CloudKit JS

If you've ever built an application for iOS using Swift, you've probably heard of CloudKit. It's Apple's BaaS (Backend as a Service) that powers iCloud, providing authentication, a private database, a public database and structured asset storage services.

Apple give pretty generous usage to these services if you're enrolled in the Apple Developer Program, making it the perfect choice for a backend for your iOS application.

But if you ever find yourself needing to perform maintenance tasks on your database (seeding data, backing up data), the developer experience is less than ideal.

I faced exactly this problem when I was building Cycle Parking. I needed a way to migrate the tens of thousands of cycle parking spaces from my own data sources into CloudKit.

Now, Apple do provide a REST API for interacting with CloudKit, but to do the most basic DB tasks required some convoluted API calls.

In a classic Dan move, I decided to completely over-engineer this and build a package.

CloudKit JS is a Javascript library that makes it super easy for develoeprs to interact with their CloudKit database.

Once you've provided the authentication token by following the instructions in the repository's README file, we can begin making database operations.

const orm = new CloudKitJs({
    containerName: secrets.containerName,
    keyId: secrets.keyId,
    privateKeyPath: secrets.privateKeyPath,
})

orm.createRecord({
    recordType: "Recipes",
    fields: {
        recipeName: {
            value: "Cacio e Pepe",
        },
        ingredients: {
            value: [
                "Pasta",
                "Pecorino Romano",
                "Black Pepper",
            ],
        },
        method: {
            value: [
                "Boil water",
                "Add pasta",
                "Grate cheese",
                "Add cheese and pepper to pasta",
                "Mix",
            ],
        },
        timeToCook: {
            value: 15
        },
        rating: {
            value: 5
        },
    },
})

Probably my favourite part of the library is how easy it makes asset uploading.

If you were to use Apple's REST API directly, uploading an asset is done with three API calls:

• Requesting the URL to upload the asset to
• Uploading the image to the given URL
• Updating the record to attach the asset reference

But with CloudKit JS, it's simple:

    await orm.uploadAssetFromUrl(
        "Recipe", // The record type
        "image", // The name of the field where the asset should be stored
        imageUrl, // The URL of the asset
        recordName, // The name of the record relating to this asset
    )