Add retries to DNS lookup for enode hostnames

[sergerad]

Relates to #8188

• Move DNS resolution function to DNSNodeRecord::
• Add RetryStrategy struct for optional retries of node hostname DNS resolution
• Add RetryStrategy field to NodeConfig

[sergerad]

@Rjected the retry impl is in place here with some tests.

Next I am thinking of adding the relevant retry params to the pub struct NodeConfig and feeding it through into pub async fn load_toml_config(.

Please let me know if that approach does / doesn't make sense.

Also do you know why I am getting those lint failures? I can't recreate them locally with the same commands. Fixing them crate by crate is slow because of this.

[Rjected]

Also do you know why I am getting those lint failures? I can't recreate them locally with the same commands. Fixing them crate by crate is slow because of this.

We're fixing some nightly clippy lints this morning, once that's merged it would probably be good to rebase

[Rjected]

changes are merged, I'll rebase my branch on main

[Rjected]

changes are merged, I'll rebase my branch on main

just rebased, so feel free to rebase on top of my updated branch

[sergerad]

@Rjected the code for retries and CLI args is in place. I moved the dns resolve fn into DNSNodeRecord scope also.

The --dns-retry-strategy interval=500,attempts=10 flag is an awkward approach. LMK what is preferred. E.G. perhaps --retry-count 10 and --retry-ms 500 instead

[Rjected]

great start!

E.G. perhaps --retry-count 10 and --retry-ms 500 instead

yeah I think this would be better, see comment

[sergerad]

Flags updated, parsing logic removed 👍

[sergerad]

@Rjected are we planning on adding DNSNodeRecord to the toml config file contents also? E.G. the PeersConfig struct uses NodeRecord:

pub struct Config {
// ...
    /// Configuration for the discovery service.
    pub peers: PeersConfig,
// ...
}
// ...
pub struct PeersConfig {
// ...
    pub trusted_nodes: HashSet<NodeRecord>,
// ...
    pub basic_nodes: HashSet<NodeRecord>,
// ...
}

EDIT: We might prefer to consolidate the DNSNodeRecord type into NodeRecord instead. I believe its possible if we update these getter fns (alongside a few other changes) to resolve the hostname to an IP if it hasn't been done yet:

impl NodeRecord {
// ...
    /// The TCP socket address of this node
    #[must_use]
    pub fn tcp_addr(&self) -> SocketAddr {
        SocketAddr::new(self.address, self.tcp_port)
    }

    /// The UDP socket address of this node
    #[must_use]
    pub fn udp_addr(&self) -> SocketAddr {
        SocketAddr::new(self.address, self.udp_port)
    }
}

[Rjected]

if we update these getter fns (alongside a few other changes) to resolve the hostname to an IP if it hasn't been done yet

While having less node record types is desirable, if we do this we need to make sure that we do not accept domain node records from discovery - these domain records should really only be used for trusted peers.

are we planning on adding DNSNodeRecord to the toml config file

That would make sense, although I can probably just do that in #8188

[Rjected]

lgtm, thanks!