Query Logging: Appsignal.Ecto.log/1 errors when using the preferred Ecto.Repo loggers format

[wheels]

From the Ecto docs:

:loggers - a list of {mod, fun, args} tuples...

https://hexdocs.pm/ecto/Ecto.Repo.html

In Ecto 2.0.2, when I add Appsignal to Repo loggers using the preferred format

loggers: [{Appsignal.Ecto, :log, []}]

it throws an error here:

https://github.com/appsignal/appsignal-elixir/blob/master/lib/appsignal/ecto.ex#L29

** (exit) an exception was raised:
    ** (UndefinedFunctionError) function nil.queue_time/0 is undefined or private
        nil.queue_time()
        (appsignal) Appsignal.Ecto.log/1

[arjan]

Sorry, I can't seem to reproduce this. Are you using the latest version? It seems the LogEntry that's passed in is nil..

I also don't see how this variant could cause the error, they look pretty similar. Are you doing something special? e.g. when there is another logger that does not return the entry value back, the next logger function could crash.

[wheels]

It only happens in prod for me. I'm passing in other loggers as well so it looks like this:

loggers: [{Ecto.LogEntry, :log, []}, {MyApp.Repo.Metrics, :record_metric, []}, {Appsignal.Ecto, :log, []]

[arjan]

You should check whether your record_metric function returns the log entry.

[wheels]

Ah, nice catch. Didn't realize each one affected subsequent calls.

[arjan]

NP! I also just realised this by looking at Ecto's source.