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https://issues.apache.org/jira/browse/AVRO-3370?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Ryan Skraba resolved AVRO-3370.
-------------------------------
Resolution: Fixed
> [Spec] Inconsistent behaviour on types as invalid names.
> --------------------------------------------------------
>
> Key: AVRO-3370
> URL: https://issues.apache.org/jira/browse/AVRO-3370
> Project: Apache Avro
> Issue Type: Bug
> Reporter: Ryan Skraba
> Assignee: Ryan Skraba
> Priority: Major
> Labels: pull-request-available
> Fix For: 1.11.1
>
> Time Spent: 2.5h
> Remaining Estimate: 0h
>
> We've run across this in some code that interoperates between Java and Python.
> The spec [currently
> forbids|https://avro.apache.org/docs/current/spec.html#names] using a
> primitive type name as a keyword: _*Primitive type names have no namespace
> and their names may not be defined in any namespace.*_
> {code:java}
> {"type":"record","name":"long","fields":[{"name":"a1","type":"long"}]} {code}
> That fails in Java with {{"org.apache.avro.AvroTypeException: Schemas may not
> be named after primitives: long"}}
> What do we expect to happen when a named schema uses a complex type?
> {code:java}
> {"type":"record","name":"record","fields":[{"name":"a1","type":"long"}]}
> {code}
> This currently *succeeds* in Java and the schema can be used to serialize and
> deserialize data.
> This currently *fails* in Python with: {{avro.schema.SchemaParseException:
> record is a reserved type name}}
> Which one is the correct behaviour?
> This gets a bit more complicated when we consider using the name as a
> reference.
> The following two schemas both work in Java:
> {code:java}
> {"type":"record","name":"LinkedList",
> "fields":[
> {"name":"value","type":"int},
> {"name":"next","type":["null","LinkedList"]}]}" {code}
> {code:java}
> {"type":"record","name":"LinkedList",
> "fields":[
> {"name":"value","type":"int},
> {"name":"next","type":["null",{"type":"LinkedList"}]}]}"
> {code}
> If we rename {{LinkedList}} to {{record}} the former succeeds in Java and the
> latter fails with {{{}org.apache.avro.SchemaParseException: No name in
> schema: {"type":"record"{}}}}
> {*}Edit{*}: The consensus on the [mailing
> list|https://lists.apache.org/thread/0wmgyx6z69gy07lvj9ndko75752b8cn2] is the
> "permissive" behaviour of Java should be adopted, in order to align the SDKs.
> The specification doesn't currently forbid these, and this should be
> clarified explicitly. We should probably say that it's a best practice to
> avoid doing this, especially in the null namespace, since it can be confusing
> to a reader and potentially cause ambiguities when JSON encoding data.
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