MLText XML binding

ffm message

In the last FFM TC call it was noted that the XML binding of the MLText type (as it was presented in the latest schema) did not quite conform to the general WSDL binding convention used for the other types. As I started to fix this I realized the original reason why it had been implemented this way.

MLText type is used in many places over the spec to hold text that may be localized for several different target locales. Because the MLText type is used in many places and it only contains very simple information (either a single string or a set of alternative localized strings) it would be nice if it also had a simple and efficient XML serialized form. This is the reason why MLText currently has a custom XML binding, slightly deviating from the general WSDL binding convention used for the other types.

The following is an example of how a single localized text field, such as the display label of an Action or a Data Element, would be serialized using the current MLText XML binding:

...

<ffmcm:Label>

<ffmcm:Value>Start</ffmcm:Value>

<ffmcm:Value Locale="sv">Starta</ffmcm:Value>

<ffmcm:Value Locale="fi">Aloita</ffmcm:Value>

</ffmcm:Label>

...

The following example shows the same data serialized using the general WSDL binding convention for MLText.

...

<ffmcm:Label>

<ffmcm:Values>

<ffmcm:LocalizedString>

<ffmcm:Value>Start</ffmcm:Value>

</ffmcm:LocalizedString>

<ffmcm:LocalizedString>

<ffmcm:Locale>sv</ffmcm:Locale>

<ffmcm:Value>Starta</ffmcm:Value>

</ffmcm:LocalizedString>

<ffmcm:LocalizedString>

<ffmcm:Locale>fi</ffmcm:Locale>

<ffmcm:Value>Aloita</ffmcm:Value>

</ffmcm:LocalizedString>

</ffmcm:Values>

</ffmcm:Label>

...

As you can see, the latter version is both harder to read for a human and it is also much less efficient in terms of how much markup is needed to carry the same amount of actual payload data.

Therefore, I propose that we keep the current XML binding for MLText but describe this deviation from the general binding conventions in the binding part of the spec. I will submit the additional description as further input.