Cannot set attribute @doc inside function/macro compile error

Questions / Help
1

Hello,

First time posting - I’m following along with Pluralsight’s Elixir intro tutorial that’s having me build some type of cron scheduler.

In the tutorial they’re using quantom to schedule cron jobs but I decided to use Cronex. I followed the Cronex docs but I can’t get the file to compile.

scheduler.ex

defmodule PluralsightTweet.Scheduler do
	use Cronex.Scheduler

	def schedule_file(file) do 
		every :minute do
			PluralsightTweet.FileReader.get_string_to_tweet(file) 
	  	end
	end 
end

error:
== Compilation error in file lib/pluralsight_tweet/scheduler.ex ==
** (ArgumentError) cannot set attribute @doc inside function/macro

Could anyone point out what I’m doing wrong?

Thanks!

2

Hi, welcome to the forum,

You are not using the right syntax… see the example in the documentation.

defmodule MyApp.Scheduler do
  use Cronex.Scheduler

  every :hour do
    IO.puts "Every hour job"
  end

  every :day, at: "10:00" do
    IO.puts "Every day job at 10:00"
  end
end

As You can see, it is not wrapped inside def block…

I get the same error if I use your syntax.

3

Thanks for the reply, I noticed the difference in syntax as well.

However, what I wanted to do was wrap the every in another function so that I could call it from another module (or from iex like so >> PluralsightTweet.Scheduler.schedule_file("/my/path/to/file.txt") )

In this case the wrapping function would be “schedule_file”. Is something like that possible?

Thanks again!

4

I have not seen any clear way to pass parameters to every, but I guess the block it executes could simply work with parameterized jobs, within a queue, and other modules could push any job to the queue, with customized params.

BTW cron is also working like this… at a given time, it will trigger a script, and there is no way to pass a parameter to it.

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