Message Queues (13)
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What does it mean that web sockets are bidirectional? Why is this useful❓ 📁
- This enables the server to send real-time updates asynchronously, without requiring the client to submit a request each time. allows devices to send and receive continuous streams of data to and from any point on the network.
Does socket.io use HTTP? Why❓ 📁
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socket.ioserver will attach to an HTTP server so it can serve its own client code through /socket.io/socket.io.js. -
On top of the transport, it offers additional functionality like segmentation (namespaces, rooms), acknowledgements, broadcasts, etc.
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socket.iois a websocket library
What happens when a client emits an event❓ What happens when a server emits an event❓ 📁
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When a click event happens, run the callback function that inside the listen(.on).
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you can emit events on one side and register listeners on the other side.
socket.emitwill send back message to sender only,io.emitwill send message to all the client including sender- if you want to send message to all but not back to sender then
socket.broadcast.emit
What happens if a client “misses” an event❓ 📁
- will receive the response after he be connected
How can we mitigate this❓ 📁
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use Queue
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Server
- Is a computer program or device that provides a service to another computer program and its user, also known as the client. In a data center, the physical computer that a server program runs on is also frequently referred to as a server.
Socket
- Java Socket programming is used for communication between the applications running on different JRE. … Socket and ServerSocket classes are used for connection-oriented socket programming
Web Socket
- WebSocket is the communication Protocol that provides bidirectional communication between the Client and the Server over a TCP connection
OSI Model
- (Open Systems Interconnection Model) is a conceptual framework used to describe the functions of a networking system.
Rooms
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A room is an arbitrary channel that sockets can join and leave. It can be used to broadcast events to a subset of clients.
- You can call join to subscribe the socket to a given channel.
- use to or in to emitting/send sothing.(room or rooms)
- every socket in the room excluding the sender will get the event.
Reserved events:
- connect
- connect_error
- disconnect
- disconnecting
- newListener
- removeListener
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