improvement: custom-extension implementation (#162)

* improvement: custom-extension implementation

* improvement: allow adding custom-extension by module's reference and fixes formatting

* ci: fixes formatter

lib/custom_extension.ex

@@ -0,0 +1,20 @@
+defmodule AshPostgres.CustomExtension do
+  @moduledoc """
+  A custom extension implementation.
+  """
+
+  @callback install(version :: integer) :: String.t()
+
+  @callback uninstall(version :: integer) :: String.t()
+
+  defmacro __using__(name: name, latest_version: latest_version) do
+    quote do
+      @behaviour AshPostgres.CustomExtension
+
+      @extension_name unquote(name)
+      @extension_latest_version unquote(latest_version)
+
+      def extension, do: {@extension_name, @extension_latest_version, &install/1, &uninstall/1}
+    end
+  end
+end

lib/expr.ex

@@ -1106,8 +1106,7 @@ defmodule AshPostgres.Expr do
         Map.get(first_relationship, :manual) ->
           {module, opts} = first_relationship.manual
 
-          [pkey_attr | _] =
-            Ash.Resource.Info.primary_key(first_relationship.destination)
+          [pkey_attr | _] = Ash.Resource.Info.primary_key(first_relationship.destination)
 
           pkey_attr = Ash.Resource.Info.attribute(first_relationship.destination, pkey_attr)
 

lib/join.ex

@@ -264,16 +264,15 @@ defmodule AshPostgres.Join do
           )
       end
 
-    parent_bindings =
-      %{
-        base_bindings
-        | resource: relationship.source,
-          calculations: %{},
-          parent_resources: [],
-          aggregate_defs: %{},
-          context: relationship.context,
-          current: parent_binding + 1
-      }
+    parent_bindings = %{
+      base_bindings
+      | resource: relationship.source,
+        calculations: %{},
+        parent_resources: [],
+        aggregate_defs: %{},
+        context: relationship.context,
+        current: parent_binding + 1
+    }
 
     parent_bindings =
       if bindings do

lib/migration_generator/migration_generator.ex

@@ -180,10 +180,25 @@ defmodule AshPostgres.MigrationGenerator do
             {other, other.installed}
         end
 
-      to_install = List.wrap(repo.installed_extensions()) -- List.wrap(installed_extensions)
+      requesteds =
+        repo.installed_extensions()
+        |> Enum.map(fn
+          extension_module when is_atom(extension_module) ->
+            {ext_name, version, _up_fn, _down_fn} = extension = extension_module.extension()
+
+            {"#{ext_name}_v#{version}", extension}
+
+          extension_name ->
+            {extension_name, extension_name}
+        end)
 
       to_install =
-        if "ash-functions" in repo.installed_extensions() &&
+        requesteds
+        |> Enum.filter(fn {name, _extension} -> !Enum.member?(installed_extensions, name) end)
+        |> Enum.map(fn {_name, extension} -> extension end)
+
+      to_install =
+        if "ash-functions" in requesteds &&
              extensions_snapshot[:ash_functions_version] !=
                @latest_ash_functions_version do
           Enum.uniq(["ash-functions" | to_install])
@@ -197,6 +212,10 @@ defmodule AshPostgres.MigrationGenerator do
       else
         {module, migration_name} =
           case to_install do
+            [{ext_name, version, _up_fn, _down_fn}] ->
+              {"install_#{ext_name}_v#{version}",
+               "#{timestamp(true)}_install_#{ext_name}_v#{version}_extension"}
+
             [single] ->
               {"install_#{single}", "#{timestamp(true)}_install_#{single}_extension"}
 
@@ -222,6 +241,9 @@ defmodule AshPostgres.MigrationGenerator do
             "ash-functions" ->
               install_ash_functions(extensions_snapshot[:ash_functions_version])
 
+            {_ext_name, version, up_fn, _down_fn} when is_function(up_fn, 1) ->
+              up_fn.(version)
+
             extension ->
               "execute(\"CREATE EXTENSION IF NOT EXISTS \\\"#{extension}\\\"\")"
           end)
@@ -231,6 +253,9 @@ defmodule AshPostgres.MigrationGenerator do
             "ash-functions" ->
               "execute(\"DROP FUNCTION IF EXISTS ash_elixir_and(BOOLEAN, ANYCOMPATIBLE), ash_elixir_and(ANYCOMPATIBLE, ANYCOMPATIBLE), ash_elixir_or(ANYCOMPATIBLE, ANYCOMPATIBLE), ash_elixir_or(BOOLEAN, ANYCOMPATIBLE)\")"
 
+            {_ext_name, version, _up_fn, down_fn} when is_function(down_fn, 1) ->
+              down_fn.(version)
+
             extension ->
               "# execute(\"DROP EXTENSION IF EXISTS \\\"#{extension}\\\"\")"
           end)
@@ -257,12 +282,14 @@ defmodule AshPostgres.MigrationGenerator do
         end
         """
 
+        installed = Enum.map(requesteds, fn {name, _extension} -> name end)
+
         snapshot_contents =
           Jason.encode!(
             %{
-              installed: repo.installed_extensions()
+              installed: installed
             }
-            |> set_ash_functions(repo.installed_extensions()),
+            |> set_ash_functions(installed),
             pretty: true
           )
 

priv/resource_snapshots/extensions.json

@@ -4,6 +4,7 @@
     "ash-functions",
     "uuid-ossp",
     "pg_trgm",
-    "citext"
+    "citext",
+    "demo-functions_v1"
   ]
 }

priv/test_repo/migrations/20230804223759_install_demo-functions_v0_extension.exs

@@ -0,0 +1,26 @@
+defmodule AshPostgres.TestRepo.Migrations.InstallDemoFunctionsV0 do
+  @moduledoc """
+  Installs any extensions that are mentioned in the repo's `installed_extensions/0` callback
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    execute("""
+    CREATE OR REPLACE FUNCTION ash_demo_functions()
+    RETURNS boolean AS $$ SELECT TRUE $$
+    LANGUAGE SQL
+    IMMUTABLE;
+    """)
+  end
+
+  def down do
+    # Uncomment this if you actually want to uninstall the extensions
+    # when this migration is rolled back:
+    execute("""
+    DROP FUNCTION IF EXISTS ash_demo_functions()
+    """)
+  end
+end

priv/test_repo/migrations/20230804223818_install_demo-functions_v1_extension.exs

@@ -0,0 +1,26 @@
+defmodule AshPostgres.TestRepo.Migrations.InstallDemoFunctionsV1 do
+  @moduledoc """
+  Installs any extensions that are mentioned in the repo's `installed_extensions/0` callback
+
+  This file was autogenerated with `mix ash_postgres.generate_migrations`
+  """
+
+  use Ecto.Migration
+
+  def up do
+    execute("""
+    CREATE OR REPLACE FUNCTION ash_demo_functions()
+    RETURNS boolean AS $$ SELECT FALSE $$
+    LANGUAGE SQL
+    IMMUTABLE;
+    """)
+  end
+
+  def down do
+    # Uncomment this if you actually want to uninstall the extensions
+    # when this migration is rolled back:
+    execute("""
+    DROP FUNCTION IF EXISTS ash_demo_functions()
+    """)
+  end
+end

test/support/test_custom_extension.ex

@@ -0,0 +1,38 @@
+defmodule AshPostgres.TestCustomExtension do
+  @moduledoc false
+
+  use AshPostgres.CustomExtension, name: "demo-functions", latest_version: 1
+
+  @impl true
+  def install(0) do
+    """
+    execute(\"\"\"
+    CREATE OR REPLACE FUNCTION ash_demo_functions()
+    RETURNS boolean AS $$ SELECT TRUE $$
+    LANGUAGE SQL
+    IMMUTABLE;
+    \"\"\")
+    """
+  end
+
+  @impl true
+  def install(1) do
+    """
+    execute(\"\"\"
+    CREATE OR REPLACE FUNCTION ash_demo_functions()
+    RETURNS boolean AS $$ SELECT FALSE $$
+    LANGUAGE SQL
+    IMMUTABLE;
+    \"\"\")
+    """
+  end
+
+  @impl true
+  def uninstall(_version) do
+    """
+    execute(\"\"\"
+    DROP FUNCTION IF EXISTS ash_demo_functions()
+    \"\"\")
+    """
+  end
+end

test/support/test_no_sandbox_repo.ex

@@ -8,7 +8,7 @@ defmodule AshPostgres.TestNoSandboxRepo do
   end
 
   def installed_extensions do
-    ["ash-functions", "uuid-ossp", "pg_trgm", "citext"] --
+    ["ash-functions", "uuid-ossp", "pg_trgm", "citext", AshPostgres.TestCustomExtension] --
       Application.get_env(:ash_postgres, :no_extensions, [])
   end
 

test/support/test_repo.ex

@@ -8,7 +8,7 @@ defmodule AshPostgres.TestRepo do
   end
 
   def installed_extensions do
-    ["ash-functions", "uuid-ossp", "pg_trgm", "citext"] --
+    ["ash-functions", "uuid-ossp", "pg_trgm", "citext", AshPostgres.TestCustomExtension] --
       Application.get_env(:ash_postgres, :no_extensions, [])
   end
 

test_snapshot_path/extensions.json

@@ -1,9 +1,10 @@
 {
+  "ash_functions_version": 1,
   "installed": [
     "ash-functions",
     "uuid-ossp",
     "pg_trgm",
-    "citext"
-  ],
-  "ash_functions_version": 1
+    "citext",
+    "demo-functions_v1"
+  ]
 }