Add mqtt/packet/pubrel.go

mqtt/packet/pubrel.go

@@ -0,0 +1,50 @@
+package packet
+
+// puback represents a PUBACK Packet.
+type pubrel struct {
+	base
+	// packetID is the Packet Identifier of the variable header.
+	packetID uint16
+}
+
+// PacketID returns the Packet Identifier of the Packet.
+func (p *pubrel) PacketID() uint16 {
+	return p.packetID
+}
+
+// setFixedHeader sets the fixed header to the Packet.
+func (p *pubrel) setFixedHeader() {
+	// Append the first byte to the fixed header.
+	p.fixedHeader = append(p.fixedHeader, TypePUBREL<<4|0x02)
+
+	// Append the Remaining Length to the fixed header.
+	p.appendRemainingLength()
+}
+
+// setVariableHeader sets the variable header to the Packet.
+func (p *pubrel) setVariableHeader() {
+	// Append the Packet Identifier to the variable header.
+	p.variableHeader = append(p.variableHeader, encodeUint16(p.packetID)...)
+}
+
+// NewPUBREL creates and returns a PUBREL Packet.
+func NewPUBREL(opts *PUBRELOptions) Packet {
+	// Initialize the options.
+	if opts == nil {
+		opts = &PUBRELOptions{}
+	}
+
+	// Create a PUBREL Packet.
+	p := &pubrel{
+		packetID: opts.PacketID,
+	}
+
+	// Set the variable header to the Packet.
+	p.setVariableHeader()
+
+	// Set the Fixed header to the Packet.
+	p.setFixedHeader()
+
+	// Return the Packet.
+	return p
+}

mqtt/packet/pubrel_options.go

@@ -0,0 +1,7 @@
+package packet
+
+// PUBRELOptions represents options for a PUBREL Packet.
+type PUBRELOptions struct {
+	// PacketID is the Packet Identifier of the variable header.
+	PacketID uint16
+}

mqtt/packet/pubrel_test.go

@@ -0,0 +1,62 @@
+package packet
+
+import "testing"
+
+func Test_pubrel_PacketID(t *testing.T) {
+	want := uint16(1)
+
+	p := &pubrel{
+		packetID: want,
+	}
+
+	if got := p.PacketID(); got != want {
+		t.Errorf("got => %d, want => %d", got, want)
+	}
+}
+
+func Test_pubrel_setFixedHeader(t *testing.T) {
+	p := &pubrel{
+		packetID: 1,
+	}
+
+	p.variableHeader = []byte{0x00, 0x01}
+
+	p.setFixedHeader()
+
+	want := []byte{
+		TypePUBREL<<4 | 0x02,
+		byte(len(p.variableHeader)),
+	}
+
+	if len(p.fixedHeader) != len(want) || p.fixedHeader[0] != want[0] || p.fixedHeader[1] != want[1] {
+		t.Errorf("p.fixedHeader => %v, want => %v", p.fixedHeader, want)
+	}
+}
+
+func Test_pubrel_setVariableHeader(t *testing.T) {
+	p := &pubrel{
+		packetID: 65534,
+	}
+
+	p.setVariableHeader()
+
+	want := []byte{0xFF, 0xFE}
+
+	if len(p.variableHeader) != len(want) || p.variableHeader[0] != want[0] || p.variableHeader[1] != want[1] {
+		t.Errorf("p.variableHeader => %v, want => %v", p.variableHeader, want)
+	}
+}
+
+func TestNewPUBREL(t *testing.T) {
+	p := NewPUBREL(nil)
+
+	ptype, err := p.Type()
+	if err != nil {
+		nilErrorExpected(t, err)
+		return
+	}
+
+	if ptype != TypePUBREL {
+		t.Errorf("ptype => %X, want => %X", ptype, TypePUBREL)
+	}
+}