Function create_root_node

src/vector_store.rs:44–150

(
    quantization_metric: &QuantizationMetric,
    storage_type: StorageType,
    dim: usize,
    prop_file: &RwLock<File>,
    version: VersionNumber,
    offset_counter: &HNSWIndexFileOffsetCounter

#[allow(clippy::too_many_arguments)]
pub fn create_root_node(
    quantization_metric: &QuantizationMetric,
    storage_type: StorageType,
    dim: usize,
    prop_file: &RwLock<File>,
    version: VersionNumber,
    offset_counter: &HNSWIndexFileOffsetCounter,
    cache: &HNSWIndexCache,
    values_range: (f32, f32),
    hnsw_params: &HNSWHyperParams,
    distance_metric: DistanceMetric,
    metadata_schema: Option<&MetadataSchema>,
) -> Result<SharedLatestNode, WaCustomError> {
    let vec = (0..dim)
        .map(|_| {
            let mut rng = rand::thread_rng();

            let random_number: f32 = rng.gen_range(values_range.0..values_range.1);
            random_number
        })
        .collect::<Vec<f32>>();
    let vec_hash = InternalId::from(u32::MAX);

    let vector_list = Arc::new(quantization_metric.quantize(&vec, storage_type, values_range)?);

    let mut prop_file_guard = prop_file.write().unwrap();
    let location = write_prop_value_to_file(&vec_hash, &vector_list, &mut prop_file_guard)?;

    let prop_value = Arc::new(NodePropValue {
        id: vec_hash,
        vec: vector_list,
        location,
    });

    let prop_metadata = match metadata_schema {
        Some(schema) => {
            let mbits = schema.base_dimensions();
            let metadata = Arc::new(Metadata { mag: 0.0, mbits });
            // A root node is similar to a base replica node. Hence
            // the replica_id and prop_value's id are same.
            let replica_id = vec_hash;
            let location =
                write_prop_metadata_to_file(replica_id, metadata.clone(), &mut prop_file_guard)?;
            Some(Arc::new(NodePropMetadata {
                replica_id: vec_hash,
                vec: metadata,
                location,
            }))
        }
        None => None,
    };

    drop(prop_file_guard);

    let file_id = offset_counter.file_id();

    let mut root = LazyItem::new(
        ProbNode::new(