Use of 'toLocaleString' when converting values about json-2-csv

[mrodrig]

Per #66 this was causing an issue that I didn't see in my dev environment that was causing the number 1000 to be converted to 1,000 which was not of the proper form. I reverted the changes and will look to see if there is a better way to implement this without breaking the functionality.

Edit: Reverted in 2.0.18; Unpublished 2.0.13 through 2.0.17 which had this change.

[mrodrig]

I hadn't thought about that, but it definitely makes more sense to use value.toLocaleString() than value.toString() like you mentioned. I'll definitely take a look at implementing this. Thanks!

[mrodrig]

I was working on implementing this, but noticed that it might cause the csv2json function to incorrectly convert data back to JSON. In particular, if json2csv converts a float (ie. 3.14) to 3,14, then it won't be as easy to convert back to a float: parseFloat('3,14'); // returns 3 since it doesn't take a locale.

I suppose this is fine since all values are treated as strings in csv2json though.

[mrodrig]

I believe this should be all set in version 2.0.13. The option to set is: option.LOCALE. I tried testing it out and despite setting the locale to a variety of the values on MDN .toLocaleString() documentation page, I didn't see any difference but that could just be the environment configuration that I have.

Please let me know if you have any issues with it. Thanks again!

[datuary-jmartinez]

Hello Mike:

I was working on implementing this, but noticed that it might cause the csv2json function to incorrectly convert data back to JSON. In particular, if json2csv converts a float (ie. 3.14) to 3,14, then it won't be as easy to convert back to a float: parseFloat('3,14'); // returns 3 since it doesn't take a locale.

I suppose this is fine since all values are treated as strings in csv2json though.

I think that before converting from CSV (string) to JSON (float) you should check option.LOCALE. If no option provided or it is similar to US format, nothing has to be done and parseFloat('3.14') must work properly. Otherwise, parseFloat(value.replace(',','.')) should be execute to replace string for a valid format.

Going further, I think you could always replace commas with points before parsing because if you have '3.14' you do nothing and if you have '3,14' you convert it to proper format.

You can also ignore .toLocaleString and allow user to declare his own decimal separator and thousand separator. User has now the responsibility and flexibility to choose whatever he needs.

Regards

[datuary-jmartinez]

Hello again:

I have just executed this code in Javascript console in Chrome:

var pi = 3.14;
undefined
console.log(pi.toString());
3.14
undefined
console.log(pi.toLocaleString('es-ES'));
3,14
undefined 

It works as expected. I don't think it has something to do with your environment because you explicitly indicate what locale you want.

Regards

[mrodrig]

Thanks @jmartinez-emagina! I will take a look at configuring csv2json to perform those checks. I see the same behavior in the Chrome console, but when I tried it in Node on my Cloud9 development machine, it completely ignores the locale provided. I believe that is due to Cloud9's environment configuration, but I would imagine that the option (now available in version 2.0.13 with options.locale) should work as expected. Thanks!

Output from Node on Cloud9 for reference:

> var pi = 3.14
undefined
> console.log(pi.toString())
3.14
undefined
> console.log(pi.toLocaleString('es-ES'))
3.14
undefined

[mrodrig]

Going to close this out until I have a chance to convert the module to force values to be wrapped in quotes.

[meelash]

I have another use case for this, wondering if this is still a possibility to get implemented, and/or if there is a better way currently to accomplish what I'm seeking.
By default datetimes will be converted to UTC when creating a csv, since that is what Date.prototype.toString() does. Generally, I'm guessing this would not be desired behavior.

Example:

{
  startTime: new Date('2020-03-05 16:34:39')
}

If my local timezone is EST, json2csv output will be:

startTime
'2020-03-05 21:34:39'

Is there a way I can (even a temporary fix) get json2csv to use toLocaleString or any other way to get dates to convert to a string in the local timezone?

[mrodrig]

Added the useLocaleFormat option, which when set to true will cause the module to use toLocaleString() instead of toString(). This new option is published in 3.7.0 and should be available on NPM.