Support extra attributes in Join. (#684)

Author: dennwc

room.go

@@ -98,6 +98,8 @@ type SignalClientConnectParams struct {
 
 	RetransmitBufferSize uint16
 
+	Attributes map[string]string // See WithExtraAttributes
+
 	Pacer pacer.Factory
 
 	Interceptors []interceptor.Factory
@@ -147,6 +149,20 @@ func WithDisableRegionDiscovery() ConnectOption {
 	}
 }
 
+func WithExtraAttributes(attrs map[string]string) ConnectOption {
+	return func(p *SignalClientConnectParams) {
+		if len(attrs) != 0 && p.Attributes == nil {
+			p.Attributes = make(map[string]string, len(attrs))
+		}
+		for k, v := range attrs {
+			if v == "" {
+				continue
+			}
+			p.Attributes[k] = v
+		}
+	}
+}
+
 type PLIWriter func(webrtc.SSRC)
 
 type Room struct {

signalclient.go

@@ -16,6 +16,8 @@ package lksdk
 
 import (
 	"context"
+	"encoding/base64"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -153,6 +155,14 @@ func (c *SignalClient) connectContext(ctx context.Context, urlPrefix string, tok
 			urlSuffix += fmt.Sprintf("&sid=%s", participantSID)
 		}
 	}
+	if len(params.Attributes) != 0 {
+		data, err := json.Marshal(params.Attributes)
+		if err != nil {
+			return nil, ErrInvalidParameter
+		}
+		str := base64.URLEncoding.EncodeToString(data)
+		urlSuffix += "&attributes=" + str
+	}
 	urlSuffix += getStatsParamString()
 
 	u, err := url.Parse(urlPrefix + urlSuffix)