Lotus.Source.Adapters.Ecto (Lotus v1.0.0)

Adapter wrapping any Ecto.Repo module in the Lotus.Source.Adapter behaviour.

Delegates database-specific operations to dialect modules under Lotus.Source.Adapters.Ecto.Dialects.* based on the repo's underlying Ecto adapter.

Usage

adapter = Lotus.Source.Adapters.Ecto.wrap("main", MyApp.Repo)

Lotus.Source.Adapter.execute_query(adapter, "SELECT 1", [], [])
Lotus.Source.Adapter.list_schemas(adapter)

The state field of the resulting %Adapter{} struct holds the repo module itself, since Ecto repos are statically supervised and don't require explicit connection management.

Extending with custom Ecto-backed adapters

External libraries can create Ecto-backed adapters by writing a dialect module and a one-liner adapter:

defmodule LotusMSSql.Adapter do
  use Lotus.Source.Adapters.Ecto, dialect: LotusMSSql.Dialect
end

The use macro injects default implementations for all Lotus.Source.Adapter callbacks, delegating shared Ecto logic to helper functions in this module and dialect-specific callbacks to the provided :dialect module. All callbacks are defoverridable.

Summary

Functions

builtin_adapters()

Returns the list of built-in per-dialect Ecto adapter modules.

can_handle?(repo)

Whether this adapter can handle the given data source entry.

detect_source_type(repo_module)

Detects the source type from a repo module's underlying Ecto adapter.

wrap(name, repo_module)

Wraps an Ecto.Repo module in an %Adapter{} struct.

Functions

builtin_adapters()

Returns the list of built-in per-dialect Ecto adapter modules.

Used by Lotus.Source.Resolvers.Static to avoid duplicating this list.

can_handle?(repo)

@spec can_handle?(term()) :: boolean()

Whether this adapter can handle the given data source entry.

Returns true for any module that exports __adapter__/0. This is intentionally broad — it acts as a catch-all fallback for Ecto repos that don't match a more specific per-dialect adapter. The resolver checks per-dialect adapters first (via builtin_adapters/0 and source_adapters config), so this only matches repos with unknown Ecto adapters.

detect_source_type(repo_module)

@spec detect_source_type(module()) :: Lotus.Source.Adapter.source_type()

Detects the source type from a repo module's underlying Ecto adapter.

Examples

iex> Lotus.Source.Adapters.Ecto.detect_source_type(MyApp.Repo)
:postgres

wrap(name, repo_module)

@spec wrap(String.t(), module()) :: Lotus.Source.Adapter.t()

Wraps an Ecto.Repo module in an %Adapter{} struct.

The resulting adapter delegates all callbacks to the appropriate source implementation based on the repo's underlying Ecto adapter.

Parameters

name — a human-readable identifier (e.g. "main", "warehouse")
repo_module — the Ecto.Repo module (e.g. MyApp.Repo)

Examples

iex> adapter = Lotus.Source.Adapters.Ecto.wrap("main", MyApp.Repo)
%Lotus.Source.Adapter{name: "main", module: Lotus.Source.Adapters.Ecto, ...}