SwiftBlocksUI: SlashCows

SwiftBlocksUI is a way to write interactive Slack messages and modal dialogs (also known as Slack "applications") using a SwiftUI like declarative style.

Explained in blog article/tutorial: Instant “SwiftUI” Flavoured Slack Apps.

This repository contains the SlashCows demo, a Slack slash command that produces ASCII Cows. Moo!

How to Run

If swift-sh is installed,

a simple ./Sources/SlashCows/main.swift does the job.

Alternatively: swift run:

helge@Zini18 SlashCows (main)*$ swift run
2020-07-17T17:05:33+0200 notice μ.console : App started on port: 1337

How to Build

cd SlashCows
swift build

Full Source

#!/usr/bin/swift sh

import cows          // @AlwaysRightInstitute ~> 1.0.0
import SwiftBlocksUI // @SwiftBlocksUI        ~> 0.8.0

dotenv.config()

struct CowMessage: Blocks {
  
  @Environment(\.messageText) private var query
  
  private var cow : String {
    return cows.allCows.first(where: { $0.contains(query) })
        ?? cows.vaca()
  }
  
  var body: some Blocks {
    Group { // only necessary on Swift <5.3
      Preformatted {
        cow
      }

      Actions {
        Button("Delete!") { response in
          response.clear()
        }
        .confirm(message: "This will delete the message!",
                 confirmButton: "Cowsy!")
        
        Button("More!") { response in
          response.push { self }
        }
        Button("Reload") { response in
          response.update()
        }
      }
    }
  }
}

struct Cows: App {
  
  var body: some Endpoints {
    Group { // only necessary w/ Swift <5.3
      Use(logger("dev"),
          bodyParser.urlencoded(),
          sslCheck(verifyToken(allowUnsetInDebug: true)))

      Slash("vaca", scope: .userOnly) {
        CowMessage()
      }
    }
  }
}
try Cows.main()

Environment Variables

• SLACK_VERIFICATION_TOKEN (shared secret with Slack to verify requests)
• PORT (the port the app is going to start on, defaults to 1337)

Requirements

On Linux this currently requires a Swift 5.3 environment (swiftc crash, might be SR-12543).

On macOS it should work with Swift 5.2 (aka Xcode 11) and up, though 5.3 has some additional conveniences.

Who

SwiftBlocksUI is brought to you by the Always Right Institute and ZeeZide. We like feedback, GitHub stars, cool contract work, presumably any form of praise you can think of.