feat: add countdown log till genesis

[MuhtasimTanmoy]

What was wrong?

#886

How was it fixed?

#1104

To-Do

Review

[MuhtasimTanmoy]

[KolbyML]

Isn't this expect() comment misleading?, I think we should avoid expect here, handle the exception intentionally and safely

[MuhtasimTanmoy]

Referenced from here.

ream/crates/common/network_spec/src/networks/lean.rs

Line 84 in d131153

.expect("System time is before UNIX epoch")

[KolbyML]

Yeah I will be removing those in a PR I am working on

[MuhtasimTanmoy]

  let now = SystemTime::now()
                      .duration_since(UNIX_EPOCH)
                      .unwrap_or(Duration::MAX)// remaining <= 0 will be true if error
                      .as_secs();
        let remaining = lean_network_spec().genesis_time - now;

        if remaining <= 0 {
            info!("Genesis reached! Starting services...");
            break;
        }

Does this look ok? Or should safely log error for that specific case?

[KolbyML]

let remaining = lean_network_spec().genesis_time.saturating_sub(now);

You should do a saturating sub then to avoid underflows

[MuhtasimTanmoy]

let now = SystemTime::now()
                      .duration_since(UNIX_EPOCH)
                      .unwrap_or(Duration::MAX)
                      .as_secs();
let remaining = lean_network_spec().genesis_time.saturating_sub(now);

if remaining == 0 {
    info!("Genesis reached! Starting services...");
    break;
}

If this looks okay, then will update the PR.

[KolbyML]

Remove the // remaining <= 0 will be true if error

also if now == Duration::MAX we should not print anything and just immediately break

So maybe do

 let now = match SystemTime::now()
                      .duration_since(UNIX_EPOCH) {
                           Ok(now) => now.as_secs(),
                           // The chain is already past genesis, we don't need a countdown
                           Err(_) => break,
                      };
                      
let remaining = lean_network_spec().genesis_time.saturating_sub(now);

if remaining == 0 {
    info!("Genesis reached! Starting services...");
    break;
}

^ so do something like this

[KolbyML]

I didn't suggest that looking at the full context, so you might need to make further modifications

[MuhtasimTanmoy]

Thanks.

[MuhtasimTanmoy]

I tested.

[KolbyML]

Suggested change

	let now = match SystemTime::now().duration_since(UNIX_EPOCH) {
	Ok(now) => now.as_secs(),
	// The chain is already past genesis, we don't need a countdown
	Err(_) => break,
	};
	let remaining = lean_network_spec().genesis_time.saturating_sub(now);
	if remaining == 0 {
	info!("Genesis reached! Starting services...");
	break;
	}
	let now = SystemTime::now()
	.duration_since(UNIX_EPOCH)
	.unwrap_or(Duration::MAX)
	.as_secs();
	let genesis = lean_network_spec().genesis_time;
	if now >= genesis {
	if now <= genesis + 2 {
	info!("Genesis reached! Starting services...");
	}
	break;
	}

After reading the code a bit more, could you do this ^