158 lines
3.4 KiB
Go
158 lines
3.4 KiB
Go
package slicestore
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"strings"
|
|
"sync"
|
|
|
|
"github.com/fiatjaf/eventstore"
|
|
"github.com/fiatjaf/eventstore/internal"
|
|
"github.com/nbd-wtf/go-nostr"
|
|
"golang.org/x/exp/slices"
|
|
)
|
|
|
|
var _ eventstore.Store = (*SliceStore)(nil)
|
|
|
|
type SliceStore struct {
|
|
sync.Mutex
|
|
internal []*nostr.Event
|
|
|
|
MaxLimit int
|
|
}
|
|
|
|
func (b *SliceStore) Init() error {
|
|
b.internal = make([]*nostr.Event, 0, 5000)
|
|
if b.MaxLimit == 0 {
|
|
b.MaxLimit = 500
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (b *SliceStore) Close() {}
|
|
|
|
func (b *SliceStore) QueryEvents(ctx context.Context, filter nostr.Filter) (chan *nostr.Event, error) {
|
|
ch := make(chan *nostr.Event)
|
|
if filter.Limit > b.MaxLimit || (filter.Limit == 0 && !filter.LimitZero) {
|
|
filter.Limit = b.MaxLimit
|
|
}
|
|
|
|
// efficiently determine where to start and end
|
|
start := 0
|
|
end := len(b.internal)
|
|
if filter.Until != nil {
|
|
start, _ = slices.BinarySearchFunc(b.internal, *filter.Until, eventTimestampComparator)
|
|
}
|
|
if filter.Since != nil {
|
|
end, _ = slices.BinarySearchFunc(b.internal, *filter.Since, eventTimestampComparator)
|
|
}
|
|
|
|
// ham
|
|
if end < start {
|
|
close(ch)
|
|
return ch, nil
|
|
}
|
|
|
|
count := 0
|
|
go func() {
|
|
for _, event := range b.internal[start:end] {
|
|
if count == filter.Limit {
|
|
break
|
|
}
|
|
|
|
if filter.Matches(event) {
|
|
select {
|
|
case ch <- event:
|
|
case <-ctx.Done():
|
|
return
|
|
}
|
|
count++
|
|
}
|
|
}
|
|
close(ch)
|
|
}()
|
|
return ch, nil
|
|
}
|
|
|
|
func (b *SliceStore) CountEvents(ctx context.Context, filter nostr.Filter) (int64, error) {
|
|
var val int64
|
|
for _, event := range b.internal {
|
|
if filter.Matches(event) {
|
|
val++
|
|
}
|
|
}
|
|
return val, nil
|
|
}
|
|
|
|
func (b *SliceStore) SaveEvent(ctx context.Context, evt *nostr.Event) error {
|
|
idx, found := slices.BinarySearchFunc(b.internal, evt, eventComparator)
|
|
if found {
|
|
return eventstore.ErrDupEvent
|
|
}
|
|
// let's insert at the correct place in the array
|
|
b.internal = append(b.internal, evt) // bogus
|
|
copy(b.internal[idx+1:], b.internal[idx:])
|
|
b.internal[idx] = evt
|
|
|
|
return nil
|
|
}
|
|
|
|
func (b *SliceStore) DeleteEvent(ctx context.Context, evt *nostr.Event) error {
|
|
idx, found := slices.BinarySearchFunc(b.internal, evt, eventComparator)
|
|
if !found {
|
|
// we don't have this event
|
|
return nil
|
|
}
|
|
|
|
// we have it
|
|
copy(b.internal[idx:], b.internal[idx+1:])
|
|
b.internal = b.internal[0 : len(b.internal)-1]
|
|
return nil
|
|
}
|
|
|
|
func (b *SliceStore) ReplaceEvent(ctx context.Context, evt *nostr.Event) error {
|
|
b.Lock()
|
|
defer b.Unlock()
|
|
|
|
filter := nostr.Filter{Limit: 1, Kinds: []int{evt.Kind}, Authors: []string{evt.PubKey}}
|
|
if nostr.IsAddressableKind(evt.Kind) {
|
|
filter.Tags = nostr.TagMap{"d": []string{evt.Tags.GetD()}}
|
|
}
|
|
|
|
ch, err := b.QueryEvents(ctx, filter)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to query before replacing: %w", err)
|
|
}
|
|
|
|
shouldStore := true
|
|
for previous := range ch {
|
|
if internal.IsOlder(previous, evt) {
|
|
if err := b.DeleteEvent(ctx, previous); err != nil {
|
|
return fmt.Errorf("failed to delete event for replacing: %w", err)
|
|
}
|
|
} else {
|
|
shouldStore = false
|
|
}
|
|
}
|
|
|
|
if shouldStore {
|
|
if err := b.SaveEvent(ctx, evt); err != nil && err != eventstore.ErrDupEvent {
|
|
return fmt.Errorf("failed to save: %w", err)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func eventTimestampComparator(e *nostr.Event, t nostr.Timestamp) int {
|
|
return int(t) - int(e.CreatedAt)
|
|
}
|
|
|
|
func eventComparator(a *nostr.Event, b *nostr.Event) int {
|
|
c := int(b.CreatedAt) - int(a.CreatedAt)
|
|
if c != 0 {
|
|
return c
|
|
}
|
|
return strings.Compare(b.ID, a.ID)
|
|
}
|