View Source Flexto (bonfire v0.3.0-classic-beta.4)

Configuration-driven Ecto Schemata.

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Adds additional associations dynamically from app config.

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Adds additional associations dynamically from app config.

Reads config for the given OTP application, under the name of the current module. Each key maps to an Ecto.Schema function:

  • belongs_to
  • field
  • has_many
  • has_one
  • many_to_many

Each of these keys should map to a keyword list where the key is the name of the field or association and the value is one of:

  • A type
  • A tuple of type and options (keyword list)

Example Schema:

defmodule My.Schema do
  use Ecto.Schema
  import Flexto, only: [flex_schema: 1]

  schema "my_table" do
    field :name, :string # just normal schema things
    flex_schema(:my_app) # boom! give me the stuff

Example configuration:

config :my_app, My.Schema,
  belongs_to: [
    foo: Foo,                   # belongs_to :foo, Foo
    bar: {Bar, type: :integer}, # belongs_to :bar, Bar, type: :integer
  field: [
    foo: :string,                # field :foo, :string
    bar: {:integer, default: 4}, # field :foo, :integer, default: 4
  has_one: [
    foo: Foo,                             # has_one :foo, Foo
    bar: {Bar, foreign_key: :the_bar_id}, # has_one :bar, Bar, foreign_key: :the_bar_id
  has_many: [
    foo: Foo,                             # has_many :foo, Foo
    bar: {Bar, foreign_key: :the_bar_id}, # has_many :bar, Bar, foreign_key: :the_bar_id
  many_to_many: [
    foo: Foo,                         # many_to_many :foo, Foo
    bar: {Bar, join_through: FooBar}, # many_to_many :bar, Bar, :join_through: FooBar

This one won't work very well because we define foo and bar 5 times each, but I think you get the point.

Reading of configuration is done during compile time. The relations will be baked in during compilation, thus:

  • Do not expect this to work in release config.
  • You will need to rebuild all dependencies which use this macro when you change their configuration.