sera-slackbot/Bot/Controllers/SlackInteractionController.cs

using System;
using System.Text.Json;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Configuration;

using SlackAPI;

using sera_slackbot.Library;

namespace sera_slackbot.Controllers
{
    [ApiController]
    [Route("interaction")]
    [Produces("application/json")]
    public class SlackInteractionController : ControllerBase
    {
        private readonly ILogger<SlackEventController> logger;
        private readonly IConfiguration configuration;

        private SlackClient client;
        private BotCommandFactory factory;

        private JsonFileReader jsonFileReader;
        private JsonFileSaver jsonFileSaver;

        public SlackInteractionController(IConfiguration config, ILogger<SlackEventController> log)
        {
            configuration = config;
            logger = log;
            var token = configuration.GetSection("Slackbot").GetValue<string>("Bot-User-OAuth-Access-Token");
            this.jsonFileReader = new JsonFileReader(configuration);
            this.jsonFileSaver = new JsonFileSaver(configuration);
            client = new SlackClient(token);
            factory = new BotCommandFactory(this.jsonFileReader, this.jsonFileSaver);
        }

        [HttpGet]
        public IActionResult Get()
        {
            // Console.WriteLine("***Interaction***");
            // foreach (var header in Request.Headers)
            // {
            //     Console.WriteLine(header.Key + ": " + header.Value);
            // }

            dynamic response = new
            {
                name = "Slack Interaction Bot",
                code = StatusCodes.Status200OK,
                datetime = DateTime.Now
            };
            return Ok(response);
        }

        [HttpPost]
        public IActionResult HttpPost([FromForm] string payload)
        {
            var payloadObject = JsonSerializer.Deserialize<dynamic>(payload);

            dynamic response = new { code = StatusCodes.Status200OK };

            var typeProperty = payloadObject.GetProperty("type");
            var type = typeProperty.ToString();
            switch (type)
            {
                case "block_actions":
                    response = BlockActions(payloadObject);
                    break;
                default:
                    logger.LogError($"Unknown Interaction Type: '{type}' = {payload}");
                    break;
            }

            return StatusCode(response.code, response);
        }

        private dynamic BlockActions(dynamic payload)
        {
            JsonElement actions = payload.GetProperty("actions");

            var valueProperty = "";
            foreach (var action in actions.EnumerateArray())
            {
                valueProperty = action.GetProperty("value").ToString();
            }

            var actionHandler = valueProperty.Split(":")[0];
            var actionValue = valueProperty.Split(":")[1];

            var command = this.factory.CreateInteraction(actionHandler);
            return command.Interaction(client, payload, actionValue);
        }
    }
}