Release v0.10.0

Changelog

• added message.Marshal(data) which sets values of message fields using values provided in the data struct.
• added support of index tag for both message.Marshal() and message.Unmarshal(). Now you can name your fields as you want and use index tag to specify the field index matching the ISO8583 specification. Examples are here and here.
• removed iso8583.Unmarshal. Please, use message.Unmarshal instead.
• removed message.Data()
• deprecated message.SetData(data). Use message.Marshal() instead.
• deprecated field.SetData(data). Use field.Marshal(data) instead.
• changed current behavior of message.SetData(data). Before it could be used to get values into a struct after calling message.Unpack() like this:

data := &ISOMessage{}
mesage.SetData(data)
message.Unpack(rawMessage)

data.F1.Value //  in previous versions, values were populated during unpacking, but now they are not

Now message.SetData(data) only sets field values and you can't get values back to the struct using it. In order to get values into the struct you have to use message.Unmarshal(data) like this:

message.Unpack(rawMessage)
data := &ISOMessage{}
mesage.Unmarshall(data)

data.F1.Value //  now you can get the value

Migration Guide

Two main changes that you may need to do in your code:

1. Replace message.SetData(data) with message.Marshal(data). Latter simply sets field values with values provided in the data struct. Without any side effects.
2. Replace message.Data()(*YouMessageTypehere) with message.Unmarshal(data). It sets data struct values with message field values. No side-effects.
3. If you used SetData() with Unpack to get access to message field values, then you have to replace it with just message.Unmarshal(data).

You have to change your code from this

type ISO87Data struct {
	F0 *field.String
	F2 *field.String
	F4 *field.String
}

message := NewMessage(spec)
data := &ISO87Data{}
err := message.SetData(data) // you "link" data internally
err = message.Unpack(rawMsg) // here values are populated into linked data struct. it will not work anymore.

// access field values
data.F0.Value
data.F2.Value
data.F4.Value

to this:

type ISO87Data struct {
	F0 *field.String
	F2 *field.String
	F4 *field.String
}

message := NewMessage(spec)
err := message.Unpack(rawMsg)

data := &ISO87Data{}
err = message.Unmarshal(data)

// access field values
data.F0.Value
data.F2.Value
data.F4.Value

If you have any questions, please, submit an issue or ask in our community Slack channel.