KurrentDB

This is unofficial Kurrent (formerly: EventStore) Database gRPC Client SDK, developing in Swift language

Kurrent is the first and only event-native data platform. It is built to store and stream data as events for use in downstream use cases such as advanced analytics, microservices and AI/ML initiatives.

Swift is a general-purpose programming language that’s approachable for newcomers and powerful for experts. It is fast, modern, safe, and a joy to write.

Implementation Status

Client Settings

Feature	Implemented
ConnectionString parsed	✅
Endpoint (ip, port)	✅
UserCredentials ( username, password )	✅
Gossip ClusterMode

Stream

Feature	Implemented
Append	✅
Read	✅
Metadata	✅
Subscribe Specified Stream	✅
Subscribe All Stream	✅
BatchAppend	✅

Projection

Feature	Implemented
Create	✅
Update	✅
Result	✅
Delete	✅
Enable	✅
Disable	✅
State	✅
Statistics	✅
Reset	✅
RestartSubsystem	✅

PersistentSubscriptions

Feature	Implemented
Create	✅
Delete	✅
GetInfo	✅
List	✅
Read	✅
ReplayParked	✅
RestartSubsystem	✅
Subscribe	✅
Update	✅

User

Feature	Implemented
Create	✅
Details	✅
Disable	✅
Enable	✅
Update	✅
ChangePassword	✅
ResetPassword	✅

Getting the library

Swift Package Manager

The Swift Package Manager is the preferred way to get EventStoreDB. Simply add the package dependency to your Package.swift:

dependencies: [
  .package(url: "https://github.com/gradyzhuo/KurrentDB-Swift.git", from: "1.0.0")
]

...and depend on "KurrentDB" in the necessary targets:

.target(
  name: ...,
  dependencies: [.product(name: "KurrentDB", package: "KurrentDB-Swift")]
]

Examples

The library name to import.

import KurrentDB

ClientSettings

// Using a client settings for a single node configuration by parsing a connection string.
let settings: ClientSettings = .parse(connectionString: "esdb://admin:changeit@localhost:2113")

// convenience 
let settings: ClientSettings = "esdb://admin:changeit@localhost:2113".parse()

// using string literal 
let settings: ClientSettings = "esdb://admin:changeit@localhost:2113"

//using constructor
let settings: ClientSettings = .localhost()


// settings with credentials
let settings: ClientSettings = .localhost(userCredentials: .init(username: "admin", 
                                                                   password: "changeit")

//settings with credentials with adding ssl file by path
let settings: ClientSettings = .localhost(userCredentials: .init(username: "admin", 
                                                                            password: "changeit"), 
                                                                 trustRoots: .file("...filePath..."))

//or add ssl file with bundle
let settings: ClientSettings = .localhost(userCredentials: .init(username: "admin", 
                                                                 password: "changeit"), 
                                                                 trustRoots: .fileInBundle(forResource: "ca", 
                                                                                           withExtension: "crt", 
                                                                                           inBundle: .main))

Appending Event

// Import packages of KurrentDB.
import KurrentDB

// Using a client settings for a single node configuration by parsing a connection string.
let settings: ClientSettings = .localhost()

// Create the data array of events.
let events:[EventData] = [
    .init(id: .init(uuidString: "b989fe21-9469-4017-8d71-9820b8dd1164")!, eventType: "ItemAdded", model: ["Description": "Xbox One S 1TB (Console)"]),
    .init(id: .init(uuidString: "b989fe21-9469-4017-8d71-9820b8dd1174")!, eventType: "ItemAdded", model: "Gears of War 4")]

// Append two events with one response
let client = KurrentDBClient(settings: .localhost())
try await client.appendStream(on: "stream_for_testing", events: events){
    $0.revision(expected: .any)
}

Read Event

// Import packages of EventStoreDB.
import KurrentDB

// Using a client settings for a single node configuration by parsing a connection string.
let settings: ClientSettings = .localhost()

// Read responses of event from specified stream.
let responses = try await client.readStream(on: "stream_for_testing", startFrom: .start){
    $0.backward()
}

// loop it.
for try await response in responses {
    //handle response
    if let readEvent = try response.event {
        //handle event
    }
}

PersistentSubscriptions

Create

// Import packages of EventStoreDB.
import KurrentDB

// Using a client settings for a single node configuration by parsing a connection string.
let settings: ClientSettings = .localhost()

// Build a persistentSubscriptions client.
let client = KurrentDBClient(settings: settings)

// the stream identifier to subscribe.
let streamIdentifier = StreamIdentifier(name: UUID().uuidString)

// the group of subscription
let groupName = "myGroupTest"

let persistentSubscription = client.streams(of: .specified(streamIdentifier)).persistentSubscriptions(group: groupName)

// Create it to specified identifier of streams.
try await persistentSubscription.create()

Subscribe

// Import packages of EventStoreDB.
import KurrentDB

// Using a client settings for a single node configuration by parsing a connection string.
let settings: ClientSettings = .localhost()

// Build a persistentSubscriptions client.
let client = KurrentDBClient(settings: settings)

// the stream identifier to subscribe.
let streamIdentifier = StreamIdentifier(name: UUID().uuidString)

// the group of subscription
let groupName = "myGroupTest"

let persistentSubscription = client.streams(of: .specified(streamIdentifier)).persistentSubscriptions(group: groupName)

// Subscribe to stream or all, and get a subscription.
let subscription = try await persistentSubscription.subscribe()

// Loop all results by subscription.events
for try await result in subscription.events {
    //handle result
    // ...
    
    // ack the readEvent if succeed
    try await subscription.ack(readEvents: result.event)
    // else nack thr readEvent if not succeed.
    // try await subscription.nack(readEvents: result.event, action: .park, reason: "It's failed.")
}