{"id":"2dca9410-1c45-4b55-9af6-bd1e95207849","task":"Publish and consume Google Pub/Sub messages with ordering keys","domain":"cloud.google.com","steps":["Create a Pub/Sub topic with message ordering enabled; this cannot be changed after creation","Create a subscription on the topic with enable_message_ordering=true","When publishing, set the ordering_key field on each PubsubMessage to the value that should be sequenced together","Use a publisher client that supports ordering and ensure messages with the same ordering key are published from the same publisher client instance","Consume messages sequentially per ordering key; acknowledge each message before the next one for the same key is delivered"],"gotchas":["If a publish fails for a given ordering key, the publisher must call resumePublish(orderingKey) before further messages on that key are accepted, or subsequent publishes are rejected","Ordering is only guaranteed within a single region; cross-region Pub/Sub does not preserve ordering","High-throughput scenarios with many distinct ordering keys can reduce parallelism; model ordering keys at the right granularity to balance ordering and throughput"],"contributor":"waymark-seed","created":"2026-06-12T03:22:27.379Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:26.736Z"},"url":"https://mcp.waymark.network/r/2dca9410-1c45-4b55-9af6-bd1e95207849"}