This module is heavily based on https://github.com/Masterminds/semver so kudos to Masterminds.
For now only RFC3339 dates are supported
There are two elements to the comparisons. First, a comparison string is a list
of space or comma separated AND comparisons. These are then separated by || (OR)
comparisons. For example, ">= 2020-03-01T00:00:00Z < 2020-04-01T00:00:00Z || >= 2020-05-01T00:00:00Z" is will validate if a date is between 01/03/2020 till 01/04/2020 OR it's after 01/05/2020.
The basic comparisons are:
=: equal!=: not equal>: greater than<: less than>=: greater than or equal to<=: less than or equal to
import "github.com/reflog/dateconstraints"
import "time"
func main(){
date, _ := time.Parse(time.RFC3339, "2020-03-10T00:00:00Z")
c, _ := date_constraints.NewConstraint("> 2020-03-01T00:00:00Z <= 2020-04-01T00:00:00Z")
if c.Check(&date) {
// date is in range!
}
}In addition to testing a date against a constraint, it can be validated against a constraint. When validation fails a slice of errors containing why a date didn't meet the constraint is returned. For example,
c, err := date_constraints.NewConstraint("<= 2020-03-01T00:00:00Z, >= 2020-04-10T00:00:00Z")
if err != nil {
// Handle constraint not being parseable.
}
v, err := time.Parse(time.RFC3339, "2020-03-10T00:00:00Z")
if err != nil {
// Handle date not being parseable.
}
// Validate a date against a constraint.
a, msgs := c.Validate(&v)
// a is false
for _, m := range msgs {
fmt.Println(m)
// Loops over the errors which would read
// "2020-03-10T00:00:00Z is greater than 2020-03-01T00:00:00Z"
// "2020-03-01T00:00:00Z is less than 2020-04-01T00:00:00Z"
}go get github.com/reflog/dateconstraints
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.
Please make sure to update tests as appropriate.