neiam /apollos_crib

It's Apollo's Crib

GBFS: a feed that is not JSON is logged and skipped, not a KeyError

b0284cc · Gabe Morell · 2026-11-04 21:40

8 files +43 -7

Message

{commit_body(@commit)}

modified apps/room_gbfs/lib/room_gbfs/gbfs_worker.ex

+18 −7

@@ -123,13 +123,9 @@ defmodule RoomGbfs.Worker do

123	123	# the body is an empty redirect page.
124	124	case HTTPoison.get(url, [], follow_redirect: true) do
125	125	{:ok, result} ->
126		− case result.body
127		− \|> Jason.decode(keys: :atoms) do
128		− {:ok, json} ->
129		− write_feed(type, json, id, dt, lang)
130		−
131		− {:error, info} ->
132		− Logger.info(info.reason)
	126	+ case decode_feed(result.body, id, url) do
	127	+ {:ok, json} -> write_feed(type, json, id, dt, lang)
	128	+ :error -> :error
133	129	end
134	130
135	131	{:error, info} ->

@@ -137,6 +133,21 @@ defmodule RoomGbfs.Worker do

137	133	end
138	134	end
139	135
	136	+ # A %Jason.DecodeError{} has no :reason -- reading one raised a KeyError of
	137	+ # its own, so a feed that came back as an HTML error page took the worker
	138	+ # down instead of being skipped until the next pass.
	139	+ @doc false
	140	+ def decode_feed(body, id, url) do
	141	+ case Jason.decode(body, keys: :atoms) do
	142	+ {:ok, json} ->
	143	+ {:ok, json}
	144	+
	145	+ {:error, error} ->
	146	+ Logger.error("GBFS::#{id} #{url} returned non-JSON: #{Exception.message(error)}")
	147	+ :error
	148	+ end
	149	+ end
	150	+
140	151	defp write_feed(:sys_info, json, id, _dt, lang) do
141	152	Repo.insert(
142	153	RoomSanctum.Storage.change_sys_info(

added apps/room_gbfs/test/room_gbfs/worker_decode_test.exs

+25 −0

@@ -0,0 +1,25 @@

	1	+defmodule RoomGbfs.WorkerDecodeTest do
	2	+ use ExUnit.Case, async: true
	3	+
	4	+ import ExUnit.CaptureLog
	5	+
	6	+ alias RoomGbfs.Worker
	7	+
	8	+ test "a feed body that is JSON decodes with atom keys" do
	9	+ assert {:ok, %{data: %{stations: []}}} =
	10	+ Worker.decode_feed(~s({"data": {"stations": []}}), 7, "http://x/si.json")
	11	+ end
	12	+
	13	+ # %Jason.DecodeError{} has no :reason, so the error branch used to raise a
	14	+ # KeyError of its own and take the worker down with it -- over exactly the
	15	+ # body (an HTML error page, a truncated download) it was there to survive.
	16	+ test "a body that is not JSON is logged and skipped rather than raising" do
	17	+ log =
	18	+ capture_log(fn ->
	19	+ assert :error = Worker.decode_feed("<html>gateway timeout</html>", 7, "http://x/ss.json")
	20	+ end)
	21	+
	22	+ assert log =~ "GBFS::7"
	23	+ assert log =~ "http://x/ss.json"
	24	+ end
	25	+end

Parents: 1af73d2