peri learns to coerce

New peri release out. Four things landed, all stolen shamelessly from malli and zod, which is what inspiration means if you are honest about it.

The big one: coercion. HTTP params are all strings, and until now peri would just reject them. No more.

defschema :params, %{
  page: {:coerce, :string, {:integer, {:gte, 1}}},
  admin: {:coerce, :string, :boolean}
}

MySchemas.params(%{"page" => "2", "admin" => "true"})
#=> {:ok, %{page: 2, admin: true}}

There is Peri.encode/3 too, which runs the schema backwards, so decode and encode round-trip. Very codec. Very symmetric. I am pleased.

Also: Peri.Error.humanize/1 gives you %{email: ["is required"]} instead of a struct tree, missing required keys now come with a “did you mean” (you typed emial, we have all typed emial), schemas compose with merge/select/except, and Peri.Phoenix.to_form/3 feeds a schema straight into LiveView forms without Ecto anywhere in sight.

That is it. Go validate something.