feat(members): add ChannelQuery type

telegram/peers/members/channel.go

@@ -13,14 +13,15 @@ import (
 // ChannelMembers is channel Members.
 type ChannelMembers struct {
 	m       *peers.Manager
+	filter  tg.ChannelParticipantsFilterClass
 	channel peers.Channel
 }
 
 func (c *ChannelMembers) query(ctx context.Context, offset, limit int) (*tg.ChannelsChannelParticipants, error) {
 	raw := c.m.API()
 	p, err := raw.ChannelsGetParticipants(ctx, &tg.ChannelsGetParticipantsRequest{
 		Channel: c.channel.InputChannel(),
-		Filter:  &tg.ChannelParticipantsRecent{},
+		Filter:  c.filter,
 		Offset:  offset,
 		Limit:   limit,
 	})
@@ -100,7 +101,7 @@ func (c *ChannelMembers) ForEach(ctx context.Context, cb Callback) error {
 			if err != nil {
 				return errors.Wrapf(err, "get member %d", userID)
 			}
-			member := ChannelMember{
+			chm := ChannelMember{
 				parent:      c,
 				creatorDate: channelDate,
 				user:        user,
@@ -112,10 +113,10 @@ func (c *ChannelMembers) ForEach(ctx context.Context, cb Callback) error {
 				if err != nil {
 					return errors.Wrapf(err, "get inviter %d", inviterID)
 				}
-				member.inviter = inviter
+				chm.inviter = inviter
 			}
 
-			if err := cb(member); err != nil {
+			if err := cb(chm); err != nil {
 				return errors.Wrapf(err, "callback (index: %d)", i)
 			}
 		}
@@ -209,8 +210,5 @@ func (c *ChannelMembers) EditAdminRights(
 
 // Channel returns recent channel members.
 func Channel(channel peers.Channel) *ChannelMembers {
-	return &ChannelMembers{
-		m:       channel.Manager(),
-		channel: channel,
-	}
+	return ChannelQuery{Channel: channel}.Recent()
 }

telegram/peers/members/channel_query.go

@@ -0,0 +1,59 @@
+package members
+
+import (
+	"github.com/gotd/td/telegram/peers"
+	"github.com/gotd/td/tg"
+)
+
+// ChannelQuery is builder for channel members querying.
+type ChannelQuery struct {
+	Channel peers.Channel
+}
+
+func (q ChannelQuery) query(filter tg.ChannelParticipantsFilterClass) *ChannelMembers {
+	return &ChannelMembers{
+		m:       q.Channel.Manager(),
+		filter:  filter,
+		channel: q.Channel,
+	}
+}
+
+// Recent queries recent members.
+func (q ChannelQuery) Recent() *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsRecent{})
+}
+
+// Admins queries admins members.
+func (q ChannelQuery) Admins() *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsAdmins{})
+}
+
+// Kicked queries kicked members.
+func (q ChannelQuery) Kicked(query string) *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsKicked{Q: query})
+}
+
+// Bots queries bots members.
+func (q ChannelQuery) Bots() *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsBots{})
+}
+
+// Banned queries banned members.
+func (q ChannelQuery) Banned(query string) *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsBanned{Q: query})
+}
+
+// Search queries members by given name.
+func (q ChannelQuery) Search(query string) *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsSearch{Q: query})
+}
+
+// Contacts queries members that are also contacts.
+func (q ChannelQuery) Contacts(query string) *ChannelMembers {
+	return q.query(&tg.ChannelParticipantsContacts{Q: query})
+}
+
+// Custom creates query with custom filter.
+func (q ChannelQuery) Custom(filter tg.ChannelParticipantsFilterClass) *ChannelMembers {
+	return q.query(filter)
+}