Add Support for logical duration type

[hsn10]

I need support for logical type duration.

 "fields": [
    {"name":"start","type" : {"type":"long", "logicalType":"timestamp-millis"}},
    {"name":"duration","type" : {"type":"fixed","size":12, "logicalType":"duration","name":"duration"}},

I see ticked that fixed type is not yet implemented. Can be duration type implemented without implementing fixed type first?

[julianpeeters]

I think so @hsn10. Some parts of the code path for fixed would need to be implemented, for example, in the TypeMatcher, but I don't think we'd need full support for fixed (although I'm not entirely sure).

[hsn10]

It is probably too early. I studied avro codebase and there is no converter for timestamp-micros and duration logical types. This means that schema to java generator will produce incorrect result and there is no point in implementing scala interface.

Because correct definition of duration type field is:

{"name":"duration","type" : {"type":"fixed","size":12, "logicalType":"duration"}},

which does not compile to Java files, compilator complains about missing name. If name is use then this statement is compiled into sub type.

[julianpeeters]

thanks for reporting your findings 👍