The main purpose of the context package is to define the Context type and support cancellation. Yes, you heard that right; there are times when, for some reason, you want to abandon what you are doing. However, it would be very helpful to be able to include some extra information about your cancellation decisions. The context package allows you to do exactly that.
If you take a look at the source code of the context package, you will realize that its implementation is pretty simple – even the implementation of the Context type is pretty simple, yet the context package is very important.
The context package existed for a while as an external Go package; it first appeared as a standard Go package in Go version 1.7. So, if you have an older Go version, you will not be able to follow this section without first downloading the context package or installing...