Hi all,
A beginner here. I have the following plug code from an example Auth0 repo:
def call(conn, _default) do
with {:ok, token} when is_binary(token) <- get_token(conn),
{:ok, claims} <- Token.verify_and_validate(token) do
conn
|> assign(:claims, claims)
else
{:error, error} -> handle_error_response(conn, error)
end
end
defp get_token(conn) do
case get_req_header(conn, "authorization") do
["Bearer " <> token] -> {:ok, token}
["bearer " <> token] -> {:ok, token}
[] -> {:error, :missing_token}
["Bearer"] -> {:error, :invalid_token}
_ -> {:error, :invalid_token}
end
end
defp handle_error_response(conn, error) do
IO.inspect(error, label: "error")
conn
|> put_status(401)
|> json(%{error: error})
|> halt()
end
end
Now all works as expected until I use an expired JWT, which gives a more complex error message:
error: [message: "Invalid token", claim: "exp", claim_val: 1675775785]
[info] Sent 500 in 59ms
[error] #PID<0.13753.0> running Phoenix.Endpoint.SyncCodeReloadPlug (connection #PID<0.13752.0>, stream id 1) terminated
Server: localhost:4000 (http)
Request: GET /api/phone-numbers/44790323266
** (exit) an exception was raised:
** (Protocol.UndefinedError) protocol Jason.Encoder not implemented for {:message, "Invalid token"} of type Tuple, Jason.Encoder protocol must always be explicitly implemented. This protocol is implemented for the following type(s): Any, Atom, BitString, Date, DateTime, Decimal, Ecto.Association.NotLoaded, Ecto.Schema.Metadata, Float, Integer, Jason.Fragment, Jason.OrderedObject, List, Map, MixAudit.Advisory, MixAudit.Dependency, MixAudit.Report, MixAudit.Vulnerability, NaiveDateTime, Sentrypeer.SentrypeerEvents.SentrypeerEvent, Time
(jason 1.4.0) lib/jason.ex:213: Jason.encode_to_iodata!/2
(phoenix 1.7.0-rc.2) lib/phoenix/controller.ex:346: Phoenix.Controller.json/2
using a malformed JWT just creates a single atom error like :signature_error
.
What docs do you recommend I read to understand how to pick apart/pattern match/case the error getting passed into handle_error_response so json()
can handle it?
I tried:
if Map.has_key(error, :message) do
conn
|> put_status(401)
|> json(%{error: error["message"]})
|> halt()
else
conn
|> put_status(401)
|> json(%{error: error})
|> halt()
end
but that’s not right and even if I got the if
right, it smells funny.
Thanks for any pointers you can give me.
Gavin.