Struct Manifest 

pub struct Manifest {
    pub format: String,
    pub format_version: u32,
    pub capabilities: Vec<String>,
    pub schemas: Vec<SchemaTemplateRef>,
    pub compression: String,
    pub blob_ordering: Option<String>,
    pub directory: DirectoryRef,
    pub packs: Vec<PackRef>,
    pub metadata: Metadata,
}

The packed-format manifest.json — the only mutable object per dataset.

Folds the metadata, directory pointer and pack table into one tiny JSON so a cold reader needs exactly one manifest + one directory + N pack-range fetches (no separate header or metadata object).

Fields

format: String

Always PACKED_FORMAT ("stt-packed").

format_version: u32

Manifest schema version.

capabilities: Vec<String>

Required-to-understand feature declarations (spec §3.1). Each entry names a feature the writer used that RE-TYPES existing tile columns (registry: KNOWN_CAPABILITIES); a reader MUST refuse a dataset declaring a capability it does not implement. Empty when no such feature was used — omitted from the JSON so pre-capabilities builds stay byte-identical. Additive columns never need a capability.

schemas: Vec<SchemaTemplateRef>

formatVersion ≥ 2: the dataset’s Arrow schema templates, embedded directly in the manifest (no extra object class — every session already fetches the manifest). Each entry is a layer schema’s IPC prefix, referenced from v2 layer frames by blake3-128 hash. Sorted by hash and deduped (byte-reproducible manifests); a reader validates blake3(data) == hash for every entry at open, so a corrupt manifest fails loudly, dataset-level, before any tile fetch. Absent/empty on formatVersion-1 manifests (the key is omitted).

compression: String

Blob compression codec (always "zstd", per-blob, no shared dict).

blob_ordering: Option<String>

The concrete blob byte-ordering the writer resolved and laid down (spatial | time-major | hilbert3 | morton3) — see crate::curve::BlobOrdering. Additive/optional: pre-2026-07 archives omit it (a reader infers the order from the (pack_id, offset) layout). Never auto/measured — those resolve to a concrete order at build. Omitted from the JSON when None so pre-field builds stay byte-identical.

directory: DirectoryRef

Pointer to the encoded directory object.

packs: Vec<PackRef>

Pack table. Index == pack_id.

metadata: Metadata

The full crate::metadata::Metadata JSON, verbatim.

Implementations

impl Manifest

pub fn from_json_bytes(bytes: &[u8]) -> Result<Self>

Parse a manifest from its JSON bytes.

pub fn to_json_bytes(&self) -> Result<Vec<u8>>

Serialise the manifest to pretty JSON bytes.

Trait Implementations

impl Clone for Manifest

fn clone(&self) -> Manifest

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Manifest

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Manifest

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Manifest

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

where __S: Serializer,

Serialize this value into the given Serde serializer.