Crate rpc_toy

A Toy RPC framework that is bug-prone, super slow, and hard to use

But.. why?

Well, I’m taking a class on distributed systems now and RPC was a topic so… What’s best to understand a topic that to implement it?

So that’s where this came from. I repeat, this is toy. please no one use this

General Information:

This library is built upon two main protocols/concepts:

• JSON serialization
• TCP

JSON is used for everything as a convinient (yet probably slow) way to serialize data types to strings. Then, the strings are converted to UTF8 bytes and passed down. TCP is our choice of transport layer protocol. It makes moving the bytes from point A to point B easy.. So why not. Again, this is a toy. Not meant to be used for benchmarking or anything

How to use:

This library includes two main structs a Client struct and a Server struct. a server is meant to register RPC functions, and the client can then call them.

Examples:

Example Client

use rpc_toy::Client;
// You can create a new client using "new"
let mut client = Client::new("127.0.0.1:3001").unwrap();
// All arguments have to be passed in as a slice of `serde_json::Value`s
let one = serde_json::to_value(1u32).unwrap();
let two = serde_json::to_value(2u32).unwrap();
let args = vec![one, two];
// Use the `call` function to call remote procedures
let res = client.call("Add", &args).unwrap();

let three: u32 = serde_json::from_value(res.unwrap()).unwrap();
assert_eq!(three, 3);

Example Server

use rpc_toy::Server;
let mut server = Server::new();
server.register("Add", |args| {
    let one = args.get(0).unwrap();
    let two = args.get(1).unwrap();
    let one = serde_json::from_value::<u32>(one.clone()).unwrap();
    let two = serde_json::from_value::<u32>(two.clone()).unwrap();
    let three = one + two;
    return Some(serde_json::to_value(three).unwrap());
});
server.listen("127.0.0.1:3001").unwrap();

Message encodings:

The client message encoding
32 bits for the length of the function name
the name of the function
The length of the argument, or zero for termination
The argument encoded as JSON string utf8
second argument length, or zero for termination
Repeats until termination …

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The server message encoding
32 bits for the length of the response
The response encoded as a JSON string utf8

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Structs

• Client
  An RPC client This is the main struct that should be used for implementing an RPC client.
• Server
  A struct representing an RPC server, this is to be used to implement the server.

Enums

• Error
  An error representing all the errors that could happen