chore(exandra): init repo for exandra

Initializing `Repo` module to use `exandra` as adapter for appengine_api

Signed-off-by: Eddy Babetto <eddy.babetto@secomind.com>

Author: eddbbt

apps/astarte_appengine_api/config/config.exs

@@ -8,6 +8,10 @@ import Config
 # General application configuration
 config :astarte_appengine_api, namespace: Astarte.AppEngine.API
 
+config :astarte_appengine_api, ecto_repos: [Astarte.AppEngine.API.Repo]
+
+config :astarte_appengine_api, Astarte.AppEngine.API.Repo
+
 # Configures the endpoint
 config :astarte_appengine_api, Astarte.AppEngine.APIWeb.Endpoint,
   url: [host: "localhost"],

apps/astarte_appengine_api/lib/astarte_appengine_api/application.ex

@@ -55,7 +55,8 @@ defmodule Astarte.AppEngine.API.Application do
       Astarte.AppEngine.API.Rooms.AMQPClient,
       Astarte.AppEngine.APIWeb.Endpoint,
       {Xandra.Cluster, ae_xandra_opts},
-      {Astarte.DataAccess, data_access_opts}
+      {Astarte.DataAccess, data_access_opts},
+      {Astarte.AppEngine.API.Repo, xandra_options}
     ]
 
     # See https://hexdocs.pm/elixir/Supervisor.html

apps/astarte_appengine_api/lib/astarte_appengine_api/repo.ex

@@ -0,0 +1,90 @@
+#
+# This file is part of Astarte.
+#
+# Copyright 2025 SECO Mind Srl
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+# TODO: Copied from astarte_data_access PR #71, see: https://github.com/astarte-platform/astarte_data_access/pull/71
+# use `astarte_data_access` when it will be merged
+defmodule Astarte.AppEngine.API.Repo do
+  @moduledoc false
+  use Ecto.Repo, otp_app: :astarte_appengine_api, adapter: Exandra
+  alias Astarte.DataAccess.Config
+  require Ecto.Query
+
+  @impl Ecto.Repo
+  def init(_context, config) do
+    config =
+      Config.xandra_options!()
+      |> Keyword.merge(config)
+
+    {:ok, config}
+  end
+
+  def fetch(queryable, id, opts \\ []) do
+    queryable
+    |> query_for_get(id)
+    |> fetch_one(opts)
+  end
+
+  def fetch_by(queryable, clauses, opts \\ []) do
+    queryable
+    |> Ecto.Query.where([], ^Enum.to_list(clauses))
+    |> fetch_one(opts)
+  end
+
+  def fetch_one(queryable, opts \\ []) do
+    {error, opts} = Keyword.pop_first(opts, :error, :not_found)
+
+    case all(queryable, opts) do
+      [item] -> {:ok, item}
+      [] -> {:error, error}
+      other -> raise Ecto.MultipleResultsError, queryable: queryable, count: length(other)
+    end
+  end
+
+  # Copyright: elixir-ecto/ecto
+  defp query_for_get(_queryable, nil) do
+    raise ArgumentError, "cannot perform Ecto.Repo.get/2 because the given value is nil"
+  end
+
+  # Copyright: elixir-ecto/ecto
+  defp query_for_get(queryable, id) do
+    query = Ecto.Queryable.to_query(queryable)
+    schema = assert_schema!(query)
+
+    case schema.__schema__(:primary_key) do
+      [pk] ->
+        Ecto.Query.from(x in query, where: field(x, ^pk) == ^id)
+
+      pks ->
+        raise ArgumentError,
+              "Ecto.Repo.get/2 requires the schema #{inspect(schema)} " <>
+                "to have exactly one primary key, got: #{inspect(pks)}"
+    end
+  end
+
+  # Copyright: elixir-ecto/ecto
+  defp assert_schema!(%{from: %{source: {_source, schema}}}) when schema != nil, do: schema
+
+  # Copyright: elixir-ecto/ecto
+  defp assert_schema!(query) do
+    raise Ecto.QueryError,
+      query: query,
+      message: "expected a from expression with a schema"
+  end
+end

apps/astarte_appengine_api/lib/astarte_appengine_api_web/gettext.ex

@@ -37,5 +37,5 @@ defmodule Astarte.AppEngine.APIWeb.Gettext do
 
   See the [Gettext Docs](https://hexdocs.pm/gettext) for detailed usage.
   """
-  use Gettext, otp_app: :astarte_appengine_api
+  use Gettext.Backend, otp_app: :astarte_appengine_api
 end

apps/astarte_appengine_api/mix.exs

@@ -95,6 +95,10 @@ defmodule Astarte.AppEngine.API.Mixfile do
       {:ex_json_schema, "~> 0.7"},
       {:phoenix_swagger, "~> 0.8"},
       {:xandra, "~> 0.13"},
+      {:exandra, "~> 0.12"},
+      {:typed_ecto_schema, "~> 0.4"},
+      # Fix: could not compile dependency due to an old snappy version (1.2.8). Delete when removing xandra
+      {:snappyer, "~> 1.2.10", override: true},
       {:pretty_log, "~> 0.1"},
       {:plug_logger_with_meta, "~> 0.1"},
       {:telemetry, "~> 0.4"},
@@ -111,7 +115,7 @@ defmodule Astarte.AppEngine.API.Mixfile do
       # Test section
       {:excoveralls, "~> 0.15", only: :test},
       {:mox, "~> 0.5", only: :test},
-      {:stream_data, "~> 0.5", only: :test}
+      {:stream_data, "~> 0.5", only: [:test, :dev]}
     ]
   end
 end