Hi Igniters, I propose new rules and infrastructure around working with Message classes. This work is being doing for IEP-132 Rolling Upgrade [1], [2].
Previously, we had an optional code generator for Message#writeTo, Message#readFrom code. I'm propose a patch [3] which makes the generation mandatory and enforces it at compile time using javax.annotation.processor [4] framework. What's changing: 1. All Message classes must now follow strict rules. - Strict field ordering via @Order annotation. - Naming conventions (field/getter/setter alignment). - Type of fields must not be changed. 2. There are 2 steps for the rules validation: at compile time and during PR checks. 3. Message#readFrom and Message#writeTo methods now are deprecated and will be removed in the future. Instead, a [Message]Serializer class is generated at compile time. Serializers must be registered in GridIoMessageFactory. 4. The ignite-core module now depends on the ignite-codegen2 module. This is required because the framework needs a pre-compiled .jar for generation. 5. The ignite-codegen and ignite-codegen2 modules will be merged later, after we refactor SystemViewRowAttributeWalkerGenerator to use the same framework. For now, cyclic dependencies prevent using a single module for both generators. 6. Binary representation of Message doesn't change. Then we will refactor Message by Message in background. The patch [3] includes an example for GridJobCancelRequest. Please take a look. Thanks Sergey Chugunov for his contribution and efforts in the review. Igniters, please share your thoughts. If no objections, I'll proceeding with merging the patch on Friday, 4th of July. [1] https://cwiki.apache.org/confluence/display/IGNITE/IEP-132+Rolling+Upgrade [2] https://cwiki.apache.org/confluence/display/IGNITE/Communication+protocol [3] https://github.com/apache/ignite/pull/12129 [4] https://docs.oracle.com/en/java/javase/11/docs/api/java.compiler/javax/annotation/processing/package-summary.html
