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What's changed and what's your intention?

In our current code, we have many codes that define the whole method in macro to leverage the ability of list expansion inside macro to enumerate over all sources in a match statement, which is hard to read and debug, and the IDE has problem doing indexing on the code in the macro. Besides, when we want to support a new source, we need to add the new source to the list of both properties and split (before the previous refactor we even need to add to the list of reader and enumerator), which is somehow verbose.

In this PR, all sources are declared in a single macro for_all_classified_sources with the following definition.

macro_rules! for_all_classified_sources {
    ($macro:path $(,$extra_args:tt)*) => {
        $macro! {
            // cdc sources
            {
                { Mysql },
                { Postgres },
                { Citus }
            },
            // other sources
            {
                { Kafka, $crate::source::kafka::KafkaProperties, $crate::source::kafka::KafkaSplit },
                { Pulsar, $crate::source::pulsar::PulsarProperties, $crate::source::pulsar::PulsarSplit },
                { Kinesis, $crate::source::kinesis::KinesisProperties, $crate::source::kinesis::split::KinesisSplit },
                { Nexmark, $crate::source::nexmark::NexmarkProperties, $crate::source::nexmark::NexmarkSplit },
                { Datagen, $crate::source::datagen::DatagenProperties, $crate::source::datagen::DatagenSplit },
                { GooglePubsub, $crate::source::google_pubsub::PubsubProperties, $crate::source::google_pubsub::PubsubSplit },
                { Nats, $crate::source::nats::NatsProperties, $crate::source::nats::split::NatsSplit },
                { S3, $crate::source::filesystem::S3Properties, $crate::source::filesystem::FsSplit }
            }
            $(
                ,$extra_args
            )*
        }
    };
}

Based on for_all_classified_sources, we reimplement the current dispatch_source_prop macro for enumerating ConnectorProperties enum, and implement dispatch_split_impl macro for enumerating SplitImpl. With these macros, many methods of ConnectorProperties and SplitImpl previously defined in macro can be implemented in the same way as normal methods. When we want to support a new source, we only need to add its information in the for_all_classified_sources macro.

The end of a series of source refactor. PRs before:

• refactor(source): implement the common split reader as a generic function #12059
• refactor(source): specify cdc generic type parameter for different cdc source #12109
• refactor(source): bind prop, split, reader, enumerator via trait #12184

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.