Looking at unified FixRepository.xml, I notice that in FIX 4.4 MDEntryType is missing many enumerations, e.g. J (Empty Book). Compare that to fiximate.fixtrading.org. At the same time, if I look into FIX 5.0 (also in FixRepository.xml), the definition of MDEntryType does contain all the missing enumerations and all of them are in fact marked with added="FIX.4.4". Is this a bug in FixRepository.xml or am I missing something? Thanks.
MDEntryType(269)=J (Empty Book) was added with Extension Pack EP7. The process of EPs was started AFTER FIX 4.4 but only as of EP98, each EP was immediately published. Before that, EPs were rolled into the next version of FIX, in the case of EP7 that was FIX 5.0.
Sorry, not really understanding the answer. I’m not sure what EPs are, perhaps some upgrades/revisions. The counterparty runs on FIX 4.4 and they expect J to be in the protocol. Since the XML itself already indicates that it was added="FIX.4.4" but somehow in FIX 5.0 section, is it valid to monkey-patch that XML and backfill these missing constants into FIX 4.4 section? Thanks.
The counterparty cannot expect “J” to be supported because it was not supported with FIX 4.4 when that version was released. Extension Packs extend the capabilities of a base version and are an integral part of the next version. The correct pedigree is not
added=“FIX.4.4”
but
added=“FIX.4.4” addedEP=“7”.
Extension Packs are a mandatory part of the version information, you cannot omit that.