API read failures sometimes return 200 with empty body

[adstage-david]

In my example based on the cookbook, clicking the new button causes the failure state I've seen in our production app:

untangled-web/untangled-cookbook#5

Essentially if some random function throws an exception during a read error, it's not properly caught and handled.

[awkay]

@egracer, was this due to the Om parser swallowing them?

[egracer]

@awkay I don't believe so, because the default server read throws an error that is successfully propagated to the client.