83 lines
1.9 KiB
Go
83 lines
1.9 KiB
Go
package main
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"sync"
|
|
|
|
"github.com/rs/zerolog"
|
|
"github.com/uabluerail/indexer/pds"
|
|
"golang.org/x/time/rate"
|
|
"gorm.io/gorm"
|
|
)
|
|
|
|
const defaultRateLimit = 10
|
|
|
|
type Limiter struct {
|
|
mu sync.RWMutex
|
|
db *gorm.DB
|
|
limiter map[string]*rate.Limiter
|
|
}
|
|
|
|
func NewLimiter(db *gorm.DB) (*Limiter, error) {
|
|
remotes := []pds.PDS{}
|
|
|
|
if err := db.Find(&remotes).Error; err != nil {
|
|
return nil, fmt.Errorf("failed to get the list of known PDSs: %w", err)
|
|
}
|
|
|
|
l := &Limiter{
|
|
db: db,
|
|
limiter: map[string]*rate.Limiter{},
|
|
}
|
|
|
|
for _, remote := range remotes {
|
|
limit := remote.CrawlLimit
|
|
if limit == 0 {
|
|
limit = defaultRateLimit
|
|
}
|
|
l.limiter[remote.Host] = rate.NewLimiter(rate.Limit(limit), limit*2)
|
|
}
|
|
return l, nil
|
|
}
|
|
|
|
func (l *Limiter) getLimiter(name string) *rate.Limiter {
|
|
l.mu.RLock()
|
|
limiter := l.limiter[name]
|
|
l.mu.RUnlock()
|
|
|
|
if limiter != nil {
|
|
return limiter
|
|
}
|
|
|
|
limiter = rate.NewLimiter(defaultRateLimit, defaultRateLimit*2)
|
|
l.mu.Lock()
|
|
l.limiter[name] = limiter
|
|
l.mu.Unlock()
|
|
return limiter
|
|
}
|
|
|
|
func (l *Limiter) Wait(ctx context.Context, name string) error {
|
|
return l.getLimiter(name).Wait(ctx)
|
|
}
|
|
|
|
func (l *Limiter) SetLimit(ctx context.Context, name string, limit rate.Limit) {
|
|
l.getLimiter(name).SetLimit(limit)
|
|
err := l.db.Model(&pds.PDS{}).Where(&pds.PDS{Host: name}).Updates(&pds.PDS{CrawlLimit: int(limit)}).Error
|
|
if err != nil {
|
|
zerolog.Ctx(ctx).Error().Err(err).Msgf("Failed to persist rate limit change for %q: %s", name, err)
|
|
}
|
|
}
|
|
|
|
func (l *Limiter) SetAllLimits(ctx context.Context, limit rate.Limit) {
|
|
l.mu.RLock()
|
|
for name, limiter := range l.limiter {
|
|
limiter.SetLimit(limit)
|
|
err := l.db.Model(&pds.PDS{}).Where(&pds.PDS{Host: name}).Updates(&pds.PDS{CrawlLimit: int(limit)}).Error
|
|
if err != nil {
|
|
zerolog.Ctx(ctx).Error().Err(err).Msgf("Failed to persist rate limit change for %q: %s", name, err)
|
|
}
|
|
}
|
|
l.mu.RUnlock()
|
|
}
|