Need for context

The context.Context interface

type Context interface {
    Deadline() (deadline time.Time, ok bool)
    Done() <-chan struct{}
    Err() error
    Value(key any) any
}

Understanding each Method

1. Done

Go's focus on concurrency resulting in need of interrupting spawned goroutines
Done's return value tells if the parent function in the chain has asked to stop the work

2. Deadline

Go was also supposed to work as a language for microservices or systems interacting with external resources.
Whenever we are interacting with external systems, it is better to set a deadline for that interaction

3. Err

Err returns one of two types of values. Either context.Canceled error or context.DeadlineExceeded.
It just differenciates why the context says that work needs to be stopped/cancelled

4. Value

Probably the only field that makes sense of the package name
Extensively used in server side code to store request scoped variables like "authenticated_user","trace_id", "role", etc.