Convert PutDate/Time between MQI strings and Go time.Time (inspired by #159)

Author: ibmmqmet

ibmmq/mqi.go

@@ -22,7 +22,7 @@ directories.
 package ibmmq
 
 /*
-  Copyright (c) IBM Corporation 2016, 2019
+  Copyright (c) IBM Corporation 2016, 2021
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
@@ -59,9 +59,11 @@ import "C"
 
 import (
 	"encoding/binary"
+	_ "fmt"
 	"io"
 	"os"
 	"strings"
+	"time"
 	"unsafe"
 )
 
@@ -126,7 +128,11 @@ func (e *MQReturn) Error() string {
 
 var endian binary.ByteOrder // Used by structure formatters such as MQCFH
 const space8 = "        "
-
+const (
+  mqDateTimeFormat = "20060102150405.00 MST" // Used as the way to parse a string into a time.Time type with magic values
+  mqDateFormat     = "20060102"
+	mqTimeFormat     = "150405.00"
+)
 // This function is executed once before any other code in the package
 func init() {
 	if C.MQENC_NATIVE%2 == 0 {
@@ -1383,3 +1389,32 @@ func readStringFromFixedBuffer(r io.Reader, l int32) string {
 	binary.Read(r, endian, tmpBuf)
 	return strings.TrimSpace(string(tmpBuf))
 }
+
+
+// The date/time fields are being taken from a valid MQMD but they still might not be
+// "real" timestamps if the putting application has overridden context setting. If the values
+// are invalid, then we return an empty Go value
+func createGoDateTime(d string,t string) time.Time {
+
+	if len(d) == int(MQ_PUT_DATE_LENGTH) && len(t) == int(MQ_PUT_TIME_LENGTH) {
+		// Combine the MQI strings into a single parseable string
+		s := d + t[:6] + "." + t[6:] + " UTC" // MQ times are always given as UTC
+		goTime, err := time.Parse(mqDateTimeFormat, s)
+		if err != nil {
+			return time.Time{}
+		} else {
+			return goTime
+		}
+	} else {
+    return time.Time{}
+  }
+}
+
+// If the application has set a Go timestamp, it ought to be valid. So we can try to convert it
+// to the MQ separate string formats.
+func createCDateTime(goTime time.Time) (string,string) {
+	d:= goTime.Format(mqDateFormat) // These magic values tell Go how to parse/format between Times and strings
+	t:= goTime.Format(mqTimeFormat)
+	t = t[:6] + t[7:] // Strip the '.'
+	return d,t
+}

ibmmq/mqiDLH.go

@@ -1,7 +1,7 @@
 package ibmmq
 
 /*
-  Copyright (c) IBM Corporation 2016,2018
+  Copyright (c) IBM Corporation 2016,2021
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
@@ -29,6 +29,7 @@ import "C"
 import (
 	"bytes"
 	"encoding/binary"
+	"time"
 )
 
 type MQDLH struct {
@@ -40,8 +41,9 @@ type MQDLH struct {
 	Format         string
 	PutApplType    int32
 	PutApplName    string
-	PutDate        string
-	PutTime        string
+	PutDate        string // Deprecated
+	PutTime        string // Deprecated
+	PutDateTime    time.Time // Combines the PutDate and PutTime fields - takes precedence if both styles are used
 	strucLength    int // Not exported
 }
 
@@ -107,6 +109,10 @@ func (dlh *MQDLH) Bytes() []byte {
 	offset += 4
 	copy(buf[offset:], dlh.PutApplName)
 	offset += int(MQ_PUT_APPL_NAME_LENGTH)
+
+	if !dlh.PutDateTime.IsZero() {
+		dlh.PutDate,dlh.PutTime = createCDateTime(dlh.PutDateTime)
+	}
 	copy(buf[offset:], dlh.PutDate)
 	offset += int(MQ_PUT_DATE_LENGTH)
 	copy(buf[offset:], dlh.PutTime)
@@ -144,6 +150,7 @@ func getHeaderDLH(md *MQMD, buf []byte) (*MQDLH, int, error) {
 	dlh.PutApplName = readStringFromFixedBuffer(r, MQ_PUT_APPL_NAME_LENGTH)
 	dlh.PutDate = readStringFromFixedBuffer(r, MQ_PUT_DATE_LENGTH)
 	dlh.PutTime = readStringFromFixedBuffer(r, MQ_PUT_TIME_LENGTH)
+	dlh.PutDateTime = createGoDateTime(dlh.PutDate,dlh.PutTime)
 
 	return dlh, dlh.strucLength, nil
 }

ibmmq/mqiMQMD.go

@@ -1,7 +1,7 @@
 package ibmmq
 
 /*
-  Copyright (c) IBM Corporation 2016
+  Copyright (c) IBM Corporation 2016, 2021
 
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
@@ -30,6 +30,7 @@ import "C"
 
 import (
 	"bytes"
+	"time"
 )
 
 /*
@@ -56,8 +57,9 @@ type MQMD struct {
 	ApplIdentityData string
 	PutApplType      int32
 	PutApplName      string
-	PutDate          string
-	PutTime          string
+	PutDate          string // Deprecated
+	PutTime          string // Deprecated
+	PutDateTime      time.Time // Combines the PutDate and PutTime fields - takes precedence if both styles are used
 	ApplOriginData   string
 	GroupId          []byte
 	MsgSeqNumber     int32
@@ -119,6 +121,13 @@ func checkMD(gomd *MQMD, verb string) error {
 		mqrc = C.MQRC_MD_ERROR // No specific error defined
 	}
 
+	if len(gomd.PutDate) != 0 && len(gomd.PutDate) != C.MQ_PUT_DATE_LENGTH {
+		mqrc = C.MQRC_MD_ERROR
+	}
+	if len(gomd.PutTime) != 0 && len(gomd.PutTime) != C.MQ_PUT_TIME_LENGTH {
+		mqrc = C.MQRC_MD_ERROR
+	}
+
 	if mqrc != C.MQRC_NONE {
 		mqreturn := MQReturn{MQCC: C.MQCC_FAILED,
 			MQRC: int32(mqrc),
@@ -162,6 +171,9 @@ func copyMDtoC(mqmd *C.MQMD, gomd *MQMD) {
 	setMQIString((*C.char)(&mqmd.ApplIdentityData[0]), gomd.ApplIdentityData, C.MQ_APPL_IDENTITY_DATA_LENGTH)
 	mqmd.PutApplType = C.MQLONG(gomd.PutApplType)
 	setMQIString((*C.char)(&mqmd.PutApplName[0]), gomd.PutApplName, C.MQ_PUT_APPL_NAME_LENGTH)
+	if !gomd.PutDateTime.IsZero() {
+		gomd.PutDate,gomd.PutTime = createCDateTime(gomd.PutDateTime)
+	}
 	setMQIString((*C.char)(&mqmd.PutDate[0]), gomd.PutDate, C.MQ_PUT_DATE_LENGTH)
 	setMQIString((*C.char)(&mqmd.PutTime[0]), gomd.PutTime, C.MQ_PUT_TIME_LENGTH)
 	setMQIString((*C.char)(&mqmd.ApplOriginData[0]), gomd.ApplOriginData, C.MQ_APPL_ORIGIN_DATA_LENGTH)
@@ -210,6 +222,7 @@ func copyMDfromC(mqmd *C.MQMD, gomd *MQMD) {
 	gomd.PutApplName = trimStringN((*C.char)(&mqmd.PutApplName[0]), C.MQ_PUT_APPL_NAME_LENGTH)
 	gomd.PutDate = trimStringN((*C.char)(&mqmd.PutDate[0]), C.MQ_PUT_DATE_LENGTH)
 	gomd.PutTime = trimStringN((*C.char)(&mqmd.PutTime[0]), C.MQ_PUT_TIME_LENGTH)
+	gomd.PutDateTime = createGoDateTime(gomd.PutDate,gomd.PutTime)
 	gomd.ApplOriginData = trimStringN((*C.char)(&mqmd.ApplOriginData[0]), C.MQ_APPL_ORIGIN_DATA_LENGTH)
 
 	for i = 0; i < C.MQ_GROUP_ID_LENGTH; i++ {