A useful Firebase-Cloud-Firestore Wrapper with Codable.

Developed by @sgr-ksmt

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Table of Contents

• Feature
• Usage
  • Basic Usage
  • Advanced Usage
• Installation
• Dependencies
• Road to 1.0
• Development
• Communication
• Credit
• License

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Feature

• 🙌 Support Codable (Use FirebaseFirestoreSwift inside).
• 🙌 Provide easy-to-use methods for CRUD, Batch, Transaction.
• 🙌 Support array-union/array-remove.
• 🙌 Support FieldValue.increment.
• 🙌 Support FieldValue.delete().
• 🙌 Support KeyPath based query.

Use Swift features(version: 5.1)

• 💪 @propertyWrapper: SE-0258
• 💪 Key Path Member Lookup: SE-0252

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Usage

• 👉 Example App

Basic Usage

The type of Document must be conformed to the SnapshotData protocol.
SnapshotData protocol inherits Codable. For example:

struct Product: SnapshotData {
    var name: String = ""
    var desc: String?
    var price: Int = 0
    var attributes: [String: String] = [:]
}

It is convenient to define DocumentPath<T> and CollectionPath<T>.
Define path for extension of DocumentPaths or CollectionPaths.

extension CollectionPaths {
    static let products = CollectionPath<Product>("products")
}

extension DocumentPaths {
    static func product(_ productID: String) -> DocumentPath<Product> {
        CollectionPaths.products.document(productID)
    }
}

Create Snapshot with model that comformed to SnapshotData and path.

let product = Snapshot<Product>(data: Product(), path: CollectionPath.products)

In short 👇

let product = Snapshot(data: .init(), path: .products)

You can save it by calling create(completion:)

product.create { error in
    if let error = error {
        print("error", error)
        return
    }
    print("created!")
}

FireSnapshot also provides read(get document(s)/listen document(s)), write(update/delete), write with batch and transaction

// Update document
product.update { error in
    if let error = error {
        print("error", error)
        return
    }
    print("updated!")
}

// Delete document
product.delete { error in
    if let error = error {
        print("error", error)
        return
    }
    print("deleted!")
}

// Get document
Snapshot.get(.product("some_product_id")) { result in
    switch result {
    case let .success(product):
        print(product.name)
    case let .failure(error):
        print(error)
    }
}

// Listen document
let listener = Snapshot.listen(.product("some_product_id")) { result in
    switch result {
    case let .success(product):
        print("listened new product", product.name)
    case let .failure(error):
        print(error)
    }
}

// Get documents
Snapshot.get(.products) { result in
    switch result {
    case let .success(products):
        print(products.count)
    case let .failure(error):
        print(error)
    }
}

// Listen documents
let listener = Snapshot.listen(.products) { result in
    switch result {
    case let .success(products):
        print("listened new products", products.count)
    case let .failure(error):
        print(error)
    }
}

If you can read/write timestamp such as createTime and updateTime, model must be conform to HasTimestamps protocol.

struct Product: SnapshotData, HasTimestamps {
    var name: String = ""
    var desc: String?
    var price: Int = 0
    var attributes: [String: String] = [:]
}

let product = Snapshot(data: .init(), path: .products)
// `createTime` and `updateTime` will be written to field with other properties.
product.create()

Snapshot.get(product.path) { result in
    guard let p = try? result.get() else {
        return
    }

    // optional timestamp value.
    print(p.createTime)
    print(p.updateTime)

    // `updateTime` will be updated with other properties.
    p.update()
}

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Advanced Usage

@IncrementableInt / @IncrementableDouble

If you want to use FieldValue.increment on model, use @IncrementableInt(Double).

• The type of @IncrementableInt property is Int64.
• The type of @IncrementableDouble property is Double.

extension CollectionPaths {
    static let products = CollectionPath<Model>("models")
}

struct Model: SnapshotData {
    @IncrementableInt var count = 10
    @IncrementableDouble var distance = 10.0
}

Snapshot.get(.model(modelID)) { result in
    guard let model = try? result.get() else {
        return
    }
    // Refer a number
    print(model.count) // print `10`.
    print(model.distance) // print `10.0`.

    // Increment (use `$` prefix)
    model.$count.increment(1)
    print(model.count) // print `11`.
    model.update()

    model.$distance.increment(1.0)
    print(model.distance) // print `11.0`.
    model.update()

    // Decrement
    model.$count.increment(-1)
    print(model.count) // print `9`.
    model.update()

    model.$distance.increment(-1.0)
    print(model.distance) // print `9.0`.
    model.update()

    // if you want to reset property, use `reset` method.
    model.$count.reset()
}

@AtomicArray

If you want to use FieldValue.arrayUnion or FieldValue.arrayRemove, use @AtomicArray.

The type of @AtomicArray's element must be conformed to Codable protocol.

extension CollectionPaths {
    static let products = CollectionPath<Model>("models")
}

struct Model: SnapshotData {
    @AtomicArray var languages: [String] = ["en", "ja"]
}

Snapshot.get(.model(modelID)) { result in
    guard let model = try? result.get() else {
        return
    }

    // Refer an array
    print(model.languages) // print `["en", "ja"]`.

    // Union element(s)
    model.$languages.union("zh")
    print(model.count) // print `["en", "ja", "zh"]`.
    model.update()

    // Remove element(s)
    model.$languages.remove("en")
    print(model.count) // print `["ja"]`.
    model.update()

    // if you want to reset property, use `reset` method.
    model.$languages.reset()
}

@DeletableField

IF you want to use FieldValue.delete, use @DeletableField.

extension CollectionPaths {
    static let products = CollectionPath<Model>("models")
}

struct Model: SnapshotData {
    var bio: DeletableField<String>? = .init(value: "I'm a software engineer.")
}

Snapshot.get(.model(modelID)) { result in
    guard let model = try? result.get() else {
        return
    }

    print(model.bio?.value) // print `Optional("I'm a software engineer.")`

    // Delete property
    model.bio.delete()
    model.update()
}

// After updated
Snapshot.get(.model(modelID)) { result in
    guard let model = try? result.get() else {
        return
    }

    print(model.bio) // nil
    print(model.bio?.value) // nil
}

NOTE: Normally, when property is set to nil, {key: null} will be written to document,
but when using FieldValue.delete, field of key will be deleted from document.

KeyPath-based query

You can use KeyPath-based query generator called QueryBuilder if the model conform to FieldNameReferable protocol.

extension CollectionPaths {
    static let products = CollectionPath<Product>("products")
}

struct Product: SnapshotData, HasTimestamps {
    var name: String = ""
    var desc: String?
    var price: Int = 0
    var deleted: Bool = false
    var attributes: [String: String] = [:]
}

extension Product: FieldNameReferable {
    static var fieldNames: [PartialKeyPath<Mock> : String] {
        return [
            \Self.self.name: "name",
            \Self.self.desc: "desc",
            \Self.self.price: "price",
            \Self.self.deleted: "deleted",
        ]
    }
}

Snapshot.get(.products, queryBuilder: { builder in
    builder
        .where(\.price, isGreaterThan: 5000)
        .where(\.deleted, isEqualTo: false)
        .order(by: \.updateTime, descending: true)
}) { result in
    ...
}

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Installation

• CocoaPods

pod 'FireSnapshot', '~> 0.8.0'

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Dependencies

• Firebase: v6.11.0 or higher.
• FirebaseFirestoreSwift: Fetch from master branch.
• Swift: 5.1 or higher.

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Road to 1.0

• Until 1.0 is reached, minor versions will be breaking 🙇‍.

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Development

Setup

$ git clone ...
$ cd path/to/FireSnapshot
$ make
$ open FireSnapshot.xcworkspace

Unit Test

Start Firestore Emulator before running Unit Test.

$ npm install -g firebase-tools
$ firebase setup:emulators:firestore
$ cd ./firebase/
$ firebase emulators:start --only firestore
# Open Xcode and run Unit Test after running emulator.

or, run ./scripts/test.sh.

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Communication

• If you found a bug, open an issue.
• If you have a feature request, open an issue.
• If you want to contribute, submit a pull request.:muscle:

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Credit

FireSnapshot was inspired by followings:

• starhoshi/tart
• alickbass/CodableFirebase

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License

FireSnapshot is under MIT license. See the LICENSE file for more info.