protocol/common/message_linkpreview.go
package common
import (
"fmt"
"net/url"
gethcrypto "github.com/ethereum/go-ethereum/crypto"
"github.com/status-im/status-go/eth-node/crypto"
"github.com/status-im/status-go/eth-node/types"
"github.com/status-im/status-go/images"
"github.com/status-im/status-go/protocol/protobuf"
)
type MakeMediaServerURLType func(msgID string, previewURL string, imageID MediaServerImageID) string
type MakeMediaServerURLMessageWrapperType func(previewURL string, imageID MediaServerImageID) string
type LinkPreviewThumbnail struct {
Width int `json:"width,omitempty"`
Height int `json:"height,omitempty"`
// Non-empty when the thumbnail is available via the media server, i.e. after
// the chat message is sent.
URL string `json:"url,omitempty"`
// Non-empty when the thumbnail payload needs to be shared with the client,
// but before it has been persisted.
DataURI string `json:"dataUri,omitempty"`
}
type LinkPreview struct {
Type protobuf.UnfurledLink_LinkType `json:"type"`
URL string `json:"url"`
Hostname string `json:"hostname"`
Title string `json:"title,omitempty"`
Description string `json:"description,omitempty"`
Favicon LinkPreviewThumbnail `json:"favicon,omitempty"`
Thumbnail LinkPreviewThumbnail `json:"thumbnail,omitempty"`
}
type StatusContactLinkPreview struct {
// PublicKey is: "0x" + hex-encoded decompressed public key.
// We keep it a string here for correct json marshalling.
PublicKey string `json:"publicKey"`
DisplayName string `json:"displayName"`
Description string `json:"description"`
Icon LinkPreviewThumbnail `json:"icon,omitempty"`
}
type StatusCommunityLinkPreview struct {
CommunityID string `json:"communityId"`
DisplayName string `json:"displayName"`
Description string `json:"description"`
MembersCount uint32 `json:"membersCount"`
Color string `json:"color"`
Icon LinkPreviewThumbnail `json:"icon,omitempty"`
Banner LinkPreviewThumbnail `json:"banner,omitempty"`
}
type StatusCommunityChannelLinkPreview struct {
ChannelUUID string `json:"channelUuid"`
Emoji string `json:"emoji"`
DisplayName string `json:"displayName"`
Description string `json:"description"`
Color string `json:"color"`
Community *StatusCommunityLinkPreview `json:"community"`
}
type StatusLinkPreview struct {
URL string `json:"url,omitempty"`
Contact *StatusContactLinkPreview `json:"contact,omitempty"`
Community *StatusCommunityLinkPreview `json:"community,omitempty"`
Channel *StatusCommunityChannelLinkPreview `json:"channel,omitempty"`
}
func (thumbnail *LinkPreviewThumbnail) IsEmpty() bool {
return thumbnail.Width == 0 &&
thumbnail.Height == 0 &&
thumbnail.URL == "" &&
thumbnail.DataURI == ""
}
func (thumbnail *LinkPreviewThumbnail) clear() {
thumbnail.Width = 0
thumbnail.Height = 0
thumbnail.URL = ""
thumbnail.DataURI = ""
}
func (thumbnail *LinkPreviewThumbnail) validateForProto() error {
if thumbnail.DataURI == "" {
if thumbnail.Width == 0 && thumbnail.Height == 0 {
return nil
}
return fmt.Errorf("dataUri is empty, but width/height are not zero")
}
if thumbnail.Width == 0 || thumbnail.Height == 0 {
return fmt.Errorf("dataUri is not empty, but width/heigth are zero")
}
return nil
}
func (thumbnail *LinkPreviewThumbnail) convertToProto() (*protobuf.UnfurledLinkThumbnail, error) {
var payload []byte
var err error
if thumbnail.DataURI != "" {
payload, err = images.GetPayloadFromURI(thumbnail.DataURI)
if err != nil {
return nil, fmt.Errorf("could not get data URI payload, url='%s': %w", thumbnail.URL, err)
}
}
return &protobuf.UnfurledLinkThumbnail{
Width: uint32(thumbnail.Width),
Height: uint32(thumbnail.Height),
Payload: payload,
}, nil
}
func (thumbnail *LinkPreviewThumbnail) loadFromProto(
input *protobuf.UnfurledLinkThumbnail,
URL string,
imageID MediaServerImageID,
makeMediaServerURL MakeMediaServerURLMessageWrapperType) {
thumbnail.clear()
thumbnail.Width = int(input.Width)
thumbnail.Height = int(input.Height)
if len(input.Payload) > 0 {
thumbnail.URL = makeMediaServerURL(URL, imageID)
}
}
func (preview *LinkPreview) validateForProto() error {
switch preview.Type {
case protobuf.UnfurledLink_IMAGE:
if preview.URL == "" {
return fmt.Errorf("empty url")
}
if err := preview.Thumbnail.validateForProto(); err != nil {
return fmt.Errorf("thumbnail is not valid for proto: %w", err)
}
return nil
default: // Validate as a link type by default.
if preview.Title == "" {
return fmt.Errorf("title is empty")
}
if preview.URL == "" {
return fmt.Errorf("url is empty")
}
if err := preview.Thumbnail.validateForProto(); err != nil {
return fmt.Errorf("thumbnail is not valid for proto: %w", err)
}
return nil
}
}
func (preview *StatusLinkPreview) validateForProto() error {
if preview.URL == "" {
return fmt.Errorf("url can't be empty")
}
// At least and only one of Contact/Community/Channel should be present in the preview
if preview.Contact != nil && preview.Community != nil {
return fmt.Errorf("both contact and community are set at the same time")
}
if preview.Community != nil && preview.Channel != nil {
return fmt.Errorf("both community and channel are set at the same time")
}
if preview.Channel != nil && preview.Contact != nil {
return fmt.Errorf("both contact and channel are set at the same time")
}
if preview.Contact == nil && preview.Community == nil && preview.Channel == nil {
return fmt.Errorf("none of contact/community/channel are set")
}
if preview.Contact != nil {
if preview.Contact.PublicKey == "" {
return fmt.Errorf("contact publicKey is empty")
}
if err := preview.Contact.Icon.validateForProto(); err != nil {
return fmt.Errorf("contact icon invalid: %w", err)
}
return nil
}
if preview.Community != nil {
return preview.Community.validateForProto()
}
if preview.Channel != nil {
if preview.Channel.ChannelUUID == "" {
return fmt.Errorf("channelUuid is empty")
}
if preview.Channel.Community == nil {
return fmt.Errorf("channel community is nil")
}
if err := preview.Channel.Community.validateForProto(); err != nil {
return fmt.Errorf("channel community is not valid: %w", err)
}
return nil
}
return nil
}
func (preview *StatusCommunityLinkPreview) validateForProto() error {
if preview == nil {
return fmt.Errorf("community preview is empty")
}
if preview.CommunityID == "" {
return fmt.Errorf("communityId is empty")
}
if err := preview.Icon.validateForProto(); err != nil {
return fmt.Errorf("community icon is invalid: %w", err)
}
if err := preview.Banner.validateForProto(); err != nil {
return fmt.Errorf("community banner is invalid: %w", err)
}
return nil
}
func (preview *StatusCommunityLinkPreview) convertToProto() (*protobuf.UnfurledStatusCommunityLink, error) {
if preview == nil {
return nil, nil
}
icon, err := preview.Icon.convertToProto()
if err != nil {
return nil, err
}
banner, err := preview.Banner.convertToProto()
if err != nil {
return nil, err
}
communityID, err := types.DecodeHex(preview.CommunityID)
if err != nil {
return nil, fmt.Errorf("failed to decode community id: %w", err)
}
community := &protobuf.UnfurledStatusCommunityLink{
CommunityId: communityID,
DisplayName: preview.DisplayName,
Description: preview.Description,
MembersCount: preview.MembersCount,
Color: preview.Color,
Icon: icon,
Banner: banner,
}
return community, nil
}
func (preview *StatusCommunityLinkPreview) loadFromProto(c *protobuf.UnfurledStatusCommunityLink,
URL string, thumbnailPrefix MediaServerImageIDPrefix,
makeMediaServerURL MakeMediaServerURLMessageWrapperType) {
preview.CommunityID = types.EncodeHex(c.CommunityId)
preview.DisplayName = c.DisplayName
preview.Description = c.Description
preview.MembersCount = c.MembersCount
preview.Color = c.Color
preview.Icon.clear()
preview.Banner.clear()
if icon := c.GetIcon(); icon != nil {
preview.Icon.loadFromProto(icon, URL, CreateImageID(thumbnailPrefix, MediaServerIconPostfix), makeMediaServerURL)
}
if banner := c.GetBanner(); banner != nil {
preview.Banner.loadFromProto(banner, URL, CreateImageID(thumbnailPrefix, MediaServerBannerPostfix), makeMediaServerURL)
}
}
// ConvertLinkPreviewsToProto expects previews to be correctly sent by the
// client because we can't attempt to re-unfurl URLs at this point (it's
// actually undesirable). We run a basic validation as an additional safety net.
func (m *Message) ConvertLinkPreviewsToProto() ([]*protobuf.UnfurledLink, error) {
if len(m.LinkPreviews) == 0 {
return nil, nil
}
unfurledLinks := make([]*protobuf.UnfurledLink, 0, len(m.LinkPreviews))
for _, preview := range m.LinkPreviews {
// Do not process subsequent previews because we do expect all previews to
// be valid at this stage.
if err := preview.validateForProto(); err != nil {
return nil, fmt.Errorf("invalid link preview, url='%s': %w", preview.URL, err)
}
var thumbnailPayload []byte
var faviconPayload []byte
var err error
if preview.Thumbnail.DataURI != "" {
thumbnailPayload, err = images.GetPayloadFromURI(preview.Thumbnail.DataURI)
if err != nil {
return nil, fmt.Errorf("could not get data URI payload for link preview thumbnail, url='%s': %w", preview.URL, err)
}
}
if preview.Favicon.DataURI != "" {
faviconPayload, err = images.GetPayloadFromURI(preview.Favicon.DataURI)
if err != nil {
return nil, fmt.Errorf("could not get data URI payload for link preview favicon, url='%s': %w", preview.URL, err)
}
}
ul := &protobuf.UnfurledLink{
Type: preview.Type,
Url: preview.URL,
Title: preview.Title,
Description: preview.Description,
ThumbnailWidth: uint32(preview.Thumbnail.Width),
ThumbnailHeight: uint32(preview.Thumbnail.Height),
ThumbnailPayload: thumbnailPayload,
FaviconPayload: faviconPayload,
}
unfurledLinks = append(unfurledLinks, ul)
}
return unfurledLinks, nil
}
func (m *Message) ConvertFromProtoToLinkPreviews(makeThumbnailMediaServerURL func(msgID string, previewURL string) string,
makeFaviconMediaServerURL func(msgID string, previewURL string) string) []LinkPreview {
var links []*protobuf.UnfurledLink
if links = m.GetUnfurledLinks(); links == nil {
return nil
}
previews := make([]LinkPreview, 0, len(links))
for _, link := range links {
parsedURL, err := url.Parse(link.Url)
var hostname string
// URL parsing in Go can fail with URLs that weren't correctly URL encoded.
// This shouldn't happen in general, but if an error happens we just reuse
// the full URL.
if err != nil {
hostname = link.Url
} else {
hostname = parsedURL.Hostname()
}
lp := LinkPreview{
Description: link.Description,
Hostname: hostname,
Title: link.Title,
Type: link.Type,
URL: link.Url,
}
mediaURL := ""
if len(link.ThumbnailPayload) > 0 {
mediaURL = makeThumbnailMediaServerURL(m.ID, link.Url)
}
if link.GetThumbnailPayload() != nil {
lp.Thumbnail.Width = int(link.ThumbnailWidth)
lp.Thumbnail.Height = int(link.ThumbnailHeight)
lp.Thumbnail.URL = mediaURL
}
faviconMediaURL := ""
if len(link.FaviconPayload) > 0 {
faviconMediaURL = makeFaviconMediaServerURL(m.ID, link.Url)
}
if link.GetFaviconPayload() != nil {
lp.Favicon.URL = faviconMediaURL
}
previews = append(previews, lp)
}
return previews
}
func (m *Message) ConvertStatusLinkPreviewsToProto() (*protobuf.UnfurledStatusLinks, error) {
if len(m.StatusLinkPreviews) == 0 {
return nil, nil
}
unfurledLinks := make([]*protobuf.UnfurledStatusLink, 0, len(m.StatusLinkPreviews))
for _, preview := range m.StatusLinkPreviews {
// We expect all previews to be valid at this stage
if err := preview.validateForProto(); err != nil {
return nil, fmt.Errorf("invalid status link preview, url='%s': %w", preview.URL, err)
}
ul := &protobuf.UnfurledStatusLink{
Url: preview.URL,
}
if preview.Contact != nil {
decompressedPublicKey, err := types.DecodeHex(preview.Contact.PublicKey)
if err != nil {
return nil, fmt.Errorf("failed to decode contact public key: %w", err)
}
publicKey, err := crypto.UnmarshalPubkey(decompressedPublicKey)
if err != nil {
return nil, fmt.Errorf("failed to unmarshal decompressed public key: %w", err)
}
compressedPublicKey := crypto.CompressPubkey(publicKey)
icon, err := preview.Contact.Icon.convertToProto()
if err != nil {
return nil, err
}
ul.Payload = &protobuf.UnfurledStatusLink_Contact{
Contact: &protobuf.UnfurledStatusContactLink{
PublicKey: compressedPublicKey,
DisplayName: preview.Contact.DisplayName,
Description: preview.Contact.Description,
Icon: icon,
},
}
}
if preview.Community != nil {
communityPreview, err := preview.Community.convertToProto()
if err != nil {
return nil, err
}
ul.Payload = &protobuf.UnfurledStatusLink_Community{
Community: communityPreview,
}
}
if preview.Channel != nil {
communityPreview, err := preview.Channel.Community.convertToProto()
if err != nil {
return nil, err
}
ul.Payload = &protobuf.UnfurledStatusLink_Channel{
Channel: &protobuf.UnfurledStatusChannelLink{
ChannelUuid: preview.Channel.ChannelUUID,
Emoji: preview.Channel.Emoji,
DisplayName: preview.Channel.DisplayName,
Description: preview.Channel.Description,
Color: preview.Channel.Color,
Community: communityPreview,
},
}
}
unfurledLinks = append(unfurledLinks, ul)
}
return &protobuf.UnfurledStatusLinks{UnfurledStatusLinks: unfurledLinks}, nil
}
func (m *Message) ConvertFromProtoToStatusLinkPreviews(makeMediaServerURL func(msgID string, previewURL string, imageID MediaServerImageID) string) []StatusLinkPreview {
if m.GetUnfurledStatusLinks() == nil {
return nil
}
links := m.UnfurledStatusLinks.GetUnfurledStatusLinks()
if links == nil {
return nil
}
// This wrapper adds the messageID to the callback
makeMediaServerURLMessageWrapper := func(previewURL string, imageID MediaServerImageID) string {
return makeMediaServerURL(m.ID, previewURL, imageID)
}
previews := make([]StatusLinkPreview, 0, len(links))
for _, link := range links {
lp := StatusLinkPreview{
URL: link.Url,
}
if c := link.GetContact(); c != nil {
publicKey, err := crypto.DecompressPubkey(c.PublicKey)
if err != nil {
continue
}
lp.Contact = &StatusContactLinkPreview{
PublicKey: types.EncodeHex(gethcrypto.FromECDSAPub(publicKey)),
DisplayName: c.DisplayName,
Description: c.Description,
}
if icon := c.GetIcon(); icon != nil {
lp.Contact.Icon.loadFromProto(icon, link.Url, MediaServerContactIcon, makeMediaServerURLMessageWrapper)
}
}
if c := link.GetCommunity(); c != nil {
lp.Community = new(StatusCommunityLinkPreview)
lp.Community.loadFromProto(c, link.Url, MediaServerCommunityPrefix, makeMediaServerURLMessageWrapper)
}
if c := link.GetChannel(); c != nil {
lp.Channel = &StatusCommunityChannelLinkPreview{
ChannelUUID: c.ChannelUuid,
Emoji: c.Emoji,
DisplayName: c.DisplayName,
Description: c.Description,
Color: c.Color,
}
if c.Community != nil {
lp.Channel.Community = new(StatusCommunityLinkPreview)
lp.Channel.Community.loadFromProto(c.Community, link.Url, MediaServerChannelCommunityPrefix, makeMediaServerURLMessageWrapper)
}
}
previews = append(previews, lp)
}
return previews
}