QuakesDataClient

Similar to our AnimalsDataClient executable, we can build a QuakesDataClient executable for testing against a “real” SwiftData database. Select the QuakesData package and open Sources/QuakesDataClient/main.swift.

Here is our work to construct a LocalStore and a RemoteStore:

//  main.swift

import Foundation
import QuakesData
import Services

extension NetworkSession: RemoteStoreNetworkSession {
  
}

func makeLocalStore() throws -> LocalStore {
  if let url = Process().currentDirectoryURL?.appending(
    component: "default.store",
    directoryHint: .notDirectory
  ) {
    return try LocalStore(url: url)
  }
  return try LocalStore()
}

func makeRemoteStore() -> RemoteStore<NetworkSession<URLSession>> {
  let session = NetworkSession(urlSession: URLSession.shared)
  return RemoteStore(session: session)
}

func main() async throws {
  let localStore = try makeLocalStore()
  let remoteStore = makeRemoteStore()
  
  let localQuakes = try await localStore.fetchLocalQuakesQuery()
  print(localQuakes)
  
  let remoteQuakes = try await remoteStore.fetchRemoteQuakesQuery(range: .allHour)
  print(remoteQuakes)
}

try await main()

The Services module is provided along with our Workspace from the ImmutableData-Samples repo. This module provides a NetworkSession class that simplifies fetching and serializing data models from a remote server. Our goal with this tutorial is to teach the ImmutableData architecture. Networking code is interesting, but does not really need to block that main goal. You are welcome to explore other solutions for networking in your own products. We provide the Services module just to keep things easy for our tutorial.

Once we have a NetworkSession instance, we use that to create a RemoteStore. We create a LocalStore using a similar pattern to what we saw in AnimalsDataClient.

Our main function constructs a LocalStore and a RemoteStore. We now have the option to begin performing queries and mutations. Try it for yourself. You can fetch earthquakes from USGS, insert those earthquakes in a local database, then run your executable again and confirm the mutations were persisted.