Relaxing Grafana client error conditions

lib/prom_ex/grafana_client.ex

@@ -12,6 +12,15 @@ defmodule PromEx.GrafanaClient do
 
   alias PromEx.GrafanaClient.Connection
 
+  @status_codes %{
+    200 => :ok,
+    400 => :bad_request,
+    401 => :unauthorized,
+    403 => :forbidden,
+    404 => :not_found,
+    412 => :already_exists
+  }
+
   @typep handler_response ::
            {:ok, result :: map()} | {:error, reason :: atom()} | {:error, reason :: Mint.TransportError.t()}
 
@@ -143,26 +152,19 @@ defmodule PromEx.GrafanaClient do
 
   defp handle_grafana_response(finch_response) do
     case finch_response do
-      {:ok, %Finch.Response{status: 200, body: body}} ->
+      {:ok, %Finch.Response{status: status_code, body: body}} when status_code in [200, 201] ->
         {:ok, Jason.decode!(body)}
 
-      {:ok, %Finch.Response{status: 400}} ->
-        {:error, :bad_request}
-
-      {:ok, %Finch.Response{status: 401}} ->
-        {:error, :unauthorized}
-
-      {:ok, %Finch.Response{status: 404}} ->
-        {:error, :not_found}
-
-      {:ok, %Finch.Response{status: 412}} ->
-        {:error, :already_exists}
+      {:ok, %Finch.Response{status: status_code} = response} ->
+        Logger.warn("Recieved a #{status_code} from Grafana because: #{inspect(response)}")
+        {:error, lookup_status_code(status_code)}
 
       {:error, %Mint.TransportError{} = mint_error_reason} ->
         {:error, Exception.message(mint_error_reason)}
 
-      {:error, _unknown_reason} = error ->
-        error
+      unknown_response ->
+        Logger.warn("Recieved an unhandled response from Grafana because: #{inspect(unknown_response)}")
+        {:error, :unkown}
     end
   end
 
@@ -189,4 +191,8 @@ defmodule PromEx.GrafanaClient do
     |> Map.put(:dashboard, dashboard)
     |> Jason.encode!()
   end
+
+  defp lookup_status_code(status_code) do
+    Map.get(@status_codes, status_code, :unknown)
+  end
 end

test/prom_ex/dashboard_uploader_test.exs

@@ -39,6 +39,46 @@ defmodule PromEx.DashboardUploaderTest do
     {:ok, bypass: bypass}
   end
 
+  test "should handle HTTP errors", %{bypass: bypass} do
+    response_payload = """
+    {
+      "message": "Unauthorized request"
+    }
+    """
+
+    Application.put_env(:prom_ex, DefaultPromExSetUp,
+      grafana: [
+        host: endpoint_url(bypass.port),
+        auth_token: "random_token",
+        folder_name: "Web App Dashboards",
+        annotate_app_lifecycle: false
+      ]
+    )
+
+    folder_uid = DefaultPromExSetUp.__grafana_folder_uid__()
+
+    Bypass.expect_once(bypass, "GET", "/api/folders/#{folder_uid}", fn conn ->
+      Plug.Conn.resp(conn, 401, response_payload)
+    end)
+
+    assert capture_log(fn ->
+             {:ok, pid} =
+               start_supervised(
+                 {
+                   DashboardUploader,
+                   [
+                     name: DefaultPromExSetUp.__dashboard_uploader_name__(),
+                     prom_ex_module: DefaultPromExSetUp,
+                     default_dashboard_opts: []
+                   ]
+                 },
+                 restart: :temporary
+               )
+
+             wait_for_process(pid, 1_000)
+           end) =~ "Recieved a 401 from Grafana because"
+  end
+
   test "should check for existing folders", %{bypass: bypass} do
     response_payload = """
     {