adding.go

package khatru

import (
	"context"
	"errors"
	"fmt"

	"github.com/fiatjaf/eventstore"
	"github.com/nbd-wtf/go-nostr"
)

// AddEvent sends an event through then normal add pipeline, as if it was received from a websocket.
func (rl *Relay) AddEvent(ctx context.Context, evt *nostr.Event) (skipBroadcast bool, writeError error) {
	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	if evt == nil {
		return false, errors.New("error: event is nil")
	}

	for _, reject := range rl.RejectEvent {
		if reject, msg := reject(ctx, evt); reject {
			if msg == "" {
				return false, errors.New("blocked: no reason")
			} else {
				return false, errors.New(nostr.NormalizeOKMessage(msg, "blocked"))
			}
		}
	}

	if 20000 <= evt.Kind && evt.Kind < 30000 {
		// do not store ephemeral events
		for _, oee := range rl.OnEphemeralEvent {
			oee(ctx, evt)
		}
	} else {
		// will store
		// regular kinds are just saved directly
		if nostr.IsRegularKind(evt.Kind) {
			for _, store := range rl.StoreEvent {
				if err := store(ctx, evt); err != nil {
					switch err {
					case eventstore.ErrDupEvent:
						return true, nil
					default:
						return false, fmt.Errorf(nostr.NormalizeOKMessage(err.Error(), "error"))
					}
				}
			}
		} else {
			// otherwise it's a replaceable -- so we'll use the replacer functions if we have any
			if len(rl.ReplaceEvent) > 0 {
				for _, repl := range rl.ReplaceEvent {
					if err := repl(ctx, evt); err != nil {
						switch err {
						case eventstore.ErrDupEvent:
							return true, nil
						default:
							return false, fmt.Errorf(nostr.NormalizeOKMessage(err.Error(), "error"))
						}
					}
				}
			} else {
				// otherwise do it the manual way
				filter := nostr.Filter{Limit: 1, Kinds: []int{evt.Kind}, Authors: []string{evt.PubKey}}
				if nostr.IsAddressableKind(evt.Kind) {
					// when addressable, add the "d" tag to the filter
					filter.Tags = nostr.TagMap{"d": []string{evt.Tags.GetD()}}
				}

				// now we fetch old events and delete them
				shouldStore := true
				for _, query := range rl.QueryEvents {
					ch, err := query(ctx, filter)
					if err != nil {
						continue
					}
					for previous := range ch {
						if isOlder(previous, evt) {
							for _, del := range rl.DeleteEvent {
								del(ctx, previous)
							}
						} else {
							// we found a more recent event, so we won't delete it and also will not store this new one
							shouldStore = false
						}
					}
				}

				// store
				if shouldStore {
					for _, store := range rl.StoreEvent {
						if saveErr := store(ctx, evt); saveErr != nil {
							switch saveErr {
							case eventstore.ErrDupEvent:
								return true, nil
							default:
								return false, fmt.Errorf(nostr.NormalizeOKMessage(saveErr.Error(), "error"))
							}
						}
					}
				}
			}
		}

		for _, ons := range rl.OnEventSaved {
			ons(ctx, evt)
		}
	}

	return false, nil
}