Reactive PostgreSQL client: ability to pin all operations to primary (master) when multiple URLs are configured

[g1phy]

Hello Quarkus team 👋

This issue is related to the following discussion:
#50968

Context

We run production workloads built on Quarkus and are planning to use the reactive PostgreSQL client (quarkus-reactive-pg-client) in a high-availability PostgreSQL setup.

Our database topology follows the classic primary (master) + replicas model, where:

• The primary node handles all writes
• Replicas are used for read scaling / failover
• The master–replica principle is the foundation of our availability strategy

What we want to achieve

We want to configure multiple PostgreSQL URLs (3 endpoints), but have Quarkus:

• Select exactly one primary (master) node
• Route all queries (reads and writes) exclusively to that primary
• Avoid any accidental routing to replicas
• Rely on this setup for full availability and predictable consistency

In other words, we are not looking for read/write splitting at the client level — we want explicit master pinning, even when several URLs are provided.

Questions

1. Is this currently possible with the Quarkus reactive PostgreSQL client?

   • For example:

     • via configuration
     • via a custom pool / resolver
     • via integration with PostgreSQL parameters (target_server_type=primary, etc.)

2. If yes:

   • Could you please describe the recommended configuration or approach?
   • Ideally with an example of how Quarkus determines and sticks to the primary.

3. If no:

   • Are there plans or a roadmap to support this use case?
   • If so, what is the expected direction or timeline?

Why this matters

For many production systems, master-only routing is not an edge case but a baseline requirement for correctness and availability. Having this capability directly in the reactive client would greatly simplify HA deployments and reduce the need for external routing layers.

Thanks a lot for your work on Quarkus and for any clarification you can provide 🙏

[quarkus-bot[bot]]

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