2 - Broadcast - Datatypes

broadcast/dtos/dtos.go

@@ -0,0 +1,86 @@
+// Package dtos implements all data transfer objects used from outside the broadcast implementation context.
+package dtos
+
+import (
+	"context"
+	"google.golang.org/protobuf/reflect/protoreflect"
+	"time"
+)
+
+// Msg defines the message sent from a server to another server or client. The messages should be sent by the router.
+type Msg interface {
+	GetBroadcastID() uint64
+	GetMethod() string
+	String() string
+}
+
+// BroadcastMsg is a data transfer object of a message received by another server or client.
+type BroadcastMsg struct {
+	Ctx     context.Context
+	Options BroadcastOptions
+	// The address of the client or server that originated the broadcast request
+	OriginAddr string
+	Info       Info
+}
+
+func (msg *BroadcastMsg) GetBroadcastID() uint64 {
+	return msg.Info.BroadcastID
+}
+
+func (msg *BroadcastMsg) GetMethod() string {
+	return msg.Info.Method
+}
+
+func (msg *BroadcastMsg) String() string {
+	return "broadcast"
+}
+
+// ReplyMsg is similar to BroadcastMsg, but is strictly used for replying to a client.
+type ReplyMsg struct {
+	Info Info
+	// The address of the client that originated the broadcast request
+	ClientAddr string
+	Err        error
+}
+
+func (r *ReplyMsg) GetBroadcastID() uint64 {
+	return r.Info.BroadcastID
+}
+
+func (r *ReplyMsg) GetMethod() string {
+	return "reply"
+}
+
+func (r *ReplyMsg) String() string {
+	return "reply"
+}
+
+// Info contains data pertaining to the current message such as routing information, contents, and which server handler
+// should receive the message.
+type Info struct {
+	Message         protoreflect.ProtoMessage
+	BroadcastID     uint64
+	Method          string
+	Addr            string
+	OriginMethod    string
+	OriginDigest    []byte
+	OriginSignature []byte
+	OriginPubKey    string
+}
+
+// Client is a data structure used when sending a reply to a client.
+type Client struct {
+	Addr    string
+	SendMsg func(timeout time.Duration, dto *ReplyMsg) error
+	Close   func() error
+}
+
+// BroadcastOptions is used to configure a particular broadcast, e.g. by only broadcasting to a subset of the servers in
+// a view.
+type BroadcastOptions struct {
+	ServerAddresses  []string
+	AllowDuplication bool
+	SkipSelf         bool
+	ProgressTo       string
+	RelatedToReq     uint64
+}

broadcast/errors/errors.go

@@ -0,0 +1,49 @@
+package errors
+
+// IDErr should be used when a message with a BroadcastID is sent to a broadcast processor with another BroadcastID. This
+// can happen if a user deliberately changes the BroadcastID of a message.
+type IDErr struct{}
+
+func (err IDErr) Error() string {
+	return "broadcast: wrong ID"
+}
+
+// MissingClientReqErr signifies that a server tries to reply to a client, but has not yet received the original request
+// form the client. This is especially important when the message does not contain routing information, such as in QuorumCalls.
+type MissingClientReqErr struct{}
+
+func (err MissingClientReqErr) Error() string {
+	return "broadcast: has not received client req yet"
+}
+
+// AlreadyProcessedErr is used when a message is received after the broadcast processor has stopped. This means that the
+// server has sent a reply to the client and thus the incoming message needs not be processed.
+type AlreadyProcessedErr struct{}
+
+func (err AlreadyProcessedErr) Error() string {
+	return "broadcast: already processed request"
+}
+
+// ClientReqAlreadyReceivedErr should be used when a duplicate client request is received.
+type ClientReqAlreadyReceivedErr struct{}
+
+func (err ClientReqAlreadyReceivedErr) Error() string {
+	return "broadcast: client request already received (dropped)"
+}
+
+// OutOfOrderErr should be used when the preserve ordering configuration option is used and a message is received out of
+// order.
+type OutOfOrderErr struct{}
+
+func (err OutOfOrderErr) Error() string {
+	return "broadcast: the message is out of order"
+}
+
+// InvalidAddrErr should be used when an invalid server/client address is provided.
+type InvalidAddrErr struct {
+	Addr string
+}
+
+func (err InvalidAddrErr) Error() string {
+	return "broadcast: provided Addr is invalid. got: " + err.Addr
+}

examples/go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510
 	github.com/relab/gorums v0.7.0
 	golang.org/x/term v0.18.0
-	google.golang.org/grpc v1.62.1
+	google.golang.org/grpc v1.63.0
 	google.golang.org/protobuf v1.33.0
 )
 

examples/go.sum

@@ -22,6 +22,7 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20240318140521-94a12d6c2237 h1:
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240318140521-94a12d6c2237/go.mod h1:WtryC6hu0hhx87FDGxWCDptyssuo68sk10vYjF+T9fY=
 google.golang.org/grpc v1.62.1 h1:B4n+nfKzOICUXMgyrNd19h/I9oH0L1pizfk1d4zSgTk=
 google.golang.org/grpc v1.62.1/go.mod h1:IWTG0VlJLCh1SkC58F7np9ka9mx/WNkjl4PGJaiq+QE=
+google.golang.org/grpc v1.63.0/go.mod h1:WAX/8DgncnokcFUldAxq7GeB5DXHDbMF+lLvDomNkRA=
 google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.3.0 h1:rNBFJjBCOgVr9pWD7rs/knKL4FRTKgpZmsRfV214zcA=
 google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.3.0/go.mod h1:Dk1tviKTvMCz5tvh7t+fh94dhmQVHuCt2OzJB3CTW9Y=
 google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=