Prevent crash on failed pgf payment

[grarco]

Describe your changes

Fixes a bug for which the ledger crashed in case of a failed PGF payment.

Indicate on which release or other PRs this topic is based on

Commit 3f979bf from base branch

Checklist before merging to draft

• I have added a changelog
• Git history is in acceptable state

[Fraccaman]

should we also do the same for cpgf? or does it already have the same behavior?

[grarco]

I think that the cPGF payment done in finalize_block is fine as it is. We are only propagating the error when crediting the tokens for the PGF account itself, which I think is fine since we can't really recover from that. For cpgf and stewards crediting we are instead already managing any possible errors

namada/apps/src/lib/node/ledger/shell/finalize_block.rs

Lines 839 to 917 in 3f979bf

	credit_tokens(
	&mut self.wl_storage,
	&staking_token,
	&pgf_address,
	pgf_inflation_amount,
	)?;
	tracing::info!(
	"Minting {} tokens for PGF rewards distribution into the PGF \
	account.",
	pgf_inflation_amount.to_string_native()
	);
	let mut pgf_fundings = pgf::get_payments(&self.wl_storage)?;
	// we want to pay first the oldest fundings
	pgf_fundings.sort_by(|a, b| a.id.cmp(&b.id));
	for funding in pgf_fundings {
	if credit_tokens(
	&mut self.wl_storage,
	&staking_token,
	&funding.detail.target,
	funding.detail.amount,
	)
	.is_ok()
	{
	tracing::info!(
	"Minted {} tokens for {} project.",
	funding.detail.amount.to_string_native(),
	&funding.detail.target,
	);
	} else {
	tracing::warn!(
	"Failed Minting {} tokens for {} project.",
	funding.detail.amount.to_string_native(),
	&funding.detail.target,
	);
	}
	}
	// Pgf steward inflation
	let stewards = pgf::get_stewards(&self.wl_storage)?;
	let pgf_steward_reward = match stewards.len() {
	0 => Dec::zero(),
	_ => pgf_steward_inflation
	.trunc_div(&Dec::from(stewards.len()))
	.unwrap_or_default(),
	};
	for steward in stewards {
	for (address, percentage) in steward.reward_distribution {
	let pgf_steward_reward = pgf_steward_reward
	.checked_mul(&percentage)
	.unwrap_or_default();
	let reward_amount = token::Amount::from(pgf_steward_reward);
	if credit_tokens(
	&mut self.wl_storage,
	&staking_token,
	&address,
	reward_amount,
	)
	.is_ok()
	{
	tracing::info!(
	"Minting {} tokens for steward {}.",
	reward_amount.to_string_native(),
	address,
	);
	} else {
	tracing::warn!(
	"Failed minting {} tokens for steward {}.",
	reward_amount.to_string_native(),
	address,
	);
	}
	}
	}