Explanation

This is a bot that constatly checks for replies to a main tweet and replies to these replies with a result of what the their replied text would generate in both SD & Dallee AI models.

Note to self

• Explain this better.

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Structure

[ Initial Tweet ]

• [ Reply tweet 1] → [fn] → [image: dalle2 & SD2]
• [ Reply tweet 2] → [fn] → [image: dalle2 & SD2]

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Implementation of [Fn]

• Success criteria
  • must act on a reply tweet only onces
  • must validate the tweet as a valid prompt
  • must be asynchronous (non-blocking)
  • must check if the reply user is following

Idempotency

• Poll every x mins and store unique reply id in the db

  • [cronJob]* (x mins) → [fn1]
  • [fn1: get unique replies and save to db]
    • → [Twitter: get replies to a tweet]
    • → [validation]
      • valid prompt
      • check reply user is following
    • → [Db: Find or create new record]
      • tweet_id [uniq]
      • text as prompt
      • openAiUrl
      • sdUrl
    • → [Callback: listen for creation of new record to the db] → (async)[fn2]
  • [fn2: handle getting image from prompt]
    • → [openAi: call open ai api]
      • prompt
      • callback url (/openai/{id}
      • id
    • → [sd2: call sd api]
      • prompt
      • callback url (/sd/{id}
      • id
  • [Api: callback url]
    • get id, url from callback
    • update the db
    • [onUpdate] → [fn3]
  • [fn3]
    • check if both have url values
    • tweet to tweet_id

• recieve a request with a callback url

• respond with request recieved

• when task (image generation) is complete

• send image urls to the callback url

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• Important comands:
  • $ firebase serve
  • $ firebase emulators:start
  • $ firebase deploy --only functions
  • $ ./ngrok http 5001 (in dir w ngrok installed)

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Notes:

https://www.youtube.com/watch?v=MjEam95VLiI Pubsub(publisher subscriber model) - Pub/Sub helps build robust, scalable systems of applications by integrating them asynchronously. Pub/Sub allows for having a retry mechanism when microserves are down. In this case the replicate API when attempting to create the text-to-art images.

CLoud pub/sub is a fully managed real time messaging service that allows you to send and recieve between independetn applications.

Using pub/sub within your acrichteture, microservices dont need to know about each other. The only thing needed is they need to pub/sub and recieving the right messages

If any microservce goes down pub/sub stores the message for 7 days/ until the microservice is back online/available.

Used Ngrox to forward http request. This is because firbase emulators dont use https(local testing)

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Pub sub is not needed, why?:

Pubsub is more like SNS than SQS therefore for GCP the equiv of SQS is cloud Tasks!

Persistence

• SQS : Messages are persisted for some duration is no consumer available. The retention period value is from 1 minute to 14 days. The default is 4 days.
• SNS : No persistence. Whichever consumer is present at the time of message arrival, get the message and the message is deleted. If no consumers available then the message is lost.

Choose SQS if:

• You need a simple queue with no particular additional requirements.
• Decoupling two applications and allowing parallel asynchronous processing.
• Only one subscriber is needed.