shelving/db/store/ItemStore.js

Toolkit for using data in JavaScript.

import { RequiredError } from "../../error/RequiredError.js";
import { FetchStore } from "../../store/FetchStore.js";
import { getGetter } from "../../util/class.js";
import { NONE } from "../../util/constants.js";
import { getItem } from "../../util/item.js";
import { runSequence } from "../../util/sequence.js";
/** Store that stores a single item in a collection from a database provider. */
export class ItemStore extends FetchStore {
    provider;
    collection;
    id;
    /**
     * The required item data of this store.
     * @throws {RequiredError} if item doesn't exist (i.e. if `this.value` is `undefined`
     */
    get item() {
        const item = this.value;
        if (!item)
            throw new RequiredError(`Item does not exist in collection "${this.collection.name}"`, {
                store: this,
                provider: this.provider,
                collection: this.collection.name,
                id: this.id,
                caller: getGetter(this, "item"),
            });
        return item;
    }
    set item(data) {
        this.value = getItem(this.id, data);
    }
    constructor(collection, id, provider, memory) {
        const item = memory?.getTable(collection).getItem(id);
        super(item ?? NONE); // Use the current memory snapshot if available.
        if (memory)
            this.starter = store => runSequence(store.through(memory.getItemSequence(collection, id)));
        this.provider = provider;
        this.collection = collection;
        this.id = id;
    }
    // Override to get the item from the provider.
    _fetch(_signal) {
        return this.provider.getItem(this.collection, this.id);
    }
}