Add iso8601 support

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/gorilla/websocket v1.4.1
 	github.com/kr/pretty v0.1.0 // indirect
 	github.com/leodido/go-urn v1.1.0 // indirect
+	github.com/relvacode/iso8601 v1.3.0 // indirect
 	github.com/sirupsen/logrus v1.4.2
 	github.com/stretchr/testify v1.8.0
 	golang.org/x/sys v0.0.0-20220804214406-8e32c043e418 // indirect

go.sum

@@ -22,6 +22,8 @@ github.com/leodido/go-urn v1.1.0 h1:Sm1gr51B1kKyfD2BlRcLSiEkffoG96g6TPv6eRoEiB8=
 github.com/leodido/go-urn v1.1.0/go.mod h1:+cyI34gQWZcE1eQU7NVgKkkzdXDQHr1dBMtdAPozLkw=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/relvacode/iso8601 v1.3.0 h1:HguUjsGpIMh/zsTczGN3DVJFxTU/GX+MMmzcKoMO7ko=
+github.com/relvacode/iso8601 v1.3.0/go.mod h1:FlNp+jz+TXpyRqgmM7tnzHHzBnz776kmAH2h3sZCn0I=
 github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
 github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

ocpp1.6/types/datetime.go

@@ -2,14 +2,13 @@ package types
 
 import (
 	"encoding/json"
-	"strings"
+	"errors"
 	"time"
-)
 
-// ISO8601 time format, assuming Zulu timestamp.
-const ISO8601 = "2006-01-02T15:04:05Z"
+	"github.com/relvacode/iso8601"
+)
 
-// DateTimeFormat to be used for all OCPP messages.
+// DateTimeFormat to be used when serializing all OCPP messages.
 //
 // The default dateTime format is RFC3339.
 // Change this if another format is desired.
@@ -25,24 +24,31 @@ func NewDateTime(time time.Time) *DateTime {
 	return &DateTime{Time: time}
 }
 
+func null(b []byte) bool {
+	if len(b) != 4 {
+		return false
+	}
+	if b[0] != 'n' && b[1] != 'u' && b[2] != 'l' && b[3] != 'l' {
+		return false
+	}
+	return true
+}
+
 func (dt *DateTime) UnmarshalJSON(input []byte) error {
-	strInput := string(input)
-	strInput = strings.Trim(strInput, `"`)
-	if DateTimeFormat == "" {
-		var defaultTime time.Time
-		err := json.Unmarshal(input, &defaultTime)
-		if err != nil {
-			return err
-		}
-		dt.Time = defaultTime.Local()
+	// Do not parse null timestamps
+	if null(input) {
+		return nil
+	}
+	// Assert that timestamp is a string
+	if len(input) > 0 && input[0] == '"' && input[len(input)-1] == '"' {
+		input = input[1 : len(input)-1]
 	} else {
-		newTime, err := time.Parse(DateTimeFormat, strInput)
-		if err != nil {
-			return err
-		}
-		dt.Time = newTime.Local()
+		return errors.New("timestamp not enclosed in double quotes")
 	}
-	return nil
+	// Parse ISO8601
+	var err error
+	dt.Time, err = iso8601.Parse(input)
+	return err
 }
 
 func (dt *DateTime) MarshalJSON() ([]byte, error) {

ocpp1.6_test/common_test.go

@@ -1,8 +1,13 @@
 package ocpp16_test
 
 import (
-	"github.com/lorenzodonini/ocpp-go/ocpp1.6/types"
+	"encoding/json"
+	"strings"
 	"time"
+
+	"github.com/relvacode/iso8601"
+
+	"github.com/lorenzodonini/ocpp-go/ocpp1.6/types"
 )
 
 // Utility functions
@@ -114,3 +119,60 @@ func (suite *OcppV16TestSuite) TestMeterValueValidation() {
 	}
 	ExecuteGenericTestTable(suite.T(), testTable)
 }
+
+func (suite *OcppV16TestSuite) TestUnmarshalDateTime() {
+	testTable := []struct {
+		RawDateTime   string
+		ExpectedValid bool
+		ExpectedTime  time.Time
+		ExpectedError error
+	}{
+		{"\"2019-03-01T10:00:00Z\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00+01:00\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000Z\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000+01:00\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00+01\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000+01\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01 10:00:00+00:00\"", false, time.Time{}, &iso8601.UnexpectedCharacterError{Character: ' '}},
+		{"\"null\"", false, time.Time{}, &iso8601.UnexpectedCharacterError{Character: 110}},
+		{"\"\"", false, time.Time{}, &iso8601.RangeError{Element: "month", Min: 1, Max: 12}},
+		{"null", true, time.Time{}, nil},
+	}
+	for _, dt := range testTable {
+		jsonStr := []byte(dt.RawDateTime)
+		var dateTime types.DateTime
+		err := json.Unmarshal(jsonStr, &dateTime)
+		if dt.ExpectedValid {
+			suite.NoError(err)
+			suite.NotNil(dateTime)
+			suite.True(dt.ExpectedTime.Equal(dateTime.Time))
+		} else {
+			suite.Error(err)
+			suite.ErrorAs(err, &dt.ExpectedError)
+		}
+	}
+}
+
+func (suite *OcppV16TestSuite) TestMarshalDateTime() {
+	testTable := []struct {
+		Time                    time.Time
+		Format                  string
+		ExpectedFormattedString string
+	}{
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), "", "2019-03-01T10:00:00Z"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC3339, "2019-03-01T10:00:00Z"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC822, "01 Mar 19 10:00 UTC"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC1123, "Fri, 01 Mar 2019 10:00:00 UTC"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), "invalidFormat", "invalidFormat"},
+	}
+	for _, dt := range testTable {
+		dateTime := types.NewDateTime(dt.Time)
+		types.DateTimeFormat = dt.Format
+		rawJson, err := dateTime.MarshalJSON()
+		suite.NoError(err)
+		formatted := strings.Trim(string(rawJson), "\"")
+		suite.Equal(dt.ExpectedFormattedString, formatted)
+	}
+}

ocpp1.6_test/ocpp16_test.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"reflect"
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/require"
 
@@ -708,6 +709,7 @@ func (suite *OcppV16TestSuite) SetupTest() {
 		return defaultMessageId
 	}}
 	ocppj.SetMessageIdGenerator(suite.messageIdGenerator.generateId)
+	types.DateTimeFormat = time.RFC3339
 }
 
 func (suite *OcppV16TestSuite) TestIsConnected() {

ocpp2.0.1/types/datetime.go

@@ -2,11 +2,13 @@ package types
 
 import (
 	"encoding/json"
-	"strings"
+	"errors"
 	"time"
+
+	"github.com/relvacode/iso8601"
 )
 
-// DateTimeFormat to be used for all OCPP messages.
+// DateTimeFormat to be used when serializing all OCPP messages.
 //
 // The default dateTime format is RFC3339.
 // Change this if another format is desired.
@@ -22,36 +24,38 @@ func NewDateTime(time time.Time) *DateTime {
 	return &DateTime{Time: time}
 }
 
-// Creates a new DateTime struct, embedding a struct generated using time.Now().
-func Now() *DateTime {
-	return &DateTime{Time: time.Now()}
+func null(b []byte) bool {
+	if len(b) != 4 {
+		return false
+	}
+	if b[0] != 'n' && b[1] != 'u' && b[2] != 'l' && b[3] != 'l' {
+		return false
+	}
+	return true
 }
 
 func (dt *DateTime) UnmarshalJSON(input []byte) error {
-	strInput := string(input)
-	strInput = strings.Trim(strInput, `"`)
-	if DateTimeFormat == "" {
-		var defaultTime time.Time
-		err := json.Unmarshal(input, &defaultTime)
-		if err != nil {
-			return err
-		}
-		dt.Time = defaultTime.Local()
+	// Do not parse null timestamps
+	if null(input) {
+		return nil
+	}
+	// Assert that timestamp is a string
+	if len(input) > 0 && input[0] == '"' && input[len(input)-1] == '"' {
+		input = input[1 : len(input)-1]
 	} else {
-		newTime, err := time.Parse(DateTimeFormat, strInput)
-		if err != nil {
-			return err
-		}
-		dt.Time = newTime.Local()
+		return errors.New("timestamp not enclosed in double quotes")
 	}
-	return nil
+	// Parse ISO8601
+	var err error
+	dt.Time, err = iso8601.Parse(input)
+	return err
 }
 
 func (dt *DateTime) MarshalJSON() ([]byte, error) {
 	if DateTimeFormat == "" {
 		return json.Marshal(dt.Time)
 	}
-	timeStr := FormatTimestamp(dt.Time)
+	timeStr := dt.FormatTimestamp()
 	return json.Marshal(timeStr)
 }
 

ocpp2.0.1_test/common_test.go

@@ -1,9 +1,12 @@
 package ocpp2_test
 
 import (
+	"encoding/json"
 	"strings"
 	"time"
 
+	"github.com/relvacode/iso8601"
+
 	"github.com/lorenzodonini/ocpp-go/ocpp2.0.1/display"
 	"github.com/lorenzodonini/ocpp-go/ocpp2.0.1/types"
 )
@@ -278,3 +281,60 @@ func (suite *OcppV2TestSuite) TestMessageInfoValidation() {
 	}
 	ExecuteGenericTestTable(suite.T(), testTable)
 }
+
+func (suite *OcppV2TestSuite) TestUnmarshalDateTime() {
+	testTable := []struct {
+		RawDateTime   string
+		ExpectedValid bool
+		ExpectedTime  time.Time
+		ExpectedError error
+	}{
+		{"\"2019-03-01T10:00:00Z\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00+01:00\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000Z\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000+01:00\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00+01\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000\"", true, time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01T10:00:00.000+01\"", true, time.Date(2019, 3, 1, 9, 0, 0, 0, time.UTC), nil},
+		{"\"2019-03-01 10:00:00+00:00\"", false, time.Time{}, &iso8601.UnexpectedCharacterError{Character: ' '}},
+		{"\"null\"", false, time.Time{}, &iso8601.UnexpectedCharacterError{Character: 110}},
+		{"\"\"", false, time.Time{}, &iso8601.RangeError{Element: "month", Min: 1, Max: 12}},
+		{"null", true, time.Time{}, nil},
+	}
+	for _, dt := range testTable {
+		jsonStr := []byte(dt.RawDateTime)
+		var dateTime types.DateTime
+		err := json.Unmarshal(jsonStr, &dateTime)
+		if dt.ExpectedValid {
+			suite.NoError(err)
+			suite.NotNil(dateTime)
+			suite.True(dt.ExpectedTime.Equal(dateTime.Time))
+		} else {
+			suite.Error(err)
+			suite.ErrorAs(err, &dt.ExpectedError)
+		}
+	}
+}
+
+func (suite *OcppV2TestSuite) TestMarshalDateTime() {
+	testTable := []struct {
+		Time                    time.Time
+		Format                  string
+		ExpectedFormattedString string
+	}{
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), "", "2019-03-01T10:00:00Z"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC3339, "2019-03-01T10:00:00Z"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC822, "01 Mar 19 10:00 UTC"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), time.RFC1123, "Fri, 01 Mar 2019 10:00:00 UTC"},
+		{time.Date(2019, 3, 1, 10, 0, 0, 0, time.UTC), "invalidFormat", "invalidFormat"},
+	}
+	for _, dt := range testTable {
+		dateTime := types.NewDateTime(dt.Time)
+		types.DateTimeFormat = dt.Format
+		rawJson, err := dateTime.MarshalJSON()
+		suite.NoError(err)
+		formatted := strings.Trim(string(rawJson), "\"")
+		suite.Equal(dt.ExpectedFormattedString, formatted)
+	}
+}

ocpp2.0.1_test/ocpp2_test.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"reflect"
 	"testing"
+	"time"
 
 	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
@@ -1141,6 +1142,7 @@ func (suite *OcppV2TestSuite) SetupTest() {
 		return defaultMessageId
 	}}
 	ocppj.SetMessageIdGenerator(suite.messageIdGenerator.generateId)
+	types.DateTimeFormat = time.RFC3339
 }
 
 func (suite *OcppV2TestSuite) TestIsConnected() {