Monitor every method call in ruby

Question

Is there a way to wrap all methods defined in my own namespace with a around/before/after filter such that I can log call occurrences and unused methods?

This pattern is usually called "aspect-oriented programming"; searching for Ruby and that should give you a number of different gems you can use; for example, Aspector or Aquarium should be able to do what you want. — Amadan, Feb 03 '17 at 00:17
Possible duplicate of [Executing code for every method call in a Ruby module](http://stackoverflow.com/questions/5513558/executing-code-for-every-method-call-in-a-ruby-module) — Grisha Levit, Feb 03 '17 at 06:05

score 1 · Answer 1 · answered Feb 03 '17 at 01:41

There's quite a bit of work to do to do what you want. Fortunately, you're not the only person that wants it, and it's been done before (as I said in comments, under "aspect-oriented programming".

Here's an example using the Aspector gem:

#!/usr/bin/env ruby

require 'aspector'

watcher = Aspector do
  around(/.*/, except: Object.methods) do |proxy, *args, &block|
    puts "before #{proxy.name} on #{proxy.receiver}"
    proxy.call(*args, &block)
    puts "after #{proxy.name} on #{proxy.receiver}"
  end
end

class Foo
  def self.klass
    puts "class method"
  end
  def inst
    puts "instance method"
  end
end

watcher.apply(Foo)
watcher.apply(Foo, class_methods: true)
# => before singleton_method_added on Foo
#    after singleton_method_added on Foo

Foo.klass
# => before klass on Foo
#    class method
#    after klass on Foo

Foo.new.inst
# => before inst on #<Foo:0x007f9b648c83c0>
#    instance method
#    after inst on #<Foo:0x007f9b648c83c0>

Monitor every method call in ruby

1 Answers1