Front End Database

We use datascript to store all data for the front end.

When an Input Field is rendered

We write to the database the function that will validate the input field.

There is a global message queue. We publish messages on here when something happens that needs to be handled by a different part of the system.

For example, when an input field is updated, we publish that message on the queue. The message has the format:

{:component/id id
 :data/persist :local
 :component/value value
 :component/validation-fn validtn-fn
 :component/validate true}

We have a watcher that looks for messages that have the key/value pair:

:data/persist true

This will save the value into datascript.

When we see a message that has the key/value pair:

:component/validate true

We lookup the component by it’s id, and then pull out the value for the key: :component/validation-fn.

We call this function with the current value of the component.

We need a different part of the system to listen for messages that have the value:

That will save the information under the component key.

When modified, we send a message on the queue with the new value and the inputs id.