Roku Request Executor

Callback based singleton HTTP client for Roku written in BrighterScript

Requirements

• Handles a queue of multiple simultaneous requests
• Safe to call from render thread
• proides a singleton, accessible globally
• Invokes a callback declared at call site with data from request
  • e.g.

    executorV2()@.enqueuePost(createPostRequest())
    
    function createPostRequest()
      request = createObject("roSGNode", "Request")
      request.headers = { "Content-Type": "application/json" }
      request.body = { randomNumber: StrI(Rnd(55) * 100) }
      request.callBack = {
        componentReference: m.componentReference
        functionName: "printResponse"
      }
      return request
    end function
    

• Throws an exception if a callback was provided but not function signature matches.

Lifecycle Sequence Diagram

sequenceDiagram
	note over Request: RequestNode w type, body, and callback
	RequestPort->>RequestPort: receiveEvents()
	note over RequestPort: for singleton's lifespan
	Request->>RequestPort: requestExecutorV2()@.enqueuePost(request)
	RequestPort->>RequestQueue: request
	alt there is an available TransferObject	
		RequestQueue->>TransferObjectPool: get TransferObject
		TransferObject->>TransferObject: sendRequest
		TransferObject->>RequestPort: processResponse
		note over RequestPort: request.invokeCallback (if present)
		TransferObject->>TransferObjectPool: return to pool
	else no TransferObjects available
		note over RequestQueue: no-op
	end

Loading

Gif demo

https://i.imgur.com/Rwge8PP.gif

To-do

• migrate to roPM
  • maybe--not sure how hard this will be
• review documentation to make sure it's still correct
• support other http Methods
  • maybe--we don't have an internal usecase so it's lower priority for me
• write unit tests
  • I'm unfamiliar with unit testing in bs/brs, but this feels valuable to me