Fix encoding for float64 and generate conversion for Timestamp

- fixes encoding/decoding of float64 - uses little endian (contrary to all other types)
- generates helper methods for vpe_types.Timestamp type
- adds usage code to simple-client and binapi-types examples

Change-Id: I2e83eee0629eb67964049406c50c7ee0a692ccaf
Signed-off-by: Ondrej Fabry <ofabry@cisco.com>

7 files changed, 142 insertions, 26 deletions

diff --git a/binapi/vpe_types/vpe_types.ba.go b/binapi/vpe_types/vpe_types.ba.go
index 473880d..b4d324f 100644
--- a/binapi/vpe_types/vpe_types.ba.go
+++ b/binapi/vpe_types/vpe_types.ba.go
@@ -15,6 +15,7 @@ package vpe_types
 
 import (
 	"strconv"
+	"time"
 
 	api "git.fd.io/govpp.git/api"
 )
@@ -79,6 +80,33 @@ type Timedelta float64
 // Timestamp defines alias 'timestamp'.
 type Timestamp float64
 
+func NewTimestamp(t time.Time) Timestamp {
+	sec := int64(t.Unix())
+	nsec := int32(t.Nanosecond())
+	ns := float64(sec) + float64(nsec/1e9)
+	return Timestamp(ns)
+}
+func (x Timestamp) ToTime() time.Time {
+	ns := int64(x * 1e9)
+	sec := ns / 1e9
+	nsec := ns % 1e9
+	return time.Unix(sec, nsec)
+}
+func (x Timestamp) String() string {
+	return x.ToTime().String()
+}
+func (x *Timestamp) MarshalText() ([]byte, error) {
+	return []byte(x.ToTime().Format(time.RFC3339Nano)), nil
+}
+func (x *Timestamp) UnmarshalText(text []byte) error {
+	t, err := time.Parse(time.RFC3339Nano, string(text))
+	if err != nil {
+		return err
+	}
+	*x = NewTimestamp(t)
+	return nil
+}
+
 // Version defines type 'version'.
 type Version struct {
 	Major         uint32 `binapi:"u32,name=major" json:"major,omitempty"`
diff --git a/binapigen/gen_helpers.go b/binapigen/gen_helpers.go
index 5eafc76..944bfe2 100644
--- a/binapigen/gen_helpers.go
+++ b/binapigen/gen_helpers.go
@@ -22,6 +22,7 @@ func init() {
 const (
 	fmtPkg     = GoImportPath("fmt")
 	netPkg     = GoImportPath("net")
+	timePkg    = GoImportPath("time")
 	stringsPkg = GoImportPath("strings")
 )
 
@@ -185,13 +186,6 @@ func genIPPrefixConversion(g *GenFile, structName string, ipv int) {
 	g.P("func (x ", structName, ") String() string {")
 	g.P("	ip := x.Address.String()")
 	g.P("	return ip + \"/\" + ", strconvPkg.Ident("Itoa"), "(int(x.Len))")
-	/*if ipv == 4 {
-	  	g.P("	mask := ", netPkg.Ident("CIDRMask"), "(int(x.Len), 32)")
-	  } else {
-	  	g.P("	mask := ", netPkg.Ident("CIDRMask"), "(int(x.Len), 128)")
-	  }
-	  g.P("	ipnet := &", netPkg.Ident("IPNet"), "{IP: x.Address.ToIP(), Mask: mask}")
-	  g.P("	return ipnet.String()")*/
 	g.P("}")
 
 	// MarshalText method
@@ -346,3 +340,42 @@ func genMacAddressConversion(g *GenFile, structName string) {
 	g.P("}")
 	g.P()
 }
+
+func genTimestampConversion(g *GenFile, structName string) {
+	// NewTimestamp method
+	g.P("func New", structName, "(t ", timePkg.Ident("Time"), ") ", structName, " {")
+	g.P("	sec := int64(t.Unix())")
+	g.P("	nsec := int32(t.Nanosecond())")
+	g.P("	ns := float64(sec) + float64(nsec / 1e9)")
+	g.P("	return ", structName, "(ns)")
+	g.P("}")
+
+	// ToTime method
+	g.P("func (x ", structName, ") ToTime() ", timePkg.Ident("Time"), " {")
+	g.P("	ns := int64(x * 1e9)")
+	g.P("	sec := ns / 1e9")
+	g.P("	nsec := ns % 1e9")
+	g.P("	return ", timePkg.Ident("Unix"), "(sec, nsec)")
+	g.P("}")
+
+	// String method
+	g.P("func (x ", structName, ") String() string {")
+	g.P("	return x.ToTime().String()")
+	g.P("}")
+
+	// MarshalText method
+	g.P("func (x *", structName, ") MarshalText() ([]byte, error) {")
+	g.P("	return []byte(x.ToTime().Format(", timePkg.Ident("RFC3339Nano"), ")), nil")
+	g.P("}")
+
+	// UnmarshalText method
+	g.P("func (x *", structName, ") UnmarshalText(text []byte) error {")
+	g.P("	t, err := ", timePkg.Ident("Parse"), "(", timePkg.Ident("RFC3339Nano"), ", string(text))")
+	g.P("	if err != nil {")
+	g.P("		return err")
+	g.P("	}")
+	g.P("	*x = New", structName, "(t)")
+	g.P("	return nil")
+	g.P("}")
+	g.P()
+}
diff --git a/binapigen/gen_helpers_test.go b/binapigen/gen_helpers_test.go
index 371fd6c..075dd8e 100644
--- a/binapigen/gen_helpers_test.go
+++ b/binapigen/gen_helpers_test.go
@@ -17,11 +17,13 @@ package binapigen
 import (
 	"strings"
 	"testing"
+	"time"
 
 	. "github.com/onsi/gomega"
 
 	"git.fd.io/govpp.git/binapi/ethernet_types"
 	"git.fd.io/govpp.git/binapi/ip_types"
+	"git.fd.io/govpp.git/binapi/vpe_types"
 )
 
 func TestGeneratedParseAddress(t *testing.T) {
@@ -154,3 +156,28 @@ func TestGeneratedParseMACError(t *testing.T) {
 	_, err := ethernet_types.ParseMacAddress("malformed_mac")
 	Expect(err).Should(HaveOccurred())
 }
+
+func TestGeneratedParseTimestamp(t *testing.T) {
+	RegisterTestingT(t)
+
+	var data = []struct {
+		input  time.Time
+		result vpe_types.Timestamp
+	}{
+		{time.Unix(0, 0), vpe_types.Timestamp(0)},
+		{time.Date(2000, 1, 1, 0, 0, 0, 0, time.UTC),
+			vpe_types.Timestamp(9.466848e+08)},
+	}
+
+	for _, entry := range data {
+		t.Run(entry.input.String(), func(t *testing.T) {
+			ts := vpe_types.NewTimestamp(entry.input)
+			Expect(ts).To(Equal(entry.result))
+
+			Expect(entry.input.Equal(ts.ToTime())).To(BeTrue())
+
+			originTime := ts.String()
+			Expect(originTime).To(Equal(entry.input.Local().String()))
+		})
+	}
+}
diff --git a/binapigen/generate.go b/binapigen/generate.go
index 834c989..bf6df81 100644
--- a/binapigen/generate.go
+++ b/binapigen/generate.go
@@ -246,6 +246,8 @@ func genAlias(g *GenFile, alias *Alias) {
 		genAddressWithPrefixConversion(g, alias.GoName)
 	case "mac_address":
 		genMacAddressConversion(g, alias.GoName)
+	case "timestamp":
+		genTimestampConversion(g, alias.GoName)
 	}
 }
 
diff --git a/codec/codec.go b/codec/codec.go
index 3ae578b..21354a1 100644
--- a/codec/codec.go
+++ b/codec/codec.go
@@ -156,12 +156,12 @@ func (b *Buffer) DecodeInt64() int64 {
 }
 
 func (b *Buffer) EncodeFloat64(v float64) {
-	binary.BigEndian.PutUint64(b.buf[b.pos:b.pos+8], math.Float64bits(v))
+	binary.LittleEndian.PutUint64(b.buf[b.pos:b.pos+8], math.Float64bits(v))
 	b.pos += 8
 }
 
 func (b *Buffer) DecodeFloat64() float64 {
-	v := math.Float64frombits(binary.BigEndian.Uint64(b.buf[b.pos : b.pos+8]))
+	v := math.Float64frombits(binary.LittleEndian.Uint64(b.buf[b.pos : b.pos+8]))
 	b.pos += 8
 	return v
 }
diff --git a/examples/binapi-types/binapi_types.go b/examples/binapi-types/binapi_types.go
index 849ad1b..2dbaa3e 100644
--- a/examples/binapi-types/binapi_types.go
+++ b/examples/binapi-types/binapi_types.go
@@ -18,36 +18,42 @@ package main
 import (
 	"fmt"
 	"log"
+	"time"
 
 	"git.fd.io/govpp.git/binapi/ethernet_types"
 	"git.fd.io/govpp.git/binapi/ip"
 	"git.fd.io/govpp.git/binapi/ip_types"
+	"git.fd.io/govpp.git/binapi/vpe_types"
 	"git.fd.io/govpp.git/codec"
 )
 
 func init() {
-	log.SetFlags(0)
 }
 
 func main() {
-	addressUnionExample()
-	ipAddressExample()
+	log.SetFlags(0)
+
+	usageUnion()
+	usageAddress()
 
-	// convert IP from string form into Address type containing union
-	convertIP("10.10.1.1")
-	convertIP("ff80::1")
+	// convert IP address in string form into ip_types.Address
+	convertIPAddress("10.10.1.1")
+	convertIPAddress("ff80::1")
 
-	// convert IP from string form into Prefix type
+	// convert IP address / CIDR in string form into ip_types.Prefix
 	convertIPPrefix("20.10.1.1/24")
 	convertIPPrefix("21.10.1.1")
 	convertIPPrefix("ff90::1/64")
 	convertIPPrefix("ff91::1")
 
-	// convert MAC address from string into MacAddress
+	// convert MAC address in string form into ethernet_types.MacAddress
 	convertToMacAddress("00:10:ab:4f:00:01")
+
+	// convert time.Time into vpe_types.Timestamp
+	convertToTimestamp(time.Now())
 }
 
-func addressUnionExample() {
+func usageUnion() {
 	var union ip_types.AddressUnion
 
 	// initialize union using constructors
@@ -63,21 +69,17 @@ func addressUnionExample() {
 	union.SetIP6(ip6)
 }
 
-func ipAddressExample() {
+func usageAddress() {
 	// parse string into IP address
-	addrIP4, err := ip_types.ParseAddress("192.168.1.10")
+	addr, err := ip_types.ParseAddress("192.168.1.10")
 	if err != nil {
 		panic(err)
 	}
-	/*addrIP6, err := ip_types.ParseAddress("ff:2::2")
-	if err != nil {
-		panic(err)
-	}*/
 
 	var msg = ip.IPPuntRedirect{
 		IsAdd: true,
 		Punt: ip.PuntRedirect{
-			Nh: addrIP4,
+			Nh: addr,
 		},
 	}
 
@@ -103,7 +105,7 @@ func ipAddressExample() {
 	}
 }
 
-func convertIP(ip string) {
+func convertIPAddress(ip string) {
 	addr, err := ip_types.ParseAddress(ip)
 	if err != nil {
 		log.Printf("error converting IP to Address: %v", err)
@@ -135,3 +137,10 @@ func convertToMacAddress(mac string) {
 
 	fmt.Printf("MacAddress converted back to string %#v to: %s\n", parsedMac, parsedMac)
 }
+
+func convertToTimestamp(t time.Time) {
+	timestamp := vpe_types.NewTimestamp(t)
+	fmt.Printf("converted time %v to: %#v\n", t, timestamp)
+
+	fmt.Printf("Timestamp converted back to string %#v to: %s\n", timestamp, timestamp)
+}
diff --git a/examples/simple-client/simple_client.go b/examples/simple-client/simple_client.go
index 0898c0a..10a0ea6 100644
--- a/examples/simple-client/simple_client.go
+++ b/examples/simple-client/simple_client.go
@@ -84,6 +84,7 @@ func main() {
 
 	// use request/reply (channel API)
 	getVppVersion(ch)
+	getSystemTime(ch)
 	idx := createLoopback(ch)
 	interfaceDump(ch)
 	addIPAddress(ch, idx)
@@ -107,6 +108,22 @@ func getVppVersion(ch api.Channel) {
 	fmt.Println()
 }
 
+func getSystemTime(ch api.Channel) {
+	fmt.Println("Retrieving system time..")
+
+	req := &vpe.ShowVpeSystemTime{}
+	reply := &vpe.ShowVpeSystemTimeReply{}
+
+	if err := ch.SendRequest(req).ReceiveReply(reply); err != nil {
+		logError(err, "retrieving system time")
+		return
+	}
+
+	fmt.Printf("system time: %v\n", reply.VpeSystemTime)
+	fmt.Println("OK")
+	fmt.Println()
+}
+
 func createLoopback(ch api.Channel) interface_types.InterfaceIndex {
 	fmt.Println("Creating loopback interface..")