rpc_port ignored in the configuration

[Dinonard]

Issue Description

In case of a configuration such as this one:

  [[parachains.collators]]
  name = "collator1"
  command = "./some-collator"
  rpc_port = 6969

The RPC port value will be ignored, and instead a random one will be used.

I assume it's due to this code:

if (nodeSetup.substrateCliArgsVersion === SubstrateCliArgsVersion.V0) {
    portFlags["--rpc-port"] = (nodeSetup.rpcPort || RPC_HTTP_PORT).toString();
    portFlags["--ws-port"] = (nodeSetup.wsPort || RPC_WS_PORT).toString();
  } else {
    // use ws port as default
    const portToUse = nodeSetup.wsPort
      ? nodeSetup.wsPort
      : nodeSetup.rpcPort || RPC_HTTP_PORT;
    portFlags["--rpc-port"] = portToUse.toString();
  }

wsPort will always be defined, since in case it's omitted, a random one will be generated at that point.

It's also a bit confusing to specify ws_port in the config file - both WS & HTTP are RPC ports.
Maybe it would be better to use rpc_port and stop using the ws_port?

Steps to reproduce the issue

Just specify rpc_port in the config file, as explained in the issue description.

Describe the results you received

Random RPC port was used.

Describe the results you expected

The one I specified to be used.

Zombienet version

1.3.63

Provider

Native

Provider version

## For binaries
polkadot 0.9.43-a2b62fb872b

Upstream Latest Release

Yes

Additional environment details

None

Additional information

No response

Screenshots

No response

[pepoviola]

Hi @Dinonard, thanks for your feedback and to open this issue. Yes, the issue was introduced when we add support for diff cli args version, since in older versions of polkadot you can specify ws-port and rpc-port (paritytech/substrate#13384). We want to still support older versions so we keep the ws-port option, but we need to fix the way we calculate which port you want to use.

As workaround, if you set ws_port = 6969 the collator will use that port as rpc-port.
Thanks!!

[iulianbarbu]

This is a present issue when creating tomls that would be used with both zombienet-sdk and zombienet/cli. To start a network based on a toml, with zn-sdk, the nodes would need the rpc_port config. Setting both rpc_port and ws_port seems to not work well with zombienet-sdk, as in the nodes aren't started, while for zombienet/cli isn't an issue. So we either create the tomls with rpc_port for zombienet-sdk, or with ws_port for zombienet/cli.

I discovered this while working on: paritytech/polkadot-sdk#7257, and using the tomls with both zombienet/cli & zombienet-sdk is a requirement.

[pepoviola]

Hi @iulianbarbu, which version of polkadot are you using? the ws_port was deprecated long time ago and only rpc_port should be used in both version for the current polkadot version.
Thx!

[iulianbarbu]

I am using latest polkadot & polkadot-parachain, built from master. The thing is that I am not interested in using ws_port, but rpc_port, which I am doing with zombienet-sdk, but zombienet/cli is not accepting the rpc_port config.