add correct default to rpcHost

[macfarla]

PR description

set the default value for the rpc Http Host CLI option so that it gets initialized correctly

Fixed Issue(s)

fixes #7721

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[macfarla]

With this PR

besu --p2p-host=9.9.9.9 --metrics-enabled

2024-10-04 14:17:10.890+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 127.0.0.1:9545
2024-10-04 14:17:10.917+10:00 | vert.x-eventloop-thread-1 | INFO  | MetricsHttpService | Metrics service started and listening on 127.0.0.1:9545
2024-10-04 14:17:10.919+10:00 | main | INFO  | EngineJsonRpcService | Starting JSON-RPC service on 127.0.0.1:8551
2024-10-04 14:17:10.922+10:00 | vert.x-eventloop-thread-1 | INFO  | EngineJsonRpcService | JSON-RPC service started and listening on 127.0.0.1:8551

[macfarla]

Without this PR

 besu --p2p-host=9.9.9.9 

...
2024-10-04 15:24:57.477+10:00 | main | INFO  | Runner | Starting external services ...
2024-10-04 15:24:57.478+10:00 | main | INFO  | EngineJsonRpcService | Starting JSON-RPC service on 9.9.9.9:8551

and with metrics enabled, since metrics service is initalized first

 besu --p2p-host=9.9.9.9 --metrics-enabled

2024-10-04 14:16:29.992+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 9.9.9.9:9545

[siladu]

Without this PR
and with metrics enabled, since metrics service is initalized first

 besu --p2p-host=9.9.9.9 --metrics-enabled

2024-10-04 14:16:29.992+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 9.9.9.9:9545

I don't see this behaviour on the latest main:

$ $BESU --p2p-host=9.9.9.9 --metrics-enabled
...
# Besu version 24.10-develop-81f9fc9                                                               #
...
2024-10-04 16:26:19.020+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 127.0.0.1:9545
2024-10-04 16:26:19.053+10:00 | vert.x-eventloop-thread-1 | INFO  | MetricsHttpService | Metrics service started and listening on 127.0.0.1:9545
2024-10-04 16:26:19.054+10:00 | main | INFO  | EngineJsonRpcService | Starting JSON-RPC service on 9.9.9.9:8551

Did you test before 911f12e perhaps?

[siladu]

It fixes the issue so will approve it.

TBH, it's not clear to me why #7682 broke it and why this is the correct fix and so I don't have confidence there aren't other issues with #7682

[siladu]

Nice 👍

How do we know other host configs aren't affected as well?

[macfarla]

Without this PR
and with metrics enabled, since metrics service is initalized first

 besu --p2p-host=9.9.9.9 --metrics-enabled

2024-10-04 14:16:29.992+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 9.9.9.9:9545

I don't see this behaviour on the latest main:

$ $BESU --p2p-host=9.9.9.9 --metrics-enabled
...
# Besu version 24.10-develop-81f9fc9                                                               #
...
2024-10-04 16:26:19.020+10:00 | main | INFO  | MetricsHttpService | Starting metrics http service on 127.0.0.1:9545
2024-10-04 16:26:19.053+10:00 | vert.x-eventloop-thread-1 | INFO  | MetricsHttpService | Metrics service started and listening on 127.0.0.1:9545
2024-10-04 16:26:19.054+10:00 | main | INFO  | EngineJsonRpcService | Starting JSON-RPC service on 9.9.9.9:8551

Did you test before 911f12e perhaps?

yes have re-tested and it's only the JSON-RPC host that's affected

besu --p2p-host=9.9.9.9 --metrics-push-enabled

2024-10-08 11:46:30.657+10:00 | main | INFO  | MetricsPushGatewayService | Starting metrics push gateway service pushing to 127.0.0.1:9001
2024-10-08 11:46:30.659+10:00 | main | INFO  | EngineJsonRpcService | Starting JSON-RPC service on 9.9.9.9:8551