Class MemoryBackend

vector/memoryBackend.js:81–307

}

export class MemoryBackend {
    constructor(options = {}) {
        this.name = options.name || 'default';
        this.dimension = options.dimension || null;
        this.metric = normalizeMetric(options.metric);
        this.normalizeVectors = options.normalize ?? (this.metric === 'cosine');
        this.size = 0;
        this.capacity = ensurePositiveInteger(options.capacity, 128);
        this.ids = new Array(this.capacity);
        this.metadata = new Array(this.capacity);
        this.vectors = null;
        this.idToIndex = new Map();
    }

    async init(options = {}) {
        if (options.dimension) {
            this.dimension = options.dimension;
        }
        if (!this.dimension || this.dimension <= 0) {
            throw new Error('Vector dimension must be provided.');
        }
        this.metric = normalizeMetric(options.metric || this.metric);
        this.normalizeVectors = options.normalize ?? this.normalizeVectors ?? (this.metric === 'cosine');
        if (!this.vectors || this.vectors.length !== this.capacity * this.dimension) {
            this.vectors = new Float32Array(this.capacity * this.dimension);
        }
    }

    prepareItems(items) {
        const prepared = [];
        for (const item of items) {
            if (!item) continue;
            const id = toId(item.id);
            const vector = prepareVector(item.vector, this.dimension, this.normalizeVectors);
            prepared.push({
                id,
                vector,
                metadata: item.metadata ?? null
            });
        }
        return prepared;
    }

    upsertPrepared(preparedItems) {
        for (const item of preparedItems) {
            const existingIndex = this.idToIndex.get(item.id);
            if (existingIndex !== undefined) {
                this._writeVector(existingIndex, item.vector);
                this.metadata[existingIndex] = item.metadata;
                continue;
            }

            const index = this.size;
            this._ensureCapacity(index + 1);
            this.ids[index] = item.id;
            this.metadata[index] = item.metadata;
            this.idToIndex.set(item.id, index);
            this._writeVector(index, item.vector);