Multi-leader store without a conflict policy

warningmulti-leader-store-without-conflict-policy

Multi-leader replication accepts concurrent writes in several regions. With no conflict resolution policy declared, divergent replicas are reconciled by accident rather than by design.

Severity: warning
Selects: every node of kind nosql-database
Components in scope: 47

What it checks

It looks at every node of kind nosql-database, and fires when:

— all of these hold:
— the node's `replication` is "multi-region-multi-leader"
— any of these hold:
— the node's `conflictResolution` has no value
— the node's `conflictResolution` is "none"

Message

Store '{{node.id}}' is multi-leader across regions with no conflict resolution policy. Declare last-writer-wins, vector-clock or app-merge.

{{node.id}} style paths are filled in from the node, the edge or the design the finding is about.

Applies to · 47 components

NoSQL database nosql-database

Tripped by · 10

Reference designs whose broken twin names this rule in its header. The gate reads the same header, and fails when a rule no design trips.

ad-click-aggregationreference datadog-huskyreference instagram-feedreference linkedin-kafkareference netflix-streamingreference object-storagereference paypal-paymentsreference snapchat-platformreference tiktok-recommendationreference wikipediareference

Source

1# yaml-language-server: $schema=../schema/rule.schema.json
2# Multi-leader replication accepts concurrent writes in several regions. Without a declared
3# conflict resolution policy, divergent replicas are reconciled by accident.
4# Tripped by: designs/object-storage.broken.yaml
5schemaVersion: "1"
6type: "rule"
7id: "multi-leader-store-without-conflict-policy"
8severity: "warning"
9select:
10  node:
11    kind: "nosql-database"
12when:
13  all:
14    - prop: "replication"
15      equals: "multi-region-multi-leader"
16    - any:
17        - prop: "conflictResolution"
18          exists: false
19        - prop: "conflictResolution"
20          equals: "none"
21message: "Store '{{node.id}}' is multi-leader across regions with no conflict resolution policy. Declare last-writer-wins, vector-clock or app-merge."

The same page as markdown, for an agent: /catalogue/rules/multi-leader-store-without-conflict-policy.md