GoToSocial/internal/workers/worker_fn.go

143 lines
3.5 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// 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 workers
import (
"context"
"codeberg.org/gruf/go-runners"
"github.com/superseriousbusiness/gotosocial/internal/log"
"github.com/superseriousbusiness/gotosocial/internal/queue"
"github.com/superseriousbusiness/gotosocial/internal/util"
)
// FnWorkerPool wraps multiple FnWorker{}s in
// a singular struct for easy multi start / stop.
type FnWorkerPool struct {
// Queue is embedded queue.SimpleQueue{}
// passed to each of the pool Worker{}s.
Queue queue.SimpleQueue[func(context.Context)]
// internal fields.
workers []*FnWorker
}
// Start will attempt to start 'n' FnWorker{}s.
func (p *FnWorkerPool) Start(n int) {
// Check whether workers are
// set (is already running).
ok := (len(p.workers) > 0)
if ok {
return
}
// Allocate new workers slice.
p.workers = make([]*FnWorker, n)
for i := range p.workers {
// Allocate new FnWorker{}.
p.workers[i] = new(FnWorker)
p.workers[i].Queue = &p.Queue
// Attempt to start worker.
// Return bool not useful
// here, as true = started,
// false = already running.
_ = p.workers[i].Start()
}
}
// Stop will attempt to stop contained FnWorker{}s.
func (p *FnWorkerPool) Stop() {
// Check whether workers are
// set (is currently running).
ok := (len(p.workers) == 0)
if ok {
return
}
// Stop all running workers.
for i := range p.workers {
// return bool not useful
// here, as true = stopped,
// false = never running.
_ = p.workers[i].Stop()
}
// Unset workers slice.
p.workers = p.workers[:0]
}
// FnWorker wraps a queue.SimpleQueue{} which
// it feeds from to provide it with function
// tasks to execute. It does so in a single
// goroutine with state management utilities.
type FnWorker struct {
// Queue is the fn queue that FnWorker
// will feed from for upcoming tasks.
Queue *queue.SimpleQueue[func(context.Context)]
// internal fields.
service runners.Service
}
// Start will attempt to start the Worker{}.
func (w *FnWorker) Start() bool {
return w.service.GoRun(w.run)
}
// Stop will attempt to stop the Worker{}.
func (w *FnWorker) Stop() bool {
return w.service.Stop()
}
// run wraps process to restart on any panic.
func (w *FnWorker) run(ctx context.Context) {
if w.Queue == nil {
panic("not yet initialized")
}
log.Debugf(ctx, "%p: starting worker", w)
defer log.Debugf(ctx, "%p: stopped worker", w)
util.Must(func() { w.process(ctx) })
}
// process is the main delivery worker processing routine.
func (w *FnWorker) process(ctx context.Context) {
if w.Queue == nil {
// we perform this check here just
// to ensure the compiler knows these
// variables aren't nil in the loop,
// even if already checked by caller.
panic("not yet initialized")
}
for {
// Block until pop next func.
fn, ok := w.Queue.PopCtx(ctx)
if !ok {
return
}
// run!
fn(ctx)
}
}