploadStatus = 0;
        uploadCount++;

        //Insert data into sql database, ROW_ID will increment by 1 for each datainput.
        sqliteInsertValue(tableName, timestamp, feedname, value, uploadStatus);
        
        postData();
        });

```

The scenario is that, when the HTTP POST request is ongoing, it is possible to inject some more data, which means the SQL database is newer, than the current one. I want that data to be sent as well. Does anybody have an idea, how to handle that?

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<div class="post-metadata">

**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [8 April 2019 20:31 UTC](https://discourse.nodered.org/t/callback-function-to-handle-http-request/9686/2 "2019-04-08T20:31:24Z")

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> [@Simo219h](#):
>
> The scenario is that, when the HTTP POST request is ongoing, it is possible to inject some more data, which means the SQL database is newer, than the current one. I want that data to be sent as well. Does anybody have an idea, how to handle that?

Not all that clear how you want things to work. But a couple of ideas spring to mind.

- Change the db so it isn't relying on the autoincrement row\_id but uses a fine-grained timestamp as its index. So that you no longer have to worry about clashing rows.
- Implement your db writes as an API with caching so that the relatively slow db write no longer matters.