How do you validate a string representing a local date in malli?

I'm trying to use https://github.com/metosin/malli?tab=readme-ov-file#malliexperimentaltime

Here is what I have

(ns foobar.core
  (:require [malli.core :as m]
            [malli.registry :as mr]
            [malli.experimental.time :as met]))

;; This should add the malli.experimental.time schemas
(mr/set-default-registry!
  (mr/composite-registry
    (m/default-schemas)
    (met/schemas)))

So, I would expect one of those things to be truthy, but none is:

(m/validate :time/local-date "2024-01-01")
(m/validate [:time/local-date] "2024-01-01")
(m/validate [:time/local-date {:pattern "yyyy-mm-dd"}] "2024-01-01")
(m/validate [:time/local-date {:pattern "yyyy-MM-dd"}] "2024-01-01")
(m/validate [:time/local-date {:pattern "YYYY-MM-DD"}] "2024-01-01")

What am I missing here ?

The doc also mentions a "transformation" feature, is that required here ? https://github.com/metosin/malli?tab=readme-ov-file#transformation---malliexperimentaltimetransform

Solution

Thanks to @gwang-jim-kim for the help, but I found at what I was missing:

I was confusing the role of m/validate, m/decode and m/coerce
- m/validate check that a value conforms to a schema
- m/decode will use a transformer to turn a value into something conforming to the schema, but silently fail
- m/coerce will do the same, but raise
In my case, I want to turn the input string into a date, so I was needing m/coerce
There are already built-in transformers to pass to m/coerce in the malli.experimental.time.transformer namespace
However, for some reason, my project was depending on org.clojure/clojure "1.10.1", and this caused an error when loading the workspace (because math was not available.) (This is fixed by depending on more recent version (eg "1.11.1"))
Also, I was using the wrong parsing pattern sometimes :facepalm:...

So, in the end, this does what I want:

(ns flight.core
  (:require [malli.core :as m]
            [malli.registry :as mr]
            [malli.experimental.time :as met]
            [malli.experimental.time.transform :as mett]))

(mr/set-default-registry!
  (mr/composite-registry
    (m/default-schemas)
    (met/schemas)))

(def schema [:time/local-date {:pattern "yyyy-MM-dd"}] )

(m/validate schema "2024-01-01") ;;=> false, the string is not a LocalDate 

(m/coerce schema "2024-01-01" mett/time-transformer) ;;=> this returns a java.time.LocalDate

(m/decode schema "2024-01-01x" mett/time-transformer) ;;=> this returns the string "2024-01-01x" because decode silently ignores transformation that raise error

(m/coerce schema "2024-01-01x" mett/time-transformer) ;;=> this raises an error

(m/validate schema (m/decode schema "2024-01-01x" mett/time-transformer)) ;;=> this returns false

(m/validate schema (m/decode schema "2024-01-01" mett/time-transformer)) ;;=> this returns true