write config provider

1 files changed, 61 insertions, 0 deletions

diff --git a/apps/thulani_bot/lib/thulani/bot/env_config_provider.ex b/apps/thulani_bot/lib/thulani/bot/env_config_provider.ex
new file mode 100644
index 0000000..c8815e0
--- /dev/null
+++ b/apps/thulani_bot/lib/thulani/bot/env_config_provider.ex
@@ -0,0 +1,61 @@
+defmodule Thulani.Bot.EnvConfigProvider do
+  @behaviour Config.Provider
+
+  @env_vars %{
+    database_url: nil,
+    spreadsheet_id: nil,
+    sheets_api_key: nil,
+    steam_api_key: nil,
+    max_sheet_column: "zz",
+    default_hist: "5",
+    max_hist: "30"
+  }
+
+  def init(prefix) do
+    "#{String.upcase(prefix)}_"
+  end
+
+  def load(config, prefix) do
+    logger_config =
+      if System.get_env("#{prefix}DEBUG") do
+        %{
+          logger: [level: :debug]
+        }
+      else
+        %{}
+      end
+
+    result =
+      %{
+        nostrum: [
+          token: System.fetch_env!("#{prefix}TOKEN"),
+          shards: System.get_env("#{prefix}DISCORD_SHARDS", "1") |> Integer.parse()
+        ],
+        thulani_bot: thulani_env(prefix)
+      }
+      |> Map.merge(logger_config)
+
+    IO.inspect(Config.Reader.merge(config, result))
+  end
+
+  defp thulani_env(prefix) do
+    @env_vars
+    |> Enum.map(fn {env_var, default} ->
+      canonical_env_var =
+        env_var
+        |> to_string
+        |> String.upcase()
+        |> (fn x -> prefix <> x end).()
+
+      value =
+        canonical_env_var
+        |> System.get_env(default)
+
+      if value == nil do
+        raise "required environment variable not found: #{canonical_env_var}"
+      end
+
+      {env_var, value}
+    end)
+  end
+end