GoToSocial/internal/concurrency/workers.go

125 lines
3.4 KiB
Go

/*
GoToSocial
Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package concurrency
import (
"context"
"errors"
"fmt"
"path"
"reflect"
"runtime"
"codeberg.org/gruf/go-runners"
"github.com/superseriousbusiness/gotosocial/internal/log"
)
// WorkerPool represents a proccessor for MsgType objects, using a worker pool to allocate resources.
type WorkerPool[MsgType any] struct {
workers runners.WorkerPool
process func(context.Context, MsgType) error
nw, nq int
prefix string // contains type prefix for logging
}
// New returns a new WorkerPool[MsgType] with given number of workers and queue ratio,
// where the queue ratio is multiplied by no. workers to get queue size. If args < 1
// then suitable defaults are determined from the runtime's GOMAXPROCS variable.
func NewWorkerPool[MsgType any](workers int, queueRatio int) *WorkerPool[MsgType] {
var zero MsgType
if workers < 1 {
// ensure sensible workers
workers = runtime.GOMAXPROCS(0) * 4
}
if queueRatio < 1 {
// ensure sensible ratio
queueRatio = 100
}
// Calculate the short type string for the msg type
msgType := reflect.TypeOf(zero).String()
_, msgType = path.Split(msgType)
w := &WorkerPool[MsgType]{
process: nil,
nw: workers,
nq: workers * queueRatio,
prefix: fmt.Sprintf("worker.Worker[%s]", msgType),
}
// Log new worker creation with type prefix
log.Infof("%s created with workers=%d queue=%d",
w.prefix,
workers,
workers*queueRatio,
)
return w
}
// Start will attempt to start the underlying worker pool, or return error.
func (w *WorkerPool[MsgType]) Start() error {
log.Infof("%s starting", w.prefix)
// Check processor was set
if w.process == nil {
return errors.New("nil Worker.process function")
}
// Attempt to start pool
if !w.workers.Start(w.nw, w.nq) {
return errors.New("failed to start Worker pool")
}
return nil
}
// Stop will attempt to stop the underlying worker pool, or return error.
func (w *WorkerPool[MsgType]) Stop() error {
log.Infof("%s stopping", w.prefix)
// Attempt to stop pool
if !w.workers.Stop() {
return errors.New("failed to stop Worker pool")
}
return nil
}
// SetProcessor will set the Worker's processor function, which is called for each queued message.
func (w *WorkerPool[MsgType]) SetProcessor(fn func(context.Context, MsgType) error) {
if w.process != nil {
log.Fatalf("%s Worker.process is already set", w.prefix)
}
w.process = fn
}
// Queue will queue provided message to be processed with there's a free worker.
func (w *WorkerPool[MsgType]) Queue(msg MsgType) {
log.Tracef("%s queueing message (queue=%d): %+v",
w.prefix, w.workers.Queue(), msg,
)
w.workers.Enqueue(func(ctx context.Context) {
if err := w.process(ctx, msg); err != nil {
log.Errorf("%s %v", w.prefix, err)
}
})
}