Rescript-Dexie

Rescript bindings to the easy-to-use Dexie wrapper of IndexedDB.

These bindings are not complete, but everything required for basic IndexedDB access should be working, including:

• Define fully typed table schemas
• Version and upgrade schemas
• Create, update, delete records (including bulk operations)
• Query by index
• Query using criteria
• Query using where clauses
• Perform operations on the resulting Collections
• Execute inside Transactions
• React live queries (optional, with dexie-react-hooks installed)

Some of the more complex pieces of Dexie are missing from these bindings:

• Translation of Dexie's JS error types into a Rescript-friendly paradigm
• Dexie Hooks API or DBCore Middleware
• Syncables
• Addons, including Dexie Cloud

A couple things I haven't tested yet:

• Not sure if things like compound primary keys are working
• Probably schema upgrades will get confused when dealing with 'before' and 'after' types

Quick Start

Start by defining a small module for each table in your database, that describes the type of the id field, the structure of each record, and the name of the table:

module FriendSchema = {
  type id = int
  type t = {
    id: option<int>,
    name: string,
    color: [#Blue | #Red | #Purple],
  }
  let tableName = "friends"
}

Use the MakeTable functor to create a table for each schema:

module Friend = Dexie.Table.MakeTable(FriendSchema)

Construct a Dexie instance with the IndexedDB name:

let dexie = Dexie.Database.make(`hello dexie ${someNumber}`)

Describe the Dexie schema for each of your tables using an array of (name, schema) tuples:

let schema = [("friends", "++id,name,birthdate,color"), ...]

Create your initial version of the database and open it:

dexie
->Dexie.Database.version(1)
->Dexie.Version.stores(schema)
->ignore

dexie->Dexie.Database.opendb->ignore

Add and query your tables using the module you created with the MakeTable functor. Note that most functions return promises so you'll want to use async and await syntax.

Some things you can do:

dexie->Friend.bulkPut([
  {id: Some(1), name: "Chris", color: #Red},
  {id: Some(2), name: "Leroy", color: #Blue},
  {id: Some(3), name: "Jerome", color: #Purple},
  {id: Some(4), name: "Betty", color: #Purple},
])

dexie->Friend.add(None, name: "Xiao", color: #Blue)

dexie->Friend.getById(3)->Promise.then(friendOption => ...)

dexie
->Friend.where("name")
->Dexie.Where.anyOfIgnoreCase(["Leroy", "Xiao"])
->Dexie.Collection.first
->Promise.then(friend=> ...)

React live query hooks are also supported if you yarn add dexie-react-hooks:

let teamBlue = Dexie.LiveQuery.use0(() => {
  dexie->Friend.findByCriteria({color: #Blue})
})

There are hooks use0 through use7 that behave similarly to rescript-react's useEffect modelling.

Next Steps

I haven't documented this as thoroughly as I normally do in my projects. For the most part, follow Dexie's excellent documentation and assume the Rescript bindings are sane (or completely unavailable).

You can also refer to the unit tests to get a better idea of the things you can do with the bindings.

And there is a tiny React app in the examples/react folder.

Contributing

PRs and issues are welcome!

Testing

I use my rescript-zora library for testing. yarn test:watch should be all you need.

Releasing

This is for my reference:

• update the version in bsconfig.json
• bump the version in example/react
• np