Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Avro >> mail # user >> Schema validation of a field's default values


Copy link to this message
-
Re: Schema validation of a field's default values
On Fri, Oct 19, 2012 at 5:19 PM, Mark Hayes <[EMAIL PROTECTED]> wrote:
> It looks like the Schema parser doesn't check a field's default value
> against the field's type.  So for example, you can define a string default
> value for a field of type int.  Since the default value is only used in
> certain circumstances for schema resolution, such an error might not easily
> be caught during testing, so the danger is that it would crop up at runtime.
>
> Am I correct, so far?

Yes, that's correct.

> If so, does anyone know of facility in the Avro library, or another library,
> for checking the schema to ensure that default values are of the proper
> type?  I wasn't able to find one, so I'm considering implementing one
> myself.

No, I don't know of a default value validator that's been implemented
yet.  It would be great to have one.

I think this would recursively walk a schema.  Whenever a non-null
default value is found it could call ResolvingGrammarDecoder#encode().
 That's what interprets Json default values.  (Perhaps this logic
should be moved, though.)

Doug