a big bundle of conversions and other changes.

eventstore/codec/betterbinary/codec.go

@@ -0,0 +1,138 @@
+package betterbinary
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math"
+
+	"fiatjaf.com/nostr"
+)
+
+const (
+	MaxKind         = math.MaxUint16
+	MaxCreatedAt    = math.MaxUint32
+	MaxContentSize  = math.MaxUint16
+	MaxTagCount     = math.MaxUint16
+	MaxTagItemCount = math.MaxUint8
+	MaxTagItemSize  = math.MaxUint16
+)
+
+func Measure(evt nostr.Event) int {
+	n := 135 // static base
+
+	n += 2 + // tag section length
+		2 + // number of tags
+		len(evt.Tags)*3 // each tag offset + each tag item count
+	for _, tag := range evt.Tags {
+		n += len(tag) * 2 // item length for each item in this tag
+		for _, item := range tag {
+			n += len(item) // actual tag item
+		}
+	}
+
+	// content length and actual content
+	n += 2 + len(evt.Content)
+
+	return n
+}
+
+func Marshal(evt nostr.Event, buf []byte) error {
+	buf[0] = 0
+
+	if evt.Kind > MaxKind {
+		return fmt.Errorf("kind is too big: %d, max is %d", evt.Kind, MaxKind)
+	}
+	binary.LittleEndian.PutUint16(buf[1:3], uint16(evt.Kind))
+
+	if evt.CreatedAt > MaxCreatedAt {
+		return fmt.Errorf("created_at is too big: %d, max is %d", evt.CreatedAt, MaxCreatedAt)
+	}
+	binary.LittleEndian.PutUint32(buf[3:7], uint32(evt.CreatedAt))
+
+	copy(buf[7:39], evt.ID[:])
+	copy(buf[39:71], evt.PubKey[:])
+	copy(buf[71:135], evt.Sig[:])
+
+	tagBase := 135
+	// buf[135:137] (tagsSectionLength) will be set later when we know the absolute size of the tags section
+
+	ntags := len(evt.Tags)
+	if ntags > MaxTagCount {
+		return fmt.Errorf("can't encode too many tags: %d, max is %d", ntags, MaxTagCount)
+	}
+	binary.LittleEndian.PutUint16(buf[137:139], uint16(ntags))
+
+	tagOffset := 2 + 2 + ntags*2
+	for t, tag := range evt.Tags {
+		binary.LittleEndian.PutUint16(buf[tagBase+2+2+t*2:], uint16(tagOffset))
+
+		itemCount := len(tag)
+		if itemCount > MaxTagItemCount {
+			return fmt.Errorf("can't encode a tag with so many items: %d, max is %d", itemCount, MaxTagItemCount)
+		}
+		buf[tagBase+tagOffset] = uint8(itemCount)
+
+		itemOffset := 1
+		for _, item := range tag {
+			itemSize := len(item)
+			if itemSize > MaxTagItemSize {
+				return fmt.Errorf("tag item is too large: %d, max is %d", itemSize, MaxTagItemSize)
+			}
+
+			binary.LittleEndian.PutUint16(buf[tagBase+tagOffset+itemOffset:], uint16(itemSize))
+			copy(buf[tagBase+tagOffset+itemOffset+2:], []byte(item))
+			itemOffset += 2 + len(item)
+		}
+		tagOffset += itemOffset
+	}
+
+	tagsSectionLength := tagOffset
+	binary.LittleEndian.PutUint16(buf[tagBase:], uint16(tagsSectionLength))
+
+	// content
+	if contentLength := len(evt.Content); contentLength > MaxContentSize {
+		return fmt.Errorf("content is too large: %d, max is %d", contentLength, MaxContentSize)
+	} else {
+		binary.LittleEndian.PutUint16(buf[tagBase+tagsSectionLength:], uint16(contentLength))
+	}
+	copy(buf[tagBase+tagsSectionLength+2:], []byte(evt.Content))
+
+	return nil
+}
+
+func Unmarshal(data []byte, evt *nostr.Event) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = fmt.Errorf("failed to decode binary: %v", r)
+		}
+	}()
+
+	evt.Kind = uint16(binary.LittleEndian.Uint16(data[1:3]))
+	evt.CreatedAt = nostr.Timestamp(binary.LittleEndian.Uint32(data[3:7]))
+	evt.ID = nostr.ID(data[7:39])
+	evt.PubKey = nostr.PubKey(data[39:71])
+	evt.Sig = [64]byte(data[71:135])
+
+	const tagbase = 135
+	tagsSectionLength := binary.LittleEndian.Uint16(data[tagbase:])
+	ntags := binary.LittleEndian.Uint16(data[tagbase+2:])
+	evt.Tags = make(nostr.Tags, ntags)
+	for t := range evt.Tags {
+		offset := binary.LittleEndian.Uint16(data[tagbase+4+t*2:])
+		nitems := int(data[tagbase+offset])
+		tag := make(nostr.Tag, nitems)
+
+		curr := tagbase + offset + 1
+		for i := range tag {
+			length := binary.LittleEndian.Uint16(data[curr:])
+			tag[i] = string(data[curr+2 : curr+2+length])
+			curr += 2 + length
+		}
+		evt.Tags[t] = tag
+	}
+
+	contentLength := binary.LittleEndian.Uint16(data[tagbase+tagsSectionLength:])
+	evt.Content = string(data[tagbase+tagsSectionLength+2 : tagbase+tagsSectionLength+2+contentLength])
+
+	return err
+}

eventstore/codec/betterbinary/filtering.go

@@ -0,0 +1,33 @@
+package betterbinary
+
+import (
+	"encoding/binary"
+	"slices"
+)
+
+func TagMatches(evtb []byte, key string, vals []string) bool {
+	matches := make([][]byte, 0, len(vals))
+	for _, val := range vals {
+		match := append([]byte{1, 0, key[0], uint8(len(val)), 0}, val...)
+		matches = append(matches, match)
+	}
+
+	ntags := binary.LittleEndian.Uint16(evtb[137:])
+	var t uint16
+	for t = 0; t < ntags; t++ {
+		offset := int(binary.LittleEndian.Uint16(evtb[139+t*2:]))
+		nitems := evtb[135+offset]
+		if nitems >= 2 {
+			for _, match := range matches {
+				if slices.Equal(evtb[135+offset+1:135+offset+1+len(match)], match) {
+					return true
+				}
+			}
+		}
+	}
+	return false
+}
+
+func KindMatches(evtb []byte, kind uint16) bool {
+	return binary.LittleEndian.Uint16(evtb[1:3]) == kind
+}

eventstore/codec/betterbinary/filtering_test.go

@@ -0,0 +1,51 @@
+package betterbinary
+
+import (
+	"testing"
+
+	"github.com/mailru/easyjson"
+	"fiatjaf.com/nostr"
+)
+
+func TestTagFiltering(t *testing.T) {
+	for _, tc := range []struct {
+		json      string
+		tagKey    string
+		tagValues []string
+		matches   bool
+	}{
+		{
+			`{"id":"a9663055164ab8b30d9524656370c4bf93393bb051b7edf4556f40c5298dc0c7","pubkey":"ee11a5dff40c19a555f41fe42b48f00e618c91225622ae37b6c2bb67b76c4e49","created_at":1681778790,"kind":1,"sig":"4dfea1a6f73141d5691e43afc3234dbe73016db0fb207cf247e0127cc2591ee6b4be5b462272030a9bde75882aae810f359682b1b6ce6cbb97201141c576db42","content":"He got snowed in"}`,
+			"x",
+			[]string{"sadjqw", ""},
+			false,
+		},
+		{
+			`{"id":"a9663055164ab8b30d9524656370c4bf93393bb051b7edf4556f40c5298dc0c7","pubkey":"ee11a5dff40c19a555f41fe42b48f00e618c91225622ae37b6c2bb67b76c4e49","created_at":1681778790,"kind":1,"sig":"4dfea1a6f73141d5691e43afc3234dbe73016db0fb207cf247e0127cc2591ee6b4be5b462272030a9bde75882aae810f359682b1b6ce6cbb97201141c576db42","content":"He got snowed in","tags":[["client","gossip"],["p","e2ccf7cf20403f3f2a4a55b328f0de3be38558a7d5f33632fdaaefc726c1c8eb"],["e","2c86abcc98f7fd8a6750aab8df6c1863903f107206cc2d72e8afeb6c38357aed","wss://nostr-pub.wellorder.net/","root"]]}`,
+			"e",
+			[]string{"2c86abcc98f7fd8a6750aab8df6c1863903f107206cc2d72e8afeb6c38357aed"},
+			true,
+		},
+		{
+			`{"id":"3f551da67788c7aae15360d025595dc2d391f10bb7e759ee5d9b2ad7d64392e4","pubkey":"79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798","created_at":1712715433,"kind":1,"tags":[["-"],["askdasds"],["t","spam"],["t","nada"]],"content":"ggsgsgsg","sig":"43431f4cf8bd015305c2d484841e5730d261beeb375a86c57a61df3d26e820ce8d6712d2a3c89e3f2298597f14abf58079954e9e658ba59bfc2d7ce6384f25c7"}`,
+			"t",
+			[]string{"nothing", "nada"},
+			true,
+		},
+		{
+			`{"id":"3f551da67788c7aae15360d025595dc2d391f10bb7e759ee5d9b2ad7d64392e4","pubkey":"79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798","created_at":1712715433,"kind":1,"tags":[["-"],["askdasds"],["t","spam"],["t","nada"]],"content":"ggsgsgsg","sig":"43431f4cf8bd015305c2d484841e5730d261beeb375a86c57a61df3d26e820ce8d6712d2a3c89e3f2298597f14abf58079954e9e658ba59bfc2d7ce6384f25c7"}`,
+			"z",
+			[]string{"nothing", "nada"},
+			false,
+		},
+	} {
+		var evt nostr.Event
+		easyjson.Unmarshal([]byte(tc.json), &evt)
+		bin := make([]byte, Measure(evt))
+		Marshal(evt, bin)
+
+		if res := TagMatches(bin, tc.tagKey, tc.tagValues); res != tc.matches {
+			t.Fatalf("matched incorrectly: %v=>%v over %s was %v, expected %v", tc.tagKey, tc.tagValues, tc.json, res, tc.matches)
+		}
+	}
+}