aion-rs 0.22.0

//! What one read of the deployed contracts could — and could not — say about
//! declared task queues.
//!
//! A catalog can retain entries whose stored identity carries no decodable
//! contract at all: every package deployed before the `.v4` contract identity
//! reads that way. The handshake migration creates exactly that mixture —
//! old packages retained beside newly deployed `.v4` ones — so a bare set of
//! found queues is not an honest answer. Such a set reads as authoritative
//! while silently omitting whatever the undecodable entries declare, and a
//! caller that treats its absences as facts refuses dispatches nobody
//! contradicted.
//!
//! This type keeps both halves of the answer together, so a reader can tell
//! "no deployed contract declares this queue" apart from "this read could not
//! have seen it".

use std::collections::BTreeSet;

use aion_package::ContractIdentityError;

use super::load::LoadedWorkflow;

/// The queues one catalog read positively found, with the stored identities
/// that same read could not decode.
///
/// A positive find is a fact regardless of what the read missed. An ABSENCE is
/// only a fact when [`Self::covers_every_entry`] holds.
#[derive(Clone, Debug, Default, Eq, PartialEq)]
pub struct DeclaredQueues {
    declared: BTreeSet<String>,
    undecodable_identities: Vec<String>,
}

impl DeclaredQueues {
    /// Records one read: the queues found, and the stored identities that could
    /// not be decoded — empty exactly when the read covered every entry.
    #[must_use]
    pub fn new(declared: BTreeSet<String>, undecodable_identities: Vec<String>) -> Self {
        Self {
            declared,
            undecodable_identities,
        }
    }

    /// Whether a decoded contract declares `task_queue`.
    #[must_use]
    pub fn declares(&self, task_queue: &str) -> bool {
        self.declared.contains(task_queue)
    }

    /// Whether every retained entry decoded — the only condition under which
    /// this read's absences carry information.
    #[must_use]
    pub fn covers_every_entry(&self) -> bool {
        self.undecodable_identities.is_empty()
    }

    /// The stored identities this read could not decode, in catalog order.
    #[must_use]
    pub fn undecodable_identities(&self) -> &[String] {
        &self.undecodable_identities
    }

    /// Whether the read found no queue declaration at all. Such a catalog
    /// contradicts nothing, whether or not the read was complete.
    #[must_use]
    pub fn found_no_declaration(&self) -> bool {
        self.declared.is_empty()
    }

    /// Every queue this read found.
    #[must_use]
    pub fn declared(&self) -> &BTreeSet<String> {
        &self.declared
    }

    /// Reads the declarations out of retained catalog entries.
    ///
    /// This is the site that OBSERVES an entry it cannot decode, so this is the
    /// site that says so: an undecodable entry is recorded by its stored
    /// identity and reported at WARN, naming what must be re-deployed. It is
    /// never skipped in silence — a skipped entry turns into a confident,
    /// terminal refusal three seams downstream.
    pub(crate) fn read<'entries>(
        entries: impl IntoIterator<Item = &'entries LoadedWorkflow>,
    ) -> Self {
        let mut declared = BTreeSet::new();
        let mut undecodable_identities = Vec::new();
        for workflow in entries {
            match workflow.contract() {
                Ok(contract) => {
                    for worker in &contract.workers {
                        declared.insert(worker.task_queue.clone());
                    }
                }
                Err(ContractIdentityError::RedeployRequired { stored_version }) => {
                    undecodable_identities.push(stored_version);
                }
            }
        }
        if !undecodable_identities.is_empty() {
            tracing::warn!(
                undecodable_identities = %undecodable_identities.join(", "),
                declared_queues = declared.len(),
                "catalog entries carry no decodable contract; their task queues are unknowable \
                 and no queue can be reported undeclared until they are re-deployed under `.v4`"
            );
        }
        Self {
            declared,
            undecodable_identities,
        }
    }
}

#[cfg(test)]
#[path = "declared_queues_tests.rs"]
mod declared_queues_tests;