You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
gitea-fork-majority-judgment/modules/graceful/context.go

91 lines
2.5 KiB

// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package graceful
import (
"context"
"fmt"
"time"
)
// Errors for context.Err()
var (
ErrShutdown = fmt.Errorf("Graceful Manager called Shutdown")
ErrHammer = fmt.Errorf("Graceful Manager called Hammer")
ErrTerminate = fmt.Errorf("Graceful Manager called Terminate")
)
// ChannelContext is a context that wraps a channel and error as a context
type ChannelContext struct {
done <-chan struct{}
err error
}
// NewChannelContext creates a ChannelContext from a channel and error
func NewChannelContext(done <-chan struct{}, err error) *ChannelContext {
return &ChannelContext{
done: done,
err: err,
}
}
// Deadline returns the time when work done on behalf of this context
// should be canceled. There is no Deadline for a ChannelContext
func (ctx *ChannelContext) Deadline() (deadline time.Time, ok bool) {
return
}
// Done returns the channel provided at the creation of this context.
// When closed, work done on behalf of this context should be canceled.
func (ctx *ChannelContext) Done() <-chan struct{} {
return ctx.done
}
// Err returns nil, if Done is not closed. If Done is closed,
// Err returns the error provided at the creation of this context
func (ctx *ChannelContext) Err() error {
select {
case <-ctx.done:
return ctx.err
default:
return nil
}
}
// Value returns nil for all calls as no values are or can be associated with this context
func (ctx *ChannelContext) Value(key interface{}) interface{} {
return nil
}
// ShutdownContext returns a context.Context that is Done at shutdown
// Callers using this context should ensure that they are registered as a running server
// in order that they are waited for.
func (g *Manager) ShutdownContext() context.Context {
return &ChannelContext{
done: g.IsShutdown(),
err: ErrShutdown,
}
}
// HammerContext returns a context.Context that is Done at hammer
// Callers using this context should ensure that they are registered as a running server
// in order that they are waited for.
func (g *Manager) HammerContext() context.Context {
return &ChannelContext{
done: g.IsHammer(),
err: ErrHammer,
}
}
// TerminateContext returns a context.Context that is Done at terminate
// Callers using this context should ensure that they are registered as a terminating server
// in order that they are waited for.
func (g *Manager) TerminateContext() context.Context {
return &ChannelContext{
done: g.IsTerminate(),
err: ErrTerminate,
}
}