mkit-server 0.5.0

//! Launch-only synchronous checks. No hold, timer, or durable continuation.

use crate::ServerError;
use crate::hooks::InspectVerdict;
use crate::op::Operation;
use crate::rt::{BoxFuture, MaybeSend, MaybeSync};
use mkit_rpc::hooks::{InspectObject, InspectRetrieval};

/// The launch ceiling and default inspected-set bound.
pub const MAX_OBJECTS: usize = 10_000;
/// The launch inspector bound.
pub const MAX_INSPECTORS: usize = 4;
/// Indexed verification and pack-count preflight share this allocation.
pub const VERIFY_CALLS: u32 = 300;
/// Existing ancestry, resulting-pair walk, hooks, and other-stage allocations.
pub const ADVANCE_CALLS: u32 = VERIFY_CALLS + 256 + 256 + 4 + 144;
const _: () = assert!(ADVANCE_CALLS <= 1_000);

/// Configured inspection phase.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum InspectorPhase {
    /// Before apply.
    Sync,
    /// Full-profile follow-up, refused at launch.
    Async,
}
/// Inspector availability policy.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum OnUnavailable {
    /// Fail without committing or recording replay.
    FailClosed,
    /// Full-profile follow-up, refused at launch.
    Publish,
}
/// Metadata-only inspection. Enumeration belongs to the server.
pub trait ContentInspector: MaybeSend + MaybeSync {
    /// Stable, unique deployment identity.
    fn id(&self) -> &str;
    /// Launch supports synchronous checks only.
    fn phase(&self) -> InspectorPhase {
        InspectorPhase::Sync
    }
    /// Launch supports fail-closed availability only.
    fn on_unavailable(&self) -> OnUnavailable {
        OnUnavailable::FailClosed
    }
    /// Bound capability validity to this inspector's actual hook timeout.
    fn retrieval_timeout(&self) -> core::time::Duration {
        crate::hooks::DEFAULT_TIMEOUT
    }
    /// Inspect with optional private retrieval metadata. In-process inspectors
    /// can use this seam without sending object bytes in the metadata request.
    fn inspect_with_retrieval<'a>(
        &'a self,
        op: &'a Operation,
        id: &'a str,
        objects: &'a [InspectObject],
        retrieval: Option<InspectRetrieval>,
    ) -> BoxFuture<'a, Result<InspectVerdict, ServerError>> {
        let _ = retrieval;
        self.inspect(op, id, objects)
    }
    /// Inspect exactly this assigned batch; the logical id survives retries.
    fn inspect<'a>(
        &'a self,
        op: &'a Operation,
        id: &'a str,
        objects: &'a [InspectObject],
    ) -> BoxFuture<'a, Result<InspectVerdict, ServerError>>;
}

pub(super) struct Immediate;
impl super::clearance::PublicationPolicy for Immediate {
    fn prepare<'a>(
        &'a self,
        _: &'a Operation,
        pair: &'a crate::store::publication::Pair,
    ) -> BoxFuture<'a, Result<crate::store::publication::Advance, ServerError>> {
        Box::pin(async move {
            Ok(super::clearance::immediate(
                pair.clone(),
                [0; 32],
                Vec::new(),
            ))
        })
    }
    fn pack_available(&self, _: &crate::repo::RepoId, _: &mkit_core::hash::Hash) -> bool {
        true
    }
}

impl<B: crate::store::MultipartBlobStore, N: crate::NamespaceStore, H: super::HookSet>
    super::Pipeline<B, N, H>
{
    pub(super) async fn inspect_advance(
        &self,
        op: &Operation,
        pair: &crate::store::publication::Pair,
        objects: Vec<crate::indexed::inspection::InspectObject>,
        assignment: Option<&crate::scanner_retrieval::Assignment>,
    ) -> Result<(), ServerError> {
        use mkit_rpc::hooks::InspectObjectKind as K;
        let objects: Vec<_> = objects
            .into_iter()
            .map(|object| InspectObject {
                id: Some(object.id.to_vec()),
                size: Some(object.size),
                kind: Some(
                    match object.kind {
                        crate::indexed::inspection::Kind::Blob => K::INSPECT_OBJECT_KIND_BLOB,
                        crate::indexed::inspection::Kind::ChunkedFile => {
                            K::INSPECT_OBJECT_KIND_CHUNKED_FILE
                        }
                    }
                    .into(),
                ),
                ..Default::default()
            })
            .collect();
        let mut rejection = None;
        let mut unavailable = None;
        for inspector in &self.inspectors {
            // The id binds the inspector, signed logical advance, phase and
            // immutable batch. A changed resulting pair or metadata is a new
            // logical batch; signing nonces do not change this identity.
            let bytes = serde_json::to_vec(&(
                inspector.id(),
                op.repo.namespace.as_str(),
                op.repo.name.as_str(),
                op.auth.as_ref().map(|a| a.fingerprint),
                pair,
                "PRE_RECEIVE",
                &objects,
            ))
            .map_err(|_| ServerError::unavailable("inspection metadata unavailable"))?;
            let id = mkit_core::hash::to_hex(&mkit_core::hash::hash(&bytes));
            let retrieval = match (&self.cfg.scanner_retrieval, assignment) {
                (Some(config), Some(assignment)) => {
                    let super::AuthMode::AuthV2(auth) = &self.cfg.auth else {
                        return Err(ServerError::unavailable("retrieval unavailable"));
                    };
                    config
                        .mint(
                            auth.audience(),
                            &id,
                            assignment,
                            inspector.retrieval_timeout(),
                            u64::try_from(self.clock.now_ms()).unwrap_or(0),
                        )
                        .map(Some)
                }
                (Some(_), None) => Err(ServerError::unavailable("retrieval unavailable")),
                (None, _) => Ok(None),
            };
            let verdict = match retrieval {
                Ok(retrieval) => {
                    inspector
                        .inspect_with_retrieval(op, &id, &objects, retrieval)
                        .await
                }
                Err(error) => Err(error),
            };
            let result = match &verdict {
                Ok(InspectVerdict::Pass) => "pass",
                Ok(InspectVerdict::Reject(_)) => "reject",
                Err(_) => "unavailable",
            };
            self.metrics.incr(
                crate::telemetry::METRIC_INSPECTION_CALLS,
                &[("result", result)],
                1,
            );
            match verdict {
                Ok(InspectVerdict::Pass) => {}
                Ok(InspectVerdict::Reject(message)) => rejection = Some(message),
                Err(_) => {
                    unavailable = Some(ServerError::unavailable("inspection unavailable; retry"));
                }
            }
        }
        if let Some(message) = rejection {
            return Err(ServerError::permission_denied(message));
        }
        if let Some(error) = unavailable {
            return Err(error);
        }
        Ok(())
    }
}

#[cfg(test)]
mod tests {
    #[test]
    fn launch_advance_allocations_fit_the_repository_contract() {
        // Verification has 300 calls. Pair closure, frame enumeration and
        // dependency visibility share another 256 calls.
        // Even seven independently rounded packs require <=16 pages for
        // <=10,000 total entries at the Worker's 1,000-row page ceiling.
        let frame_pages = super::MAX_OBJECTS.div_ceil(1_000) + 6;
        assert_eq!(frame_pages, 16);
        // Two batched reads bind the accepted verification-job snapshots
        // before and after enumeration, including all seven packs per read.
        let enumeration_calls = frame_pages + 2;
        assert_eq!(enumeration_calls, 18);
        assert!(enumeration_calls < 256);
        assert_eq!(super::MAX_INSPECTORS, 4);
        assert_eq!(super::ADVANCE_CALLS, 960);
        const {
            assert!(super::ADVANCE_CALLS <= 1_000);
        }
    }
}