subpub/

README

multirpc: subpub example

This example uses almost the same code of the HTTP+WS example but using a different transport: a libp2p custom protocol named subpub.

In the server side we just need to change the endpoint implementation ep := endpoint.SubPubEndpoint{}.

In the client side we'll use directly the subpub handle: sp := subpubtransport.SubPubHandle{} and a local HTTP server that will forward the POST body to the p2p network and write back the reply (if any).

   [ http client (curl) ]
             |
[ client localhost http server ] 
             |
       ( p2p network ) 
             |
         [ server ]

Let's start with the p2p server:

go run ./server --logLevel=debug

We'll see something like this (among other messages).

DEBUG   router/router.go:65     adding new handler hello for namespace 
DEBUG   router/router.go:65     adding new handler addkey for namespace 
DEBUG   router/router.go:65     adding new handler getsecret for namespace 
DEBUG   subpub/discovery.go:15  searching for SubPub group identity b935f02bc28165df3076ccd945fb70b0eed26b2902961c8222fcb4b9dd555aa8
INFO    subpub/discovery.go:95  advertising topic b935f02bc28165df3076ccd945fb70b0eed26b2902961c8222fcb4b9dd555aa8

Subpub is doing the p2p bootstraping and discovery using a shared secret between client and server (sharedSecret123), all data transfered will be encrypted using this key thus only nodes knowing the key will be able to join the p2p subnetwork.

Same as the HTTP+WS example, we add three handlers to the server, hello, addkey and getsecret which will be transparently handled by the router (no matter which transport we use).

Now let's start the p2p client which will listen to http://localhost:8080/p2p in order to send and recive messages using any HTTP client such as curl.

go run ./client --logLevel=debug

The p2p discovery process between client and server can take some seconds (or minutes), but they should find each other and create a direct connection.

DEBUG   subpub/discovery.go:41  found peer: Qmct2CptU82Xs64cousGNmr8gfPq27CZhJL64Af8WqgEXW
INFO    subpub/stream.go:34     connected to peer Qmct2CptU82Xs64cousGNmr8gfPq27CZhJL64Af8WqgEXW:/ip4/192.168.1.112/tcp/7788

Now we can use curl transparently with the client http local server.

 $ curl -X POST -d '{"method":"hello", "request":"1234"}' 127.0.0.1:8080/p2p

{"request":{"reply":"hello! got your message with ID 272","request":"272","timestamp":1611842897},"id":"272","signature":"676df15d26840ed665d074d545b9b3ec74ab47b5259a59dceac9a44d5b8cae2810a89e1228a93b178b270d240f7810fed8f9590699847c1c4cffc26b458ddae001"}