tm_formatdate
Function
tm_formatdate
converts a timestamp into a different time format.
tm_formatdate(spec, timestamp)
In the Terraform language, timestamps are conventionally represented as strings using RFC 3339 "Date and Time format" syntax. tm_formatdate
requires the timestamp
argument to be a string conforming to this syntax.
Examples
tm_formatdate("DD MMM YYYY hh:mm ZZZ", "2018-01-02T23:12:01Z")
02 Jan 2018 23:12 UTC
tm_formatdate("EEEE, DD-MMM-YY hh:mm:ss ZZZ", "2018-01-02T23:12:01Z")
Tuesday, 02-Jan-18 23:12:01 UTC
tm_formatdate("EEE, DD MMM YYYY hh:mm:ss ZZZ", "2018-01-02T23:12:01-08:00")
Tue, 02 Jan 2018 23:12:01 -0800
tm_formatdate("MMM DD, YYYY", "2018-01-02T23:12:01Z")
Jan 02, 2018
tm_formatdate("HH:mmaa", "2018-01-02T23:12:01Z")
11:12pm
Specification Syntax
The format specification is a string that includes formatting sequences from the following table. This function is intended for producing common machine-oriented timestamp formats such as those defined in RFC822, RFC850, and RFC1123. It is not suitable for truly human-oriented date formatting because it is not locale-aware. In particular, it can produce month and day names only in English.
The specification may contain the following sequences:
Sequence | Result |
---|---|
YYYY | Four (or more) digit year, like "2006". |
YY | The year modulo 100, zero padded to at least two digits, like "06". |
MMMM | English month name unabbreviated, like "January". |
MMM | English month name abbreviated to three letters, like "Jan". |
MM | Month number zero-padded to two digits, like "01" for January. |
M | Month number with no padding, like "1" for January. |
DD | Day of month number zero-padded to two digits, like "02". |
D | Day of month number with no padding, like "2". |
EEEE | English day of week name unabbreviated, like "Monday". |
EEE | English day of week name abbreviated to three letters, like "Mon". |
hh | 24-hour number zero-padded to two digits, like "02". |
h | 24-hour number unpadded, like "2". |
HH | 12-hour number zero-padded to two digits, like "02". |
H | 12-hour number unpadded, like "2". |
AA | Hour AM/PM marker in uppercase, like "AM". |
aa | Hour AM/PM marker in lowercase, like "am". |
mm | Minute within hour zero-padded to two digits, like "05". |
m | Minute within hour unpadded, like "5". |
ss | Second within minute zero-padded to two digits, like "09". |
s | Second within minute, like "9". |
ZZZZZ | Timezone offset with colon separating hours and minutes, like "-08:00". |
ZZZZ | Timezone offset with just sign and digit, like "-0800". |
ZZZ | Like ZZZZ but with a special case "UTC" for UTC. |
Z | Like ZZZZZ but with a special case "Z" for UTC. |
Any non-letter characters, such as punctuation, are reproduced verbatim in the output. To include literal letters in the format string, enclose them in single quotes '
. To include a literal quote, escape it by doubling the quotes.
tm_formatdate("h'h'mm", "2018-01-02T23:12:01-08:00")
23h12
tm_formatdate("H 'o''clock'", "2018-01-02T23:12:01-08:00")
11 o'clock
This format specification syntax is intended to make it easy for a reader to guess which format will result even if they are not experts on the syntax. Therefore there are no predefined shorthands for common formats, but format strings for various RFC-specified formats are given below to be copied into your configuration as needed:
- RFC 822 and RFC RFC 2822:
"DD MMM YYYY hh:mm ZZZ"
- RFC 850:
"EEEE, DD-MMM-YY hh:mm:ss ZZZ"
- RFC 1123:
"EEE, DD MMM YYYY hh:mm:ss ZZZ"
- RFC 3339:
"YYYY-MM-DD'T'hh:mm:ssZ"
(but this is also the input format, so such a conversion is redundant.)
Related Functions
tm_format
is a more general formatting function for arbitrary data.tm_timestamp
returns the current date and time in a format suitable for input toformatdate
.