@nerdware/ddb-single-table/dist/esm/IOActions/typeChecking.js

A schema-based DynamoDB modeling tool, high-level API, and type-generator built to supercharge single-table designs!⚡

import { safeJsonStringify } from "@nerdware/ts-type-safety-utils";
import { hasDefinedProperty, isType, ItemInputError, getAttrErrID, stringifyNestedSchema, } from "../utils/index.js";
/**
 * This `IOAction` ensures item values conform with their `"type"` as defined in the schema.
 *
 * @throws {ItemInputError} If an attribute's value does not match the expected `"type"`.
 */
export const typeChecking = function (item, { schemaEntries, modelName, ...ctx }) {
    // Iterate over schemaEntries
    for (let i = 0; i < schemaEntries.length; i++) {
        const [attrName, attrConfig] = schemaEntries[i];
        // If the item does not have the attribute, or if its value is nullish, skip it
        if (!hasDefinedProperty(item, attrName))
            continue;
        // Check the type of its value (can't check unknown attributes if schema allows for them)
        if (!isType[attrConfig.type](item[attrName], attrConfig.oneOf ?? attrConfig.schema ?? [])) {
            // Throw error if there's a type mismatch
            throw new ItemInputError(`Invalid type of value provided for ${getAttrErrID(modelName, attrName, attrConfig)}.`
                + `\nExpected: ${attrConfig.type} `
                + (attrConfig.type === "enum"
                    ? `(oneOf: ${safeJsonStringify(attrConfig.oneOf)})`
                    : ["map", "array", "tuple"].includes(attrConfig.type)
                        ? `(schema: ${stringifyNestedSchema(attrConfig.schema)})`
                        : "")
                + `\nReceived: ${safeJsonStringify(item[attrName])}`);
        }
        // Run recursively on nested attributes
        if (attrConfig.schema) {
            this.recursivelyApplyIOAction(this.typeChecking, item[attrName], {
                parentItem: item,
                modelName,
                ...ctx,
                schema: attrConfig.schema, // <-- overwrites ctx.schema with the nested schema
            });
        }
    }
    return item;
};