Finch: Failed to lookup telemetry handlers

kevinlang · May 3, 2023, 5:12am

Found it. The discrepancy lies in the fact that Mix.install/1 starts the application for each dependency by default.

elixir-lang/elixir/blob/44e6f57cde5abe1ae0ce81d869748e94e47dd2b0/lib/mix/lib/mix.ex#L881


      
          
          
      Mix.Task.rerun("compile")
          
          
      if config_path do
                  Mix.Task.rerun("app.config")
                end
              end)
          
          
    for %{app: app, opts: opts} <- Mix.Dep.cached(),
                  Keyword.get(opts, :runtime, true) and Keyword.get(opts, :app, true) do
                Application.ensure_all_started(app)
              end
          
          
    Mix.State.put(:installed, id)
              :ok
            after
              Mix.ProjectStack.pop()
            end
          
          
^id when not force? ->
            :ok

Solution is to just add Application.ensure_started(:telemetry) at the beginning of the Mix task.