lnwire: refactor Encode to use specific writers - I

This commit takes 10 types of messages and refactors their Encode method
to use specific writers. The following commits will refactor the rest.

lnwire/accept_channel.go

@@ -126,23 +126,63 @@ func (a *AcceptChannel) Encode(w *bytes.Buffer, pver uint32) error {
 		return err
 	}
 
-	return WriteElements(w,
-		a.PendingChannelID[:],
-		a.DustLimit,
-		a.MaxValueInFlight,
-		a.ChannelReserve,
-		a.HtlcMinimum,
-		a.MinAcceptDepth,
-		a.CsvDelay,
-		a.MaxAcceptedHTLCs,
-		a.FundingKey,
-		a.RevocationPoint,
-		a.PaymentPoint,
-		a.DelayedPaymentPoint,
-		a.HtlcPoint,
-		a.FirstCommitmentPoint,
-		tlvRecords,
-	)
+	if err := WriteBytes(w, a.PendingChannelID[:]); err != nil {
+		return err
+	}
+
+	if err := WriteSatoshi(w, a.DustLimit); err != nil {
+		return err
+	}
+
+	if err := WriteMilliSatoshi(w, a.MaxValueInFlight); err != nil {
+		return err
+	}
+
+	if err := WriteSatoshi(w, a.ChannelReserve); err != nil {
+		return err
+	}
+
+	if err := WriteMilliSatoshi(w, a.HtlcMinimum); err != nil {
+		return err
+	}
+
+	if err := WriteUint32(w, a.MinAcceptDepth); err != nil {
+		return err
+	}
+
+	if err := WriteUint16(w, a.CsvDelay); err != nil {
+		return err
+	}
+
+	if err := WriteUint16(w, a.MaxAcceptedHTLCs); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.FundingKey); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.RevocationPoint); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.PaymentPoint); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.DelayedPaymentPoint); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.HtlcPoint); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, a.FirstCommitmentPoint); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, tlvRecords)
 }
 
 // Decode deserializes the serialized AcceptChannel stored in the passed

lnwire/announcement_signatures.go

@@ -66,13 +66,23 @@ func (a *AnnounceSignatures) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (a *AnnounceSignatures) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		a.ChannelID,
-		a.ShortChannelID,
-		a.NodeSignature,
-		a.BitcoinSignature,
-		a.ExtraOpaqueData,
-	)
+	if err := WriteChannelID(w, a.ChannelID); err != nil {
+		return err
+	}
+
+	if err := WriteShortChannelID(w, a.ShortChannelID); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, a.NodeSignature); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, a.BitcoinSignature); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, a.ExtraOpaqueData)
 }
 
 // MsgType returns the integer uniquely identifying this message type on the

lnwire/closing_signed.go

@@ -65,9 +65,19 @@ func (c *ClosingSigned) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (c *ClosingSigned) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(
-		w, c.ChannelID, c.FeeSatoshis, c.Signature, c.ExtraData,
-	)
+	if err := WriteChannelID(w, c.ChannelID); err != nil {
+		return err
+	}
+
+	if err := WriteSatoshi(w, c.FeeSatoshis); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, c.Signature); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, c.ExtraData)
 }
 
 // MsgType returns the integer uniquely identifying this message type on the

lnwire/commit_sig.go

@@ -71,12 +71,19 @@ func (c *CommitSig) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (c *CommitSig) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		c.ChanID,
-		c.CommitSig,
-		c.HtlcSigs,
-		c.ExtraData,
-	)
+	if err := WriteChannelID(w, c.ChanID); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, c.CommitSig); err != nil {
+		return err
+	}
+
+	if err := WriteSigs(w, c.HtlcSigs); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, c.ExtraData)
 }
 
 // MsgType returns the integer uniquely identifying this message type on the

lnwire/error.go

@@ -105,10 +105,11 @@ func (c *Error) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (c *Error) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		c.ChanID,
-		c.Data,
-	)
+	if err := WriteBytes(w, c.ChanID[:]); err != nil {
+		return err
+	}
+
+	return WriteErrorData(w, c.Data)
 }
 
 // MsgType returns the integer uniquely identifying an Error message on the

lnwire/funding_created.go

@@ -42,10 +42,19 @@ var _ Message = (*FundingCreated)(nil)
 //
 // This is part of the lnwire.Message interface.
 func (f *FundingCreated) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(
-		w, f.PendingChannelID[:], f.FundingPoint, f.CommitSig,
-		f.ExtraData,
-	)
+	if err := WriteBytes(w, f.PendingChannelID[:]); err != nil {
+		return err
+	}
+
+	if err := WriteOutPoint(w, f.FundingPoint); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, f.CommitSig); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, f.ExtraData)
 }
 
 // Decode deserializes the serialized FundingCreated stored in the passed

lnwire/funding_locked.go

@@ -60,11 +60,15 @@ func (c *FundingLocked) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (c *FundingLocked) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		c.ChanID,
-		c.NextPerCommitmentPoint,
-		c.ExtraData,
-	)
+	if err := WriteChannelID(w, c.ChanID); err != nil {
+		return err
+	}
+
+	if err := WritePublicKey(w, c.NextPerCommitmentPoint); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, c.ExtraData)
 }
 
 // MsgType returns the uint32 code which uniquely identifies this message as a

lnwire/funding_signed.go

@@ -33,7 +33,15 @@ var _ Message = (*FundingSigned)(nil)
 //
 // This is part of the lnwire.Message interface.
 func (f *FundingSigned) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w, f.ChanID, f.CommitSig, f.ExtraData)
+	if err := WriteChannelID(w, f.ChanID); err != nil {
+		return err
+	}
+
+	if err := WriteSig(w, f.CommitSig); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, f.ExtraData)
 }
 
 // Decode deserializes the serialized FundingSigned stored in the passed

lnwire/gossip_timestamp_range.go

@@ -59,12 +59,19 @@ func (g *GossipTimestampRange) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (g *GossipTimestampRange) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		g.ChainHash[:],
-		g.FirstTimestamp,
-		g.TimestampRange,
-		g.ExtraData,
-	)
+	if err := WriteBytes(w, g.ChainHash[:]); err != nil {
+		return err
+	}
+
+	if err := WriteUint32(w, g.FirstTimestamp); err != nil {
+		return err
+	}
+
+	if err := WriteUint32(w, g.TimestampRange); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, g.ExtraData)
 }
 
 // MsgType returns the integer uniquely identifying this message type on the

lnwire/init_message.go

@@ -60,11 +60,15 @@ func (msg *Init) Decode(r io.Reader, pver uint32) error {
 //
 // This is part of the lnwire.Message interface.
 func (msg *Init) Encode(w *bytes.Buffer, pver uint32) error {
-	return WriteElements(w,
-		msg.GlobalFeatures,
-		msg.Features,
-		msg.ExtraData,
-	)
+	if err := WriteRawFeatureVector(w, msg.GlobalFeatures); err != nil {
+		return err
+	}
+
+	if err := WriteRawFeatureVector(w, msg.Features); err != nil {
+		return err
+	}
+
+	return WriteBytes(w, msg.ExtraData)
 }
 
 // MsgType returns the integer uniquely identifying this message type on the