View Source EctoDiscriminator.DiscriminatorType (ecto_discriminator v0.2.6)

A custom type used by the EctoDiscriminator.Schema to know which field should be used for its logic.

EctoDiscriminator.DiscriminatorType field holds name of the diverged module. Field name can be anything. User has to mark exactly one field in the base schema with this type. Diverged schemas will inherit this setting. Forgetting to add this field will result in compilation error. Basic setup:

field :type, EctoDiscriminator.DiscriminatorType

You can also use it as a primary key:

@primary_key {:id, EctoDiscriminator.DiscriminatorType, []}

You can configure any options that are supported by Ecto.Schema (except virtual and default from obvious reasons).

field :discriminator, EctoDiscriminator.DiscriminatorType, load_in_query: false

When it comes to the migrations, the underlying type is just :string. That said, it's completely fine to create migration with string field:

add :type, :string

It's possible to be more restrictive and provide an enum inside DB. Keep in mind that module name will be stored in form Elixir.Module.Name.

Link to this section Summary

Functions

Callback implementation for Ecto.Type.cast/1.

Callback implementation for Ecto.Type.dump/1.

Callback implementation for Ecto.Type.embed_as/1.

Callback implementation for Ecto.Type.equal?/2.

Callback implementation for Ecto.Type.load/1.

Callback implementation for Ecto.Type.type/0.

Link to this section Functions

Callback implementation for Ecto.Type.cast/1.

Callback implementation for Ecto.Type.dump/1.

Callback implementation for Ecto.Type.embed_as/1.

Callback implementation for Ecto.Type.equal?/2.

Callback implementation for Ecto.Type.load/1.

Callback implementation for Ecto.Type.type/0.