1 files changed, 64 insertions, 0 deletions
diff --git a/lib/cepis/health.ex b/lib/cepis/health.ex
new file mode 100644
index 0000000..9a25c83
--- /dev/null
+++ b/lib/cepis/health.ex
@@ -0,0 +1,64 @@
+defmodule Cepis.Health do
+  @moduledoc """
+  The response of `GET /health`.
+
+  Good for two things: checking that the API answers, and knowing **which
+  version of the database** is live. The DNE database changes every two weeks;
+  `dne` identifies it.
+  """
+
+  defstruct status: "", dne: "", ceps: 0, geo: 0, base_gerada_em: ""
+
+  @type t :: %__MODULE__{
+          status: String.t(),
+          dne: String.t(),
+          ceps: non_neg_integer(),
+          geo: non_neg_integer(),
+          base_gerada_em: String.t()
+        }
+
+  @doc """
+  `true` when the API reports itself healthy.
+  """
+  @spec ok?(t()) :: boolean()
+  def ok?(%__MODULE__{status: status}), do: status == "ok"
+
+  @doc false
+  @spec from_map(map()) :: t()
+  def from_map(data) when is_map(data) do
+    %__MODULE__{
+      status: text(data, "status"),
+      dne: text(data, "dne"),
+      ceps: count(data, "ceps"),
+      geo: count(data, "geo"),
+      base_gerada_em: text(data, "base_gerada_em")
+    }
+  end
+
+  defp text(data, key) do
+    case Map.get(data, key) do
+      value when is_binary(value) -> value
+      value when is_number(value) -> to_string(value)
+      _ -> ""
+    end
+  end
+
+  defp count(data, key) do
+    case Map.get(data, key) do
+      value when is_integer(value) ->
+        value
+
+      value when is_float(value) ->
+        trunc(value)
+
+      value when is_binary(value) ->
+        case Integer.parse(value) do
+          {number, _} -> number
+          :error -> 0
+        end
+
+      _ ->
+        0
+    end
+  end
+end