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Patterns for shared messages

You can store your events, commands and queries in any folder in your EventCatalog.

Here are some common usecases:

Messages defined by the service​

If you want to keep your message definition close to the service that producers or consumes it you can store them in the /services folder.

In the example below the OrderPlaced event, AddOrder command and GetOrder query are defined in the /services/Orders folder.

services/
  Orders/
    events/
      OrderPlaced/
        index.mdx
    commands/
      AddOrder/
        index.mdx
    queries/
      GetOrder/
        index.mdx

Define messages at a domain level​

If you want to share messages across multiple services you can define them in the /domains folder.

In the example below the OrderPlaced event, AddOrder command and GetOrder query are defined in the /domains/Orders folder.

domains/
  Orders/
     <!-- The domain documentation -->
    index.mdx
    <!-- Here we store our /events, /commands and /queries -->
    events/
      OrderPlaced/
        index.mdx

Define messages at a system level​

If you want to share messages across all your domains you can define them in the root of your catalog.

In the example below the OrderPlaced event, AddOrder command and GetOrder query are defined in the root of your catalog.

events/
  OrderPlaced/
    index.mdx
commands/
  AddOrder/
    index.mdx
queries/
  GetOrder/
    index.mdx