Enum MetadataEntry 

pub enum MetadataEntry {
    CatalogDdl {
        payload: Vec<u8>,
    },
    TopologyChange(TopologyChange),
    RoutingChange(RoutingChange),
    ClusterVersionBump {
        from: u16,
        to: u16,
    },
    DescriptorLeaseGrant(DescriptorLease),
    DescriptorLeaseRelease {
        node_id: u64,
        descriptor_ids: Vec<DescriptorId>,
    },
    DescriptorDrainStart {
        descriptor_id: DescriptorId,
        up_to_version: u64,
        expires_at: Hlc,
    },
    DescriptorDrainEnd {
        descriptor_id: DescriptorId,
    },
}

An entry in the replicated metadata log.

Every mutation to cluster-wide state — DDL, topology, routing, descriptor leases, cluster version bumps — is encoded as one of these variants, proposed against the metadata Raft group, and applied on every node by a crate::metadata_group::applier::MetadataApplier.

The CatalogDdl variant is the single wire shape for every DDL mutation. Its payload is an opaque, host-serialized nodedb::control::catalog_entry::CatalogEntry value — the nodedb-cluster crate is deliberately ignorant of the host’s per-DDL-object struct shapes. This keeps the cluster crate layering-clean and makes adding new DDL object types on the host side a zero-wire-change operation.

Variants

CatalogDdl

Single generic DDL entry carrying an opaque host-side payload. Produced by every pgwire DDL handler via nodedb::control::metadata_proposer::propose_catalog_entry.

Fields

payload: Vec<u8>

TopologyChange(TopologyChange)

RoutingChange(RoutingChange)

ClusterVersionBump

Fields

from: u16

to: u16

DescriptorLeaseGrant(DescriptorLease)

DescriptorLeaseRelease

Fields

node_id: u64

descriptor_ids: Vec<DescriptorId>

DescriptorDrainStart

Begin draining leases on a descriptor. While a drain entry is active, any acquire_descriptor_lease at version <= up_to_version must be rejected cluster-wide so the in-flight DDL that bumps the version can make progress.

expires_at is the HLC at which this drain entry is considered stale and ignored by is_draining checks on read. Acts as a TTL that prevents a crashed proposer from leaving an orphaned drain that blocks the cluster forever.

Fields

descriptor_id: DescriptorId

up_to_version: u64

expires_at: Hlc

DescriptorDrainEnd

End draining on a descriptor. Emitted explicitly on drain timeout so the cluster can make progress. On the happy path (successful Put* apply), the host-side applier clears drain implicitly — this variant is the escape hatch for the failure path.

Fields

descriptor_id: DescriptorId

Trait Implementations

impl Clone for MetadataEntry

fn clone(&self) -> MetadataEntry

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MetadataEntry

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for MetadataEntry

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<'__msgpack_de> FromMessagePack<'__msgpack_de> for MetadataEntry

fn read<R: Read<'__msgpack_de>>(reader: &mut R) -> Result<Self, Error>

where Self: Sized,

Reads the MessagePack representation of this value from the provided reader.

impl PartialEq for MetadataEntry

fn eq(&self, other: &MetadataEntry) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for MetadataEntry

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl ToMessagePack for MetadataEntry

fn write<W: Write>(&self, writer: &mut W) -> Result<(), Error>

Writes the MessagePack representation of this value into the provided writer.

impl Eq for MetadataEntry

impl StructuralPartialEq for MetadataEntry