Parsing date string in Go

Question

I tried parsing the date string  2014-09-12T11 45 26 371Z  in Go    Code  layout     2014-09-12T11 45 26 371Z  str     2014-11-12T11 45 26 371Z  t  err    time Parse layout   str    I got this error      parsing time  2014-11-12T11 47 39 489Z   month out of range   How can I parse this date string

User · Answer

Use the exact layout numbers described here and a nice blogpost here.

so:

layout := "2006-01-02T15:04:05.000Z"
str := "2014-11-12T11:45:26.371Z"
t, err := time.Parse(layout, str)

if err != nil {
    fmt.Println(err)
}
fmt.Println(t)

gives:

>> 2014-11-12 11:45:26.371 +0000 UTC

I know. Mind boggling. Also caught me first time. Go just doesn't use an abstract syntax for datetime components (YYYY-MM-DD), but these exact numbers (~~I think the time of the first commit of go~~ Nope, according to this. Does anyone know?).

User · Answer

This might be super late  but this is for people that might stumble on this problem and might want to use external package for parsing date string   I ve tried looking for a libraries and I found this one   https   github com araddon dateparse  Example from the README   package main  import        flag       fmt       time        github com apcera termtables       github com araddon dateparse     var examples     string       May 8  2009 5 57 51 PM        Mon Jan  2 15 04 05 2006        Mon Jan  2 15 04 05 MST 2006        Mon Jan 02 15 04 05 -0700 2006        Monday  02-Jan-06 15 04 05 MST        Mon  02 Jan 2006 15 04 05 MST        Tue  11 Jul 2017 16 28 13  0200  CEST         Mon  02 Jan 2006 15 04 05 -0700        Thu  4 Jan 2018 17 53 36  0000        Mon Aug 10 15 44 11 UTC 0100 2015        Fri Jul 03 2015 18 04 07 GMT 0100  GMT Daylight Time         12 Feb 2006  19 17        12 Feb 2006 19 17        03 February 2013        2013-Feb-03            mm dd yy      3 31 2014        03 31 2014        08 21 71        8 1 71        4 8 2014 22 05        04 08 2014 22 05        4 8 14 22 05        04 2 2014 03 00 51        8 8 1965 12 00 00 AM        8 8 1965 01 00 01 PM        8 8 1965 01 00 PM        8 8 1965 1 00 PM        8 8 1965 12 00 AM        4 02 2014 03 00 51        03 19 2012 10 11 59        03 19 2012 10 11 59 3186369          yyyy mm dd      2014 3 31        2014 03 31        2014 4 8 22 05        2014 04 08 22 05        2014 04 2 03 00 51        2014 4 02 03 00 51        2012 03 19 10 11 59        2012 03 19 10 11 59 3186369          Chinese      2014 04 08             yyyy-mm-ddThh      2006-01-02T15 04 05 0000        2009-08-12T22 15 09-07 00        2009-08-12T22 15 09        2009-08-12T22 15 09Z            yyyy-mm-dd hh mm ss      2014-04-26 17 24 37 3186369        2012-08-03 18 31 59 257000000        2014-04-26 17 24 37 123        2013-04-01 22 43        2013-04-01 22 43 22        2014-12-16 06 20 00 UTC        2014-12-16 06 20 00 GMT        2014-04-26 05 24 37 PM        2014-04-26 13 13 43  0800        2014-04-26 13 13 44  09 00        2012-08-03 18 31 59 257000000  0000 UTC        2015-09-30 18 48 56 35272715  0000 UTC        2015-02-18 00 12 00  0000 GMT        2015-02-18 00 12 00  0000 UTC        2017-07-19 03 21 51 00 00        2014-04-26        2014-04        2014        2014-05-11 08 20 13 787          mm dd yy      3 31 2014        03 31 2014        08 21 71           yyyymmdd and similar      20140601          unix seconds  ms      1332151919        1384216367189      var       timezone         func main         flag StringVar  amp timezone   timezone    UTC    Timezone aka  America Los Angeles  formatted time-zone       flag Parse        if timezone                    NOTE   This is very  very important to understand            time-parsing in go         loc  err    time LoadLocation timezone          if err    nil               panic err Error                      time Local   loc            table    termtables CreateTable        table AddHeaders  Input    Parsed  and Output as  v       for    dateExample    range examples           t  err    dateparse ParseLocal dateExample          if err    nil               panic err Error                      table AddRow dateExample  fmt Sprintf   v   t             fmt Println table Render

User · Answer

This is rather late to the party  and not really saying anything that hasn t been already said in one form or another  mostly through links above  but I wanted to give a TL DR recap to those with less attention span   The date and time of the go format string is very important  It s how Go knows which field is which  They are generally 1-9 left to right as follows    January   Jan   january   jan   01    1  etc  are for month 02    2 are for day of month 15   03    3   PM   P   pm  p are for hour  amp  meridian  3pm  04    4 are for minutes 05    5 are for seconds 2006   06 are for year -0700   07 00   MST are for timezone  999999999    000000000 etc are for partial seconds  I think the distinction is if trailing zeros are removed  Mon   Monday are day of the week  which 01-02-2006 actually was     So  Don t write  01-05-15  as your date format  unless you want  Month-Second-Hour        again  this was basically a summary of above

User · Answer

For those of you out there that are encountering this  use the time RFC3339 versus the string constant of  quot 2006-01-02T15 04 05 000Z quot   And here is the reason why  regDate     quot 2007-10-09T22 50 01 23Z quot   layout1     quot 2006-01-02T15 04 05 000Z quot  t1  err    time Parse layout1  regDate   if err    nil       fmt Println  quot Static format doesn t work quot     else       fmt Println t1     layout2    time RFC3339 t2  err    time Parse layout2  regDate   if err    nil       fmt Println  quot RFC format doesn t work quot      You shouldn t see this at all   else       fmt Println t2     This will produce the following result  Static format doesn t work 2007-10-09 22 50 01 23  0000 UTC  Here is the Playground Link

User · Answer

As answered but to save typing out  2006-01-02T15 04 05 000Z  for the layout  you could use the package s constant RFC3339   str     2014-11-12T11 45 26 371Z  t  err    time Parse time RFC3339  str   if err    nil       fmt Println err    fmt Println t    https   play golang org p Dgu2ZvHwTh

User · Answer

If you have worked with time date formatting parsing in other languages you might have noticed that the other languages use special placeholders for time date formatting  For eg ruby language uses   d for day  Y for year   etc  Golang  instead of using codes such as above  uses date and time format placeholders that look like date and time only  Go uses standard time  which is   Mon Jan 2 15 04 05 MST 2006   MST is GMT-0700  or  01 02 03 04 05PM  06 -0700   So if you notice Go uses  01 for the day of the month  02 for the month 03 for hours  04 for minutes 05 for second and so on   Therefore for example for parsing 2020-01-29  layout string should be 06-01-02 or 2006-01-02   You can refer to the full placeholder layout table at this link - https   golangbyexample com parse-time-in-golang

User · Answer

The layout to use is indeed  2006-01-02T15 04 05 000Z  described in RickyA s answer  It isn t  the time of the first commit of go   but rather a mnemonic way to remember said layout  See pkg time      The reference time used in the layouts is    Mon Jan 2 15 04 05 MST 2006      which is Unix time 1136239445    Since MST is GMT-0700  the reference time can be thought of as    01 02 03 04 05PM  06 -0700    1 2 3 4 5 6 7  provided you remember that 1 is for the month  and 2 for the day  which is not easy for an European like myself  used to the day-month date format   As illustrated in  time parse   why does golang parses the time incorrectly    that layout  using 1 2 3 4 5 6 7  must be respected exactly

User · Answer

I will suggest using time RFC3339 constant from time package  You can check other constants from time package   https   golang org pkg time  pkg-constants  package main  import        fmt       time     func main         fmt Println  Time parsing        dateString     2014-11-12T11 45 26 371Z      time1  err    time Parse time RFC3339 dateString       if err  nil       fmt Println  Error while parsing date     err             fmt Println time1

[date] Parsing date string in Go

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