We're indeed using the writer's schema so we're not having the issue but I was curious.
I was referring to schema resolution as pointed out, so I should have RTFM more thoroughly I guess ¯\_(ツ)_/¯ Thank you both for your answers. Le mer. 30 mai 2018 à 16:49, Bridger Howell <bhow...@sofi.org> a écrit : > > Then a reader with the newer schema will consume messages with value 3 > and decoded it as enum value "E". > > If you try to consume the old data treating it as if it were written with > the newer schema, then yes that would cause issues, but that's normally how > avro is used. > > For avro compatibility to work normally, it's expected that the writer's > schema is available when reading the data, removing the sorts of issues you > pointed out. > The transformation of data written with one schema into a different schema > is called schema resolution, and you can read more about it here: > https://avro.apache.org/docs/current/spec.html#Schema+Resolution > > On Wed, May 30, 2018 at 6:35 AM, Arnaud BOS <arnaud.t...@gmail.com> wrote: > >> Quick question: is reordering the values of an enum a backward compatible >> change? >> >> Per the Avro 1.8.2 documentation: "An enum is encoded by a int, >> representing the zero-based position of the symbol in the schema." >> >> If my enum is: >> >> {"type": "enum", "name": "Foo", "symbols": ["A", "B", "C", "D"] } >> >> And I update it to >> >> {"type": "enum", "name": "Foo", "symbols": ["A", "B", "C", "E", "F", "D"] } >> >> >> If a writer with the older schema will produce messages using enum value >> "D" encoded as int 3. >> Then a reader with the newer schema will consume messages with value 3 >> and decoded it as enum value "E". >> >> If this is the case, then reordering enums is just as non-backward >> compatible as adding new values is non-forward compatible, is it correct? >> > > The information contained in this email message is PRIVATE and intended > only for the personal and confidential use of the recipient named above. If > the reader of this message is not the intended recipient or an agent > responsible for delivering it to the intended recipient, you are hereby > notified that you have received this message in error and that any review, > dissemination, distribution or copying of this message is strictly > prohibited. If you have received this communication in error, please > notify us immediately by email, and delete the original message. >
