To include attribute values of the resource in the message, pass a list of strings and attribute names. They will ultimately be joined with `:`. For example: ```elixir prefix "user" publish :create, ["created", :user_id] ``` This might publish a message to \"user:created:1\"" for example. For updates, if the field in the template is being changed, a message is sent to *both* values. So if you change `user 1` to `user 2`, the same message would be published to `user:updated:1` and `user:updated:2`. If there are multiple attributes in the template, and they are all being changed, a message is sent for every combination of substitutions. ## Template parts Templates may contain lists, in which case all combinations of values in the list will be used. Add `nil` to the list if you want to produce a pattern where that entry is ommitted. The atom `:_tenant` may be used. If the changeset has a tenant set on it, that value will be used, otherwise that combination of values is ignored. The atom `:_pkey` may be used. It will be a stringified, concatenation of the primary key fields, or just the primary key if there is only one primary key field. The atom `:_skip` may be used. It only makes sense to use it in the context of a list of alternatives, and adds a pattern where that part is skipped. ```elixir publish :updated, [[:team_id, :_tenant], "updated", [:id, nil]] ``` Would produce the following messages, given a `team_id` of 1, a `tenant` of `org_1`, and an `id` of `50`: ```elixir "1:updated:50" "1:updated" "org_1:updated:50" "org_1:updated" ```