added a channels package docstring

channels/errors.go

@@ -18,4 +18,6 @@ var (
 		"the passed message is too long")
 	WrongPrivateKey = errors.New(
 		"the passed private key does not match the channel")
+	MessageTypeAlreadyRegistered = errors.New("the given message type has " +
+		"already been registered")
 )

channels/eventModel.go

@@ -8,7 +8,6 @@
 package channels
 
 import (
-	"errors"
 	"github.com/golang/protobuf/proto"
 	jww "github.com/spf13/jwalterweatherman"
 	"gitlab.com/elixxir/client/cmix/identity/receptionID"
@@ -22,13 +21,10 @@ import (
 	"gitlab.com/xx_network/primitives/id"
 )
 
+// AdminUsername defines the displayed username of admin messages, which are
+// unique users for every channel defined by the channel's private key
 const AdminUsername = "Admin"
 
-var (
-	MessageTypeAlreadyRegistered = errors.New("the given message type has " +
-		"already been registered")
-)
-
 // EventModel is an interface which an external party which uses the channels
 // system passed an object which adheres to in order to get events on the channel
 type EventModel interface {
@@ -72,6 +68,8 @@ type EventModel interface {
 	//UnPinMessage(ChannelID *id.ID, MessageID cryptoChannel.MessageID)
 }
 
+// MessageTypeReceiveMessage defines handlers for messages of various message
+// types. Default ones for Text, Reaction, and AdminText.
 type MessageTypeReceiveMessage func(channelID *id.ID,
 	messageID cryptoChannel.MessageID, messageType MessageType,
 	senderUsername string, content []byte, timestamp time.Time,

channels/interface.go

@@ -17,6 +17,10 @@ import (
 	"time"
 )
 
+// ValidForever is used as a validUntil lease when sending to denote the
+// message or operation never expires. Note: A message relay must be
+// present to enforce this otherwise things expire after 3 weeks due to
+// network retention.
 var ValidForever = time.Duration(math.MaxInt64)
 
 type Manager interface {

channels/manager.go

@@ -5,6 +5,9 @@
 // LICENSE file                                                               //
 ////////////////////////////////////////////////////////////////////////////////
 
+// Package channels provides a channels implementation on top of broadcast
+// which is capable of handing the user facing features of channels, including
+// replies, reactions, and eventually admin commands.
 package channels
 
 import (