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Finally, an EventSchemaMapper is provider to map events from new schema (N) to previous schema (N-1) and the other way around. This mapper needs to have some logic depending on the change made in the schema. For example, If new fields are added in the new schema, they might be given a default value in the previous one, if possible.
No more than 2 schemas versions are supported at the same time.
Following is an example of v0 and v1 schema definition in cps-events module.
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