Proposal to expose PgClient functionality through R2DBC API

R2DBC is an initiative to establish a common SPI for relational database drivers embracing reactive programming properties: Event-oriented, non-blocking, and ideally stream-oriented access to databases. R2DBC is built entirely on Reactive Streams defining a minimal API surface to be implemented by drivers without the need to re-implement common client functionality in every driver.

From an R2DBC perspective there are a couple of interfaces that could be implemented by using the following components of PgClient:

• ConnectionFactory -> PgClient and PgPool
• Connection -> PgConnection
• Statement -> Utility to build/prepare a statement, eventually calling PgConnection.query(…) or PgConnection.preparedQuery(…) methods
• Result -> PgRowSet
• Row -> (Pg) Row

What is the benefit of doing so?

Benefits:

• Following an API that is well-suited for client developers without the need to entirely change how the client is supposed to work
• Participating in a growing client-ecosystem (MyBatis, draft, JDBI, Spring) with clients providing a humane API. Application developers get a choice of which client they want to use for specific use-cases.
• With the choice of clients, PgClient isn’t required to provide additional functionality such as object mapping or SQL generation. That’s up to the client.
• Choice of plug and play for a growing eco-system of drivers beyond Postgres and MySQL (e.g. H2, Microsoft SQL Server) that can be used with vert.x.

Drawbacks:

• https://xkcd.com/927/
• Dependency on Reactive Streams (could be optional, still)
• Additional complexity by maintaining two driver frontends

Related ticket: #245.

[mp911de]

@vietj did you had a chance to have look at https://gist.github.com/mp911de/9ea13939e8fd9a6b4ef138419f085715 outlining the intended PR? If so, I could start working on a pull request. WDYT?

[lukaseder]

Another set of potential users of this integration (all via jOOQ):

• https://stackoverflow.com/q/72669626/521799
• https://github.com/quarkiverse/quarkus-jooq/issues/38
• https://github.com/jklingsporn/vertx-jooq/issues/205

While it seems that Red Hat isn’t interested in moving forward with this (@vietj, why? Any background you can share on this decision? What would be needed to revert it?)

Is there any reason why @mp911de’s work couldn’t be published as one of these projects? https://r2dbc.io/drivers