partition by org_id and add auth

lib/customer_service_web/plugs/authorize_roles.ex

@@ -0,0 +1,81 @@
+defmodule CustomerServiceWeb.Plugs.AuthorizeRoles do
+  @moduledoc """
+  Authorize request based on Zitadel role permissions.
+
+  After token introspection, checks if the user holds any of the
+  `required_permissions` roles for the organization identified by
+  `X-Organization-Id` header.
+
+  The Zitadel roles claim structure is:
+  %{"urn:zitadel:iam:org:project:<project_id>:roles": {
+    "<role>": {
+      "<org_id>": "<org_domain>"
+    },
+    "<role>": {
+      "<org_id>": "<org_domain>"
+    }
+  }}
+  """
+
+  @behaviour Plug
+
+  import Plug.Conn
+
+  @impl Plug
+  def init(opts),
+    do:
+      opts
+      |> Keyword.validate!([
+        :roles_claim
+      ])
+
+  @impl Plug
+  def call(conn, opts) do
+    if authorized?(
+         conn,
+         Keyword.get(opts, :roles_claim),
+         Keyword.get(opts, :required_permissions)
+       ) do
+      conn
+    else
+      conn
+      |> put_resp_content_type("application/json")
+      |> halt()
+      |> send_resp(
+        :forbidden,
+        Jason.encode_to_iodata!(%{error: "Forbidden", reason: "Missing required role"})
+      )
+    end
+  end
+
+  defp authorized?(conn, roles_claim, required_permissions) do
+    org_id = conn.private[CustomerServiceWeb.Plugs.ExtractOrganizationId]
+
+    with true <- org_id_given?(org_id),
+         roles_map <- get_roles_map(conn, roles_claim),
+         true <- has_any_role?(roles_map, org_id, required_permissions) do
+      true
+    else
+      _ -> false
+    end
+  end
+
+  defp org_id_given?(org_id), do: not is_nil(org_id)
+
+  defp get_roles_map(conn, roles_claim) do
+    case conn.private[Oidcc.Plug.IntrospectToken] do
+      %Oidcc.TokenIntrospection{extra: extra} ->
+        Map.get(extra, roles_claim, %{})
+
+      _ ->
+        %{}
+    end
+  end
+
+  defp has_any_role?(roles_map, org_id, required_permissions) do
+    Enum.any?(required_permissions, fn role ->
+      role_orgs = Map.get(roles_map, role, %{})
+      Map.has_key?(role_orgs, org_id)
+    end)
+  end
+end