Server Driven Workflows

In SwiftUI

WorkflowView has an initializer that allows you to pass in an AnyWorkflow. AnyWorkflows can be decoded from Data using either JSONDecoder.decodeWorkflow(withAggregator:from:), or the DecodeWorkflow property wrapper.

You can use JSON, YAML, or any other key/value-based data formats to define a workflow with data provided you follow our schema.

Our schema plays well with VSCode if you copy examples from the repo.

When using server driven workflows be aware that your views will all be wrapped in an AnyView. This is not true when you define workflows in Swift. This could affect certain animations and potentially have a performance impact on SwiftUI.

NOTE: The APIs for SwiftCurrent all accept any form of Data. This means you are free to use your own data formats, but it also means that data does not necessarily have to come from a server. For example, you could feed it from a flat-file if you’re writing a white-labeled application.

What is an Aggregator?

FlowRepresentableAggregator is a simple protocol that identifies all types you wish to decode. It’s how SwiftCurrent can take data and convert it into a Workflow. You can either create your own aggregator or use our CLI utility.

Putting it all together

Step 1: Create your views

struct FirstView: View, FlowRepresentable, WorkflowDecodable {
    weak var _workflowPointer: AnyFlowRepresentable?

    var body: some View {
        Text("I am the first view!")
        Button("Proceed") { proceedInWorkflow() }
    }
}

struct SecondView: View, FlowRepresentable, WorkflowDecodable {
    weak var _workflowPointer: AnyFlowRepresentable?

    var body: some View {
        Text("I am the second view!")
        Button("Proceed") { proceedInWorkflow() }
    }
}

struct ThirdView: View, FlowRepresentable, WorkflowDecodable {
    weak var _workflowPointer: AnyFlowRepresentable?

    var body: some View {
        Text("I am the third view!")
    }
}

Step 2: Define your workflow

{ "$schema": "https://raw.githubusercontent.com/wwt/WorkflowSchema/main/workflow-schema.json", "schemaVersion": "v0.0.1", "sequence": [ { "flowRepresentableName": "FirstView", "launchStyle": "navigationLink", }, { "flowRepresentableName": "SecondView", "launchStyle": "navigationLink", }, { "flowRepresentableName": "ThirdView", "launchStyle": "navigationLink", } ] } 

Step 3: Use your workflow definition

let aggregator = SwiftCurrentTypeRegistry() // If you use the CLI this will be generated, if not you'll need to create your own, see the docs for `FlowRepresentableAggregator` for more information.
let data: Data = getDefinedWorkflow() // from server or flat-file
let workflow = try JSONDecoder().decodeWorkflow(withAggregator: aggregator, from: data)

// In your view
WorkflowView(workflow: workflow).embedInNavigationView() // Our data specified navigation links, so we need to wrap this in a navigation view for them to work.