Estuary RPC is an attempt to make an extremely simple (toy) RPC system for use between browsers and servers that:

• is typesafe, with all types simply defined in TS - meaning your code won't compile if the server or the client code is not invoked with the correct types for the given RPC call
• supports most desired operations between client and server (REST methods, status codes, file uploads, automatic authentication)
• doesn't have external dependencies

estuary-rpc-client defines the createApiClient method for translating your API metadata definition into a typesafe collection of async functions organized into a neat little object

This should be installed in your client project

npm install estuary-rpc-client

After following instructions for your common code, from the clientside, it is necessary merely to import { convertApiClient, ClientClosure } from "estuary-rpc-client"; and import your common definitions, and you will be able to create an instantion of your Api type with callable rpc methods:

const client = convertApiClient(exampleApiMeta) as ExampleApi<ClientClosure, unknown>;

ClientClosure serves as the closure to the individual calls, should it be necessary to add additional calling options such as a timeout. The methods can then be called with

• await client.foo.emptyPost() to send an empty post message
• const res = await client.foo.simpleGet(4); to retrieve a number response from the server
• const res = await client.foo.simpleGet(4, {timeout: 1000}); to set a timeout on that fetch call
• Streaming is a bit more complicated, but I have tried to make it as straightforward as possible -

import { openStreamHandler } from "estuary-rpc";

const streamHandler = await openStreamHandler(client.foo.simpleStream);

streamHandler.on("message", (val: boolean) =>
  console.log("Got message from server", val);
  streamHandler.close()
);
streamHandler.write("yooo");

• openStreamHandler serves as a bit of a simplification of the underlying use of the RPC method, which works natively like so:

import { Duplex } from "estuary-rpc";

const duplex = new Duplex<string, boolean>();
await client.foo.simpleStream(duplex);

const streamHandler = duplex.client;
streamHandler.on("message", (val: boolean) => {
  console.log("Got message from server", val);
  simpleStream.close()
});
streamHandler.write("yooo");