wake-up call

noun
1
a phone call that you arrange to be made to you at a particular time, for example in a hotel, in order to wake you up
تماس بیدارباش, زنگ بیداری, تلفن بیداری
2
an event that makes people realize that there is a problem that they need to do something about
زنگ خطر, تلنگر
These riots should be a wake-up call for the government.