This module provides validators for Times.

You can use the following checks:

• :is to check if a Time is exactly some Time. You can also provide a :delta option (in seconds) to specify a delta around which the Time is still considered identical.
• :before to check if a Time is before some Time
• :after to check if a Time is after some Time

You can also combine the given checks for complex checks. Errors won't be stacked though, the first error encountered will be returned and subsequent checks will be skipped. If you want to check everything at once, you'll need to call this validator multiple times.

Also, instead of providing a Time, you can also provide some special atoms:

• :utc_now will compare the given Time with the Time at runtime, by calling Time.utc_now().

Example:

iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start)
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [], data: %{}, valid?: true>

# Using :is to ensure a time is identical to another time
iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, is: ~T[12:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [], data: %{}, valid?: true>

iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, is: ~T[13:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [meeting_start: {"should be %{is}.", [validation: :time, kind: :is]}], data: %{}, valid?: false>

# Using :is with :delta to ensure a time is near another another time
iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, is: ~T[12:15:01], delta: 900)
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [], data: %{}, valid?: true>

iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[13:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, is: ~T[12:01:01], delta: 900)
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[13:01:01]}, errors: [meeting_start: {"should be %{is}.", [validation: :time, kind: :is]}], data: %{}, valid?: false>

# Using :before to ensure time is before given time
iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, before: ~T[13:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [], data: %{}, valid?: true>

iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, before: ~T[11:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [meeting_start: {"should be before %{before}.", [validation: :time, kind: :before]}], data: %{}, valid?: false>

# Using :after to ensure time is after given time
iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, after: ~T[11:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [], data: %{}, valid?: true>

iex> types = %{meeting_start: :time}
iex> params = %{meeting_start: ~T[12:01:01]}
iex> Ecto.Changeset.cast({%{}, types}, params, Map.keys(types))
...> |> validate_time(:meeting_start, after: ~T[13:01:01])
#Ecto.Changeset<action: nil, changes: %{meeting_start: ~T[12:01:01]}, errors: [meeting_start: {"should be after %{after}.", [validation: :time, kind: :after]}], data: %{}, valid?: false>