FIXTradingCommunity / fix-simple-binary-encoding

A FIX standard for binary message encoding
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RC4 documentation doesn't match xsd, type/@characterEncoding #72

Closed bkc closed 6 years ago

bkc commented 6 years ago

encodedDataType in this xsd https://github.com/FIXTradingCommunity/fix-simple-binary-encoding/blob/master/v1-0-RC4/resources/SimpleBinary1-0.xsd lists characterEncoding as an optional attribute

But characterEncoding is not mentioned in the documentation for Type in https://github.com/FIXTradingCommunity/fix-simple-binary-encoding/blob/master/v1-0-RC4/doc/04MessageSchema.md#type-element-content

donmendelson commented 6 years ago

First, note that version RC4 was promoted to technical standard version 1.0, so folder v1-0-STANDARD supersedes it. (All versions are retained for an historical record.) Version 1.0 is now immutable but version 2.0 RC1 is open for further enhancements.

That said, you are correct that attribute characterEncoding is missing from the table in section 4. It is shown in an example in section 2 under the heading "Encoding specifications for variable-length string".

The specification also says that single-byte character fields are encoded with US-ASCII. (This makes character codes compatible with FIX tag value encoding.)

Field length in SBE is in octets, not characters. This makes it impractical for fixed-length character fields of Unicode encodings since the number of octets is not a fixed relationship with number of glyphs. This leaves variable-length fields conducive to other encodings.

Are you suggesting an enhancement or just reporting an omission in the spec?

bkc commented 6 years ago

Hi,

Sorry I was just pointing out an omission. Thanks also for reminding me to pay attention to versioning. I am trying to use another project that refers to rc3 spec. In my haste my brain said "ah, rc4 looks newer, I should support that just in case they move from rc3 to rc4".. I completely glossed over that rc = release candidate and that what I really want is to support '1.0'

thanks for the wakeup.. closing issue