this pr adds CLI flag to allow the rpcdaemon to bind to a TCP port.
this is very useful if one wants to maintain a remote connection with
the rpcdaemon without using websocket. This is useful because a lot of
issues come with the websocket protocol (compression, max size, etc).
TCP socket gets around these things (it is just raw json over tcp
stream)
the rpc package already supports this, it was just a matter of adding
the bind.
try `echo
'{"jsonrpc":"2.0","method":"eth_blockNumber","id":"1","params":[""]}' |
nc localhost 8548` as a basic test
to test. Subscriptions are also working (idk how to send keepalives with
netcat)
the default rpc.(*Client).Dial method does not support TCP. I have not
included that in this PR. The code for such is as follow
```
// DialTCP create a new TCP client that connects to the given endpoint.
//
// The context is used for the initial connection establishment. It does not
// affect subsequent interactions with the client.
func DialTCP(ctx context.Context, endpoint string) (*Client, error) {
parsed, err := url.Parse(endpoint)
if err != nil {
return nil, err
}
ans := make(chan *Client)
errc := make(chan error)
go func() {
client, err := newClient(ctx, func(ctx context.Context) (ServerCodec, error) {
conn, err := net.Dial("tcp", parsed.Host)
if err != nil {
return nil, err
}
return NewCodec(conn), nil
})
if err != nil {
errc <- err
return
}
ans <- client
}()
select {
case err := <-errc:
return nil, err
case a := <-ans:
return a, nil
case <-ctx.Done():
return nil, ctx.Err()
}
}
// DialContext creates a new RPC client, just like Dial.
//
// The context is used to cancel or time out the initial connection establishment. It does
// not affect subsequent interactions with the client.
func DialContext(ctx context.Context, rawurl string) (*Client, error) {
u, err := url.Parse(rawurl)
if err != nil {
return nil, err
}
switch u.Scheme {
case "http", "https":
return DialHTTP(rawurl)
case "ws", "wss":
return DialWebsocket(ctx, rawurl, "")
case "tcp":
return DialTCP(ctx, rawurl)
case "stdio":
return DialStdIO(ctx)
case "":
return DialIPC(ctx, rawurl)
default:
return nil, fmt.Errorf("no known transport for URL scheme %q", u.Scheme)
}
}
```
let me know if you would like me to add this to the PR as well. the TCP
connection can then be established with `rpc.Dial("tcp://host:port")`
* Update README re. Engine API
* Remove obsolete code
* Don't apply --rpc.accessList to Engine API listener
* Simplify startAuthenticatedRpcServer
* Rename engine.* cmd flags to authrpc.* for consistency with geth
* More renamings
* Introduce --authrpc.vhosts flag
* Add eth/67
* Listen to eth/66 on a separate port
* Fix compilation error
* Fix cfg66.ListenAddr
* Update erigon ports in README
* Expose port 30304 in docker
* P2pProtocolVersionFlag instead of second sentry
* Remove "66 by default" from usage
* Small comment
