This example demonstrates the use of shutdown service gracefully.

ExitWaitGroupAdd waitgroup counter adds delta.

ExitWaitGroupDone waitgroup down.

NewContext create new context.

Shutdown shutdown gracefully.

WaitAndShutdown shutdown gracefully.

WaitTerminationSignal 等待退出信号.

ContextCancel cancel func value name in context.

ContextExitWaitGroup waitgroup object name in context.

ErrCancelValueTypeError cancel value in context type error.

ErrExitWaitGroupValueTypeError exitWaitGroup value in context type error.

ErrNoCancel no cancel value error.

ErrNoExitWaitGroup no exitWaitGroup value in context.

ErrShutdownTimeout shutdown timeout.

TerminationSignals 退出信号量.

CloseFunc close function.

ContextKey context key type.