UTC Time string conversion problem

[aratom]

Hey there!

I'm using the HTTP agent to get the headers of a file, like curl -I https://example.com which works fine. The answer is successfully converted to JSON.

My idea was using a preprocessing step to extract the "Last-Modified" from JSON. Works fine.

Where I fail is using JS to convert the received string like

Thu, 26 Jan 2023 11:12:13 GMT

I used

return Date.parse(value)

, which works awesome with my dev environment in VS Code.

After heavy searching and testing I figured that with the given duktape implementation Date.now() is implemented but the Date.parse() is not fully implemented, because I can convert a time in the format of

YYYY-MM-DDTHH:mm:ss.sssZ

I was wondering whether someone had an idea on how to solve this problem or some way around it.

Thank you!
Thomas

[cyber]

https://javascript.info/date

says that

Date.parse from a string


The method Date.parse(str) can read a date from a string.

The string format should be: YYYY-MM-DDTHH:mm:ss.sssZ, where:

• YYYY-MM-DD – is the date: year-month-day.
• The character "T" is used as the delimiter.
• HH:mm:ss.sss – is the time: hours, minutes, seconds and milliseconds.
• The optional 'Z' part denotes the time zone in the format +-hh:mm. A single letter Z would mean UTC+0.

So, why do you think, that it should be able to read any given format? Maybe your VSCode has some fancy plugin there?

[aratom]

thank you cyber for the quick reply.

It seems that depending on the implementation this functionality is available or not.

Luckily, after uncounted hours of research, I found this

https://stackoverflow.com/a/22186399

var string = "Tue, 04 Mar 2014 21:35:31 GMT"
var parts = string.match(/(\w*), (\d{2}) (\w*) (\d{4}) (\d{2})\\d{2})\\d{2})/);
var month = "JanFebMarAprMayJunJulAugSepOctNovDec".indexOf (par ts[3]) / 3 + 1
td = new Date(parts[4], month, parts[2],parts[5], parts[6], parts[7])
td.getTime()

For me this works, beautiful code is something else. Interestingly I had some trouble with websites answering with "Last-Modified" and some with "last-modified" therefore this weird check.

var json = JSON.parse(value)

var string = "Tue, 01 Jan 1970 10:00:00 GMT"

if(JSON.stringify(json.header["Last-Modified"]))
    string = JSON.stringify(json.header["Last-Modified"])
else if (JSON.stringify(json.header["last-modified"]))
    string = JSON.stringify(json.header["last-modified"])
else
    return 0;

// https://stackoverflow.com/a/22186399
// var string = value;
var parts = string.match(/(\w*), (\d{2}) (\w*) (\d{4}) (\d{2})\:(\d{2})\:(\d{2})/);
var month = "JanFebMarAprMayJunJulAugSepOctNovDec".indexOf(parts[3]) / 3 + 1

var date = new Date(parts[4], month, parts[2],parts[5], parts[6], parts[7])
return (Date.parse(date)/1000)​