allow multiple topics in mailserver requests (#1240)

* allow multiple topics in mailserver requests

* simplify topicsToBloom function

* create test topics simply from the string without hash

* add deprecated comment to MessagesRequest.Topic

services/shhext/api.go

@@ -7,6 +7,7 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
+	"math/big"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -63,8 +64,12 @@ type MessagesRequest struct {
 	Cursor string `json:"cursor"`
 
 	// Topic is a regular Whisper topic.
+	// DEPRECATED
 	Topic whisper.TopicType `json:"topic"`
 
+	// Topics is a list of Whisper topics.
+	Topics []whisper.TopicType `json:"topics"`
+
 	// SymKeyID is an ID of a symmetric key to authenticate to MailServer.
 	// It's derived from MailServer password.
 	//
@@ -427,7 +432,7 @@ func makePayload(r MessagesRequest) []byte {
 	// to
 	binary.BigEndian.PutUint32(data[4:], r.To)
 	// bloom
-	copy(data[8:], whisper.TopicToBloom(r.Topic))
+	copy(data[8:], createBloomFilter(r))
 	// limit
 	binary.BigEndian.PutUint32(data[8+whisper.BloomFilterSize:], r.Limit)
 
@@ -441,3 +446,25 @@ func makePayload(r MessagesRequest) []byte {
 
 	return append(data, cursorBytes...)
 }
+
+func createBloomFilter(r MessagesRequest) []byte {
+	if len(r.Topics) > 0 {
+		return topicsToBloom(r.Topics...)
+	}
+
+	return whisper.TopicToBloom(r.Topic)
+}
+
+func topicsToBloom(topics ...whisper.TopicType) []byte {
+	i := new(big.Int)
+	for _, topic := range topics {
+		bloom := whisper.TopicToBloom(topic)
+		i.Or(i, new(big.Int).SetBytes(bloom[:]))
+	}
+
+	combined := make([]byte, whisper.BloomFilterSize)
+	data := i.Bytes()
+	copy(combined[whisper.BloomFilterSize-len(data):], data[:])
+
+	return combined
+}

services/shhext/api_test.go

@@ -5,6 +5,8 @@ import (
 	"testing"
 	"time"
 
+	whisper "github.com/status-im/whisper/whisperv6"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
@@ -52,3 +54,44 @@ func TestMessagesRequest_setDefaults(t *testing.T) {
 		})
 	}
 }
+
+func TestTopicsToBloom(t *testing.T) {
+	t1 := stringToTopic("t1")
+	b1 := whisper.TopicToBloom(t1)
+	t2 := stringToTopic("t2")
+	b2 := whisper.TopicToBloom(t2)
+	t3 := stringToTopic("t3")
+	b3 := whisper.TopicToBloom(t3)
+
+	reqBloom := topicsToBloom(t1)
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b1))
+	assert.False(t, whisper.BloomFilterMatch(reqBloom, b2))
+	assert.False(t, whisper.BloomFilterMatch(reqBloom, b3))
+
+	reqBloom = topicsToBloom(t1, t2)
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b1))
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b2))
+	assert.False(t, whisper.BloomFilterMatch(reqBloom, b3))
+
+	reqBloom = topicsToBloom(t1, t2, t3)
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b1))
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b2))
+	assert.True(t, whisper.BloomFilterMatch(reqBloom, b3))
+}
+
+func TestCreateBloomFilter(t *testing.T) {
+	t1 := stringToTopic("t1")
+	t2 := stringToTopic("t2")
+
+	req := MessagesRequest{Topic: t1}
+	bloom := createBloomFilter(req)
+	assert.Equal(t, topicsToBloom(t1), bloom)
+
+	req = MessagesRequest{Topics: []whisper.TopicType{t1, t2}}
+	bloom = createBloomFilter(req)
+	assert.Equal(t, topicsToBloom(t1, t2), bloom)
+}
+
+func stringToTopic(s string) whisper.TopicType {
+	return whisper.BytesToTopic([]byte(s))
+}