Pub/Sub Best Practices: Subscribing

Chloe, whose affiliation is not established by the source, presents six subscriber practices covering resource creation, delivery type, acknowledgement, ordering, streaming pull, and flow control.

Key points

• Create durable delivery state before publishing: The episode says to attach a subscription or enable topic retention before messages that must remain available are published ([00:00:00]-[00:01:04]).
• Delivery type is an explicit choice: It lists pull, push, and BigQuery subscriptions as the available 2023 types rather than treating that list as permanently exhaustive ([00:00:00]-[00:01:04]).
• Process before acknowledging: Once acknowledged, a message is not redelivered for incomplete work; repeated handling must still be safe ([00:01:04]-[00:02:09]).
• Ordered redelivery can repeat later messages: If one message is redelivered, subsequent messages for the same ordering key can also be redelivered even if already acknowledged ([00:01:04]-[00:02:09]).
• Streaming pull and flow control work together: A persistent connection receives messages continuously, while maximum-outstanding-message settings protect an underprovisioned subscriber and avoid starving peers ([00:02:09]-[00:03:13]).

Current-use note: Verify current subscription types, authentication, scaling, ordering, and client flow-control behavior. Size intake from real processing capacity and recovery behavior rather than treating maximum throughput as the only objective.

Full video: https://www.youtube.com/watch?v=aHc-DOP43a8(opens in a new tab)