Verify a chunked dataset

Start with deterministic chunks

Weft's actual Rust package is weave-weft; import it as weave_weft. Use a path dependency to models/weft in an authorized checkout. This function builds a manifest and signs its exact canonical signing payload with a caller-supplied Ed25519 signing key.

[dependencies]
weave-weft = { path = "../weave/models/weft" }
ed25519-dalek = "2"

use ed25519_dalek::{Signer, SigningKey};
use weave_weft::{
    chunk::{chunk_bytes, ChunkConfig},
    manifest::{ArtifactMetadata, ManifestProducer, WeftManifest,
        WEFT_MANIFEST_SCHEMA, WEFT_MANIFEST_VERSION},
    tree::MerkleTree,
};

fn signed_manifest(
    bytes: &[u8],
    config: ChunkConfig,
    producer_did: String,
    artifact: ArtifactMetadata,
    key: &SigningKey,
) -> weave_weft::Result<WeftManifest> {
    let chunks = chunk_bytes(bytes, config)?;
    let root = MerkleTree::from_leaves(chunks.iter().map(|c| c.id).collect())?.root();
    let mut manifest = WeftManifest {
        schema: WEFT_MANIFEST_SCHEMA.to_string(),
        version: WEFT_MANIFEST_VERSION,
        root,
        chunk_size: config.chunk_size() as u64,
        chunk_count: chunks.len() as u64,
        total_len: bytes.len() as u64,
        chunks,
        parity: None,
        producer: ManifestProducer {
            did: producer_did,
            signing_key_id: None,
            signature: Vec::new(),
        },
        artifact,
    };
    manifest.producer.signature = key.sign(&manifest.signing_payload()?).to_bytes().to_vec();
    manifest.validate()?;
    Ok(manifest)
}

The unsigned draft exists only in memory: it is signed before validation or publication. This function is source-checked; it was not compiled or executed in this docs pass.

Verify the producer and payload

The caller is responsible for binding producer_did to the supplied key through a trusted identity resolver. Structural validate() checks do not establish that binding. A consumer verifies the producer signature, manifest version and chunk/root integrity against the expected artifact. Use the manifest and fetch references for the exact inputs and error types.

Persist, publish and retrieve

LocalWeftStore offers a real local store; the dht feature enables the live DHT adapter. Read local storage, discovery and live adapter before choosing transport. Reader/chunk APIs can avoid a single contiguous input buffer, but the local store retains chunks in memory. They do not establish constant-memory processing.

Chain anchoring is a separate operation

The optional MARS and Sigil metadata fields are informational until a real accepted transaction or registry receipt is linked and verified. This example performs no chain transaction and supplies no no-op anchor fallback. Follow the configured network's Sigil evidence flow and MARS docs for that boundary.