feat: Add RethCliExt

[mattsse]

This provides a way to additional cli args to the reth cli.

This adds RethRpcServerArgsExt that can install additional modules to the configured transports.

Default is a noop.

This is only one part of making the cli/node builder customizable, and is only intended for installing additional rpc components easily.

In order to provide something like a node builder we'd need:

• an abstraction over Node command,
• additional traits that setup all the components

[codecov]

Codecov Report

Merging #3983 (88bf7b5) into main (1ac2f15) will decrease coverage by 0.10%.
Report is 2 commits behind head on main.
The diff coverage is 32.96%.

Files Changed	Coverage Δ
crates/rpc/rpc-builder/src/lib.rs	64.15% <0.00%> (-1.90%)	⬇️
bin/reth/src/cli/ext.rs	4.16% <4.16%> (ø)
bin/reth/src/args/rpc_server_args.rs	54.42% <68.75%> (-0.18%)	⬇️
bin/reth/src/cli/mod.rs	34.40% <100.00%> (ø)
bin/reth/src/node/mod.rs	12.27% <100.00%> (+0.28%)	⬆️

... and 13 files with indirect coverage changes

Flag	Coverage Δ
integration-tests	16.28% <0.00%> (-0.02%)	⬇️
unit-tests	64.12% <32.96%> (-0.09%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
reth binary	25.83% <51.72%> (-0.07%)	⬇️
blockchain tree	83.04% <ø> (ø)
pipeline	89.83% <ø> (ø)
storage (db)	74.27% <ø> (ø)
trie	94.70% <ø> (ø)
txpool	45.40% <ø> (-0.61%)	⬇️
networking	77.65% <ø> (-0.05%)	⬇️
rpc	58.36% <0.00%> (-0.17%)	⬇️
consensus	63.51% <ø> (ø)
revm	33.10% <ø> (ø)
payload builder	6.58% <ø> (ø)
primitives	87.91% <ø> (-0.03%)	⬇️

[onbjerg]

Going off of what we talked about 1 on 1 -

This makes sense for the time being, but we should try to move towards having an abstraction that reth node uses instead of having reth node be the abstraction. The reasoning is that you might want complete control over the CLI/how the components are configured, and using reth node as the abstraction also suffers the following issues:

• We'd need to add a flag/option for anything you would want to configure and probably hide most of them
• It is not easy to integrate reth node into an existing code base with stricter requirements

In general, we would eventually want to support swapping out the builder, txpool, enabling/disabling parts of the pipeline, adding/removing/overriding things in RPC etc and encapsulating that in Clap (or things on top of Clap) is probably quite hard

Sensitive to the fact that building a better abstraction that we can reuse for reth node is a complex task, so this will do for now

Wdyt?

[mattsse]

yes, I agree,

I think we should try to abstract the node start command (or rather configuring + launching the node) and then the default Cli node command is just one impl of that,
it should be possible however to make this in such a way that even the default cli node commands is configurable to some degree