rssmon3/monitor/queue.go

84 lines
1.3 KiB
Go
Executable File

package monitor
import (
"fmt"
"local/rssmon3/config"
"local/storage"
"log"
"github.com/golang-collections/go-datastructures/queue"
)
const nsQueued = "nsQueued"
type Queue struct {
queue *queue.PriorityQueue
}
func newQueue() (*Queue, error) {
q := queue.NewPriorityQueue(1)
db := config.Values().DB
keys, err := db.List([]string{nsQueued})
if err == storage.ErrNotFound {
keys = []string{}
} else if err != nil {
return nil, err
}
for _, key := range keys {
b, err := db.Get(key, nsQueued)
if err != nil {
return nil, fmt.Errorf("failed to get %s:%s: %v", nsQueued, key, err)
}
i := &Item{}
if err := i.Decode(b); err != nil {
return nil, err
}
q.Put(i)
}
return &Queue{
queue: q,
}, nil
}
func (q *Queue) Push(i *Item) {
if i == nil {
return
}
q.queue.Put(i)
b, err := i.Encode()
if err != nil {
log.Println("[Push]", err)
return
}
if err := config.Values().DB.Set(i.Key, b, nsQueued); err != nil {
log.Println("[Push]", err)
return
}
}
func (q *Queue) Pop() *Item {
is, err := q.queue.Get(1)
if err != nil {
return nil
}
if len(is) < 1 {
return nil
}
if is[0] == nil {
return nil
}
return is[0].(*Item)
}
func (q *Queue) Peek() *Item {
i := q.queue.Peek()
if i == nil {
return nil
}
return i.(*Item)
}
func (q *Queue) Len() int {
return q.queue.Len()
}