Terraform
timecmp Function
timecmp
compares two timestamps and returns a number that represents the
ordering of the instants those timestamps represent.
timecmp(timestamp_a, timestamp_b)
Condition | Return Value |
---|---|
timestamp_a is before timestamp_b | -1 |
timestamp_a is the same instant as timestamp_b | 0 |
timestamp_a is after timestamp_b | 1 |
When comparing the timestamps, timecmp
takes into account the UTC offsets
given in each timestamp. For example, 06:00:00+0200
and 04:00:00Z
are
the same instant after taking into account the +0200
offset on the first
timestamp.
In the Terraform language, timestamps are conventionally represented as
strings using RFC 3339
"Date and Time format" syntax. timecmp
requires the its two arguments to
both be strings conforming to this syntax.
Examples
> timecmp("2017-11-22T00:00:00Z", "2017-11-22T00:00:00Z")
0
> timecmp("2017-11-22T00:00:00Z", "2017-11-22T01:00:00Z")
-1
> timecmp("2017-11-22T01:00:00Z", "2017-11-22T00:00:00Z")
1
> timecmp("2017-11-22T01:00:00Z", "2017-11-22T00:00:00-01:00")
0
The timecmp
function is suitable for validations that verify that a specified timestamp is within a particular range. Refer to Validating your configuration to learn more about validating your configuration.
For example, the following resource postcondition would raise an error if a TLS certificate (or other expiring object) expires sooner than 30 days from the time of the "apply" step:
lifecycle {
postcondition {
condition = timecmp(timestamp(), timeadd(self.expiration_timestamp, "-720h")) < 0
error_message = "Certificate will expire in less than 30 days."
}
}