Details
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Improvement
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Status: Resolved
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Major
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Resolution: Fixed
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None
Description
The Avro IDL format is not widely adopted, as it yields a protocol (most people use schemas only). To remedy this, I propose to extend the IDL syntax.
Future IDL files will have two options:
- Use the existing syntax to define a protocol
Parsing such a file yields a protocol and a collection of named schemas (that can also be found in the protocol object) - Use the syntax below to define a schema
Parsing such a file yields a collection of named schemas and optionally a "main schema", which can be a named or an anonymous schema.
Proposed syntax:
// Optional: the default namespace for the whole file (defaults to the null namespace if omitted)
// (in the existing syntax, the namespace of the protocol has the same function)
namespace my.name.space;
// Optional: a main schema to parse the file as a .avsc equivalent
schema array<Message>;
// Below here are imports and named schemas in any order
/* Import rules for the new syntax:
- the namespace of the imported named types is determined by the imported file
(same as for the existing syntax)
- when importing idl or protocol files, only the named schemas are imported
(as this syntax supports only these)
*/
import idl "common.avdl";
/**
* A message to communicate.
*/
record Message {
array<Header> headers;
string? title = null; // Idea: add null as default value, unless there's an explicit default value
string message;
timestamp_ms sendTime;
}
