JusticeTech System

I have received alot of questions regarding AWS Maybe we will hoaver around it soon

You'd hardly see a free telegram channel that teaches stuffs the way we do here Most of them are paid

I had an international interview yesterday with a tech company from Hong Kong which has several teams in New York, united state. The interview that is meant to last for 30 minutes was successfully concluded within 10 minutes because I was able to provide answers to all the questions that was being asked. Meanwhile this are the little little questions that was been asked

Always attempt questions like this, it helps most of the time, always engage in intelligent conversations like this, you are never too small to interact intelligently Do your research and drop your view that is how you grow

In most modified WhatsApp like JMWhatsApp, GBWhatsApp etc there is a feature called anti delete which is responsible for messages are not being deleted for recipient. How was that possible? Or WhatsApp bot developer, I believe you have antidelete message feature on your bot, how were you able to implement that? Will love to hear and learn from you all too Welcome to JusticeTech System

But I have a question

I think i have been able to simplify this as much as possible

Summary When a delete for everyone request is made, WhatsApp server coordinate the deletion but the actual message removal happens on each users device using the message id. That's how WhatsApp can support delete for everyone without breaking end-to-end encryption.

What happened behind the scene? 5. Handle offline users If someone is offline the deleted request is temporary queued and as soon as they reconnect the event is delivered and their apps applies the deletion locally.

Now what is someone is offline? I love technology 😀😀

What happened behind the scene? 4. Notify Every Recipient Here the Delete request is delivered to everyone who received that message, that is each recipient WhatsApp app locates the matching message id and the delete the message.

Hope you are following?

What happened behind the scene? 3. Create a delete event Instead of reading or modifying the encrypted message, the server create a delete request linked to that message id. The reason being since the message is end-to-end encrypted then there's no point for the server to start attempting to decrypt the message.

What happened behind the scene? 2. Verify the request Before processing the Delete request, the backend verifies this 3 state: - Is the request coming from the original sender? - is it within the allow delete time window? - Does the message exits!? Before the request can be accepted

You can go back using that link to understand what Idempotency entails So let's proceed

What actually happened behind the scene? 1. Delete request When you use or tap the Delete for everyone, what happens is that your app send a small request containing the message id to the server. The message itself won't be sent again because every message already has a unique identifier Remember my teaching on Idempotency https://t.me/justicetechsystem/1627

I am going to break this down using 5 step logics So let's go

Now get your writing materials

If WhatsApp chat is really end-to-end encrypted, how does "Delete for everyone" works if WhatsApp can't really read your messages?

Posting directly from the dashboard This is Miss Chatra on WhatsApp