Gregory 2013-06-19, 21:34
> I wrote a little C tool using Avro-C to convert JSON to Avro and thought
> may be someone here may find it useful.
> The purpose is to be useful in converting messy legacy JSON in which
> some elements might be missing or of wrong type. Even though there is no
> schema resolution per se here, json2avro will attempt to use the default
> specified in the schema if the corresponding JSON element is missing and
> will attempt to try the types specified in a union until one succeeds.
> json2avro lets you pick from null, snappy, deflate and lzma codecs,
> specify a custom block size and optionally skips over JSON lines that it
> is unable to parse. I'm also thinking of adding a target max file size
> so that it would automatically split output into multiple sizes.
Very cool! Kind of the reverse of avrocat or avropipe. We could clean
it up and add it as another C command-line tool if you like.
> It uses Jansson as the JSON parser which is conveniently bundled with
> Avro-C. (One thing that I'm not clear on is that Jansson cannot handle
> nulls, not sure if this is a Jansson-specific limitation or something
> inherent to JSON.)
Can you elaborate on this? Jansson should support null JSON values
(it's the keyword null, not the string value "null"). And the Avro C
bindings should use that for Avro null values.
Gregory 2013-06-25, 14:48
Douglas Creager 2013-06-25, 15:10