EffectEcto

Elixir library that provides effects for default ecto operations.

Usage

Defined effects

It provides effects for every callback that exists in Ecto.Repo:

• EffectEcto.all(queryable, opts)
• EffectEcto.delete(schema_or_changeset, opts)
• EffectEcto.get(queryable, id, opts)
• EffectEcto.get_by(queryable, keys, opts)
• EffectEcto.insert(insertable, opts)
• EffectEcto.insert_all(schema_or_source, entries_or_query, opts)
• EffectEcto.insert_or_update(changeset, opts)
• EffectEcto.one(queryable, opts)
• EffectEcto.preload(data, preloads, opts)
• EffectEcto.transaction(effect, opts)
• EffectEcto.update(changeset, opts)
• EffectEcto.update_all(queryable, updates, opts)

The most notable among them is EffectEcto.Transaction that allows us to wrap any effect into a database migration.

iex(1)> alias Effect.Pipe
iex(2)> alias MyApp.Repo
iex(3)> Pipe.new()
...(3)> |> Pipe.then(:insert, fn _ -> EffectEcto.insert(%Data{x: 1}) end)
...(3)> |> Pipe.then(:fail, fn _ -> Effect.fail("oops") end)
...(3)> |> EffectEcto.transaction()
...(3)> |> Effect.execute()
{:error, %{fail: "oops"}} # Rollback will be called and nothing will be inserted.

You also have a way to wrap Ecto.Multi struct:

iex(1)> alias Ecto.Multi
iex(2)> MyApp.Repo
iex(3)> multi = Multi.insert(Multi.new(), :insert, %Data{x: 1})
iex(4)> multi
...(4)> |> EffectEcto.multi()
...(4)> |> Effect.execute()
{:ok, %{insert: %Data{x: 1}}}

Protocol implementation

When useing EffectEcto, you generate implementation for Effect.Executable with the repo module you are using it.

defmodule MyApp.Repo do
  use Ecto.Repo, # ...
  use EffectEcto
end

# Now this code may be executed:
%Data{x: 1} |> EffectEcto.insert() |> Effect.execute()

Installation

def deps do
  [
    {:effect_ecto, git: "https://github.com/yunmikun2/effect_ecto", tag: "v0.2.0"}
  ]
end