@loopback/repository/dist/relations/relation.helpers.js

"use strict";
// Copyright IBM Corp. and LoopBack contributors 2019,2020. All Rights Reserved.
// Node module: @loopback/repository
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT
Object.defineProperty(exports, "__esModule", { value: true });
exports.isBsonType = exports.deduplicate = exports.reduceAsSingleItem = exports.reduceAsArray = exports.normalizeKey = exports.getKeyValue = exports.buildLookupMap = exports.flattenMapByKeys = exports.flattenTargetsOfOneToManyRelation = exports.flattenTargetsOfOneToOneRelation = exports.includeRelatedModels = exports.findByForeignKeys = void 0;
const tslib_1 = require("tslib");
const assert_1 = tslib_1.__importDefault(require("assert"));
const debug_1 = tslib_1.__importDefault(require("debug"));
const lodash_1 = tslib_1.__importStar(require("lodash"));
const __1 = require("..");
const debug = (0, debug_1.default)('loopback:repository:relation-helpers');
/**
 * Finds model instances that contain any of the provided foreign key values.
 *
 * @param targetRepository - The target repository where the related model instances are found
 * @param fkName - Name of the foreign key
 * @param fkValues - One value or array of values of the foreign key to be included
 * @param scope - Additional scope constraints
 * @param options - Options for the operations
 */
async function findByForeignKeys(targetRepository, fkName, fkValues, scope, options) {
    let value;
    scope = (0, lodash_1.cloneDeep)(scope);
    if (Array.isArray(fkValues)) {
        if (fkValues.length === 0)
            return [];
        value = fkValues.length === 1 ? fkValues[0] : { inq: fkValues };
    }
    else {
        value = fkValues;
    }
    let useScopeFilterGlobally = false;
    // If its an include from a through model, fkValues will be an array.
    // However, in this case we DO want to use the scope in the entire query, not
    // on a per-fk basis
    if (options) {
        useScopeFilterGlobally = options.isThroughModelInclude;
    }
    // If `scope.limit` is not defined, there is no reason to apply the scope to
    // each fk. This is to prevent unecessarily high database query counts.
    // See: https://github.com/loopbackio/loopback-next/issues/8074
    if (!(scope === null || scope === void 0 ? void 0 : scope.limit)) {
        useScopeFilterGlobally = true;
    }
    // This code is to keep backward compatibility.
    // See https://github.com/loopbackio/loopback-next/issues/6832 for more info.
    if (scope === null || scope === void 0 ? void 0 : scope.totalLimit) {
        scope.limit = scope.totalLimit;
        useScopeFilterGlobally = true;
        delete scope.totalLimit;
    }
    const isScopeSet = scope && !lodash_1.default.isEmpty(scope);
    if (isScopeSet && Array.isArray(fkValues) && !useScopeFilterGlobally) {
        // Since there is a scope, there could be a where filter, a limit, an order
        // and we should run the scope in multiple queries so we can respect the
        // scope filter params
        const findPromises = fkValues.map(fk => {
            const where = { [fkName]: fk };
            let localScope = (0, lodash_1.cloneDeep)(scope);
            // combine where clause to scope filter
            localScope = new __1.FilterBuilder(localScope).impose({ where }).filter;
            return targetRepository.find(localScope, options);
        });
        return Promise.all(findPromises).then(findResults => {
            //findResults is an array of arrays for each scope result, so we need to flatten it before returning it
            return lodash_1.default.flatten(findResults);
        });
    }
    else {
        const where = { [fkName]: value };
        if (isScopeSet) {
            // combine where clause to scope filter
            scope = new __1.FilterBuilder(scope).impose({ where }).filter;
        }
        else {
            scope = { where };
        }
        return targetRepository.find(scope, options);
    }
}
exports.findByForeignKeys = findByForeignKeys;
/**
 * Returns model instances that include related models that have a registered
 * resolver.
 *
 * @param targetRepository - The target repository where the model instances are found
 * @param entities - An array of entity instances or data
 * @param include -Inclusion filter
 * @param options - Options for the operations
 */
async function includeRelatedModels(targetRepository, entities, include, options) {
    entities = (0, lodash_1.cloneDeep)(entities);
    if (options === null || options === void 0 ? void 0 : options.polymorphicType) {
        include = include === null || include === void 0 ? void 0 : include.filter(inclusionFilter => {
            if (typeof inclusionFilter === 'string') {
                return true;
            }
            else {
                if (inclusionFilter.targetType === undefined ||
                    inclusionFilter.targetType === (options === null || options === void 0 ? void 0 : options.polymorphicType)) {
                    return true;
                }
            }
        });
    }
    else {
        include = (0, lodash_1.cloneDeep)(include);
    }
    const result = entities;
    if (!include)
        return result;
    const invalidInclusions = include.filter(inclusionFilter => !isInclusionAllowed(targetRepository, inclusionFilter));
    if (invalidInclusions.length) {
        const msg = 'Invalid "filter.include" entries: ' +
            invalidInclusions
                .map(inclusionFilter => JSON.stringify(inclusionFilter))
                .join('; ');
        const err = new Error(msg);
        Object.assign(err, {
            code: 'INVALID_INCLUSION_FILTER',
            statusCode: 400,
        });
        throw err;
    }
    const resolveTasks = include.map(async (inclusionFilter) => {
        const relationName = typeof inclusionFilter === 'string'
            ? inclusionFilter
            : inclusionFilter.relation;
        const resolver = targetRepository.inclusionResolvers.get(relationName);
        const targets = await resolver(entities, inclusionFilter, options);
        result.forEach((entity, ix) => {
            const src = entity;
            src[relationName] = targets[ix];
        });
    });
    await Promise.all(resolveTasks);
    return result;
}
exports.includeRelatedModels = includeRelatedModels;
/**
 * Checks if the resolver of the inclusion relation is registered
 * in the inclusionResolver of the target repository
 *
 * @param targetRepository - The target repository where the relations are registered
 * @param include - Inclusion filter
 */
function isInclusionAllowed(targetRepository, include) {
    const relationName = typeof include === 'string' ? include : include.relation;
    if (!relationName) {
        debug('isInclusionAllowed for %j? No: missing relation name', include);
        return false;
    }
    const allowed = targetRepository.inclusionResolvers.has(relationName);
    debug('isInclusionAllowed for %j (relation %s)? %s', include, allowed);
    return allowed;
}
/**
 * Returns an array of instances. The order of arrays is based on
 * the order of sourceIds
 *
 * @param sourceIds - One value or array of values of the target key
 * @param targetEntities - target entities that satisfy targetKey's value (ids).
 * @param targetKey - name of the target key
 *
 */
function flattenTargetsOfOneToOneRelation(sourceIds, targetEntities, targetKey) {
    const lookup = buildLookupMap(targetEntities, targetKey, reduceAsSingleItem);
    return flattenMapByKeys(sourceIds, lookup);
}
exports.flattenTargetsOfOneToOneRelation = flattenTargetsOfOneToOneRelation;
/**
 * Returns an array of instances. The order of arrays is based on
 * as a result of one to many relation. The order of arrays is based on
 * the order of sourceIds
 *
 * @param sourceIds - One value or array of values of the target key
 * @param targetEntities - target entities that satisfy targetKey's value (ids).
 * @param targetKey - name of the target key
 *
 */
function flattenTargetsOfOneToManyRelation(sourceIds, targetEntities, targetKey) {
    debug('flattenTargetsOfOneToManyRelation');
    debug('sourceIds', sourceIds);
    debug('sourceId types', sourceIds.map(i => typeof i));
    debug('targetEntities', targetEntities);
    debug('targetKey', targetKey);
    const lookup = buildLookupMap(targetEntities, targetKey, reduceAsArray);
    debug('lookup map', lookup);
    return flattenMapByKeys(sourceIds, lookup);
}
exports.flattenTargetsOfOneToManyRelation = flattenTargetsOfOneToManyRelation;
/**
 * Returns an array of instances from the target map. The order of arrays is based on
 * the order of sourceIds
 *
 * @param sourceIds - One value or array of values (of the target key)
 * @param targetMap - a map that matches sourceIds with instances
 */
function flattenMapByKeys(sourceIds, targetMap) {
    const result = new Array(sourceIds.length);
    // mongodb: use string as key of targetMap, and convert sourceId to strings
    // to make sure it gets the related instances.
    sourceIds.forEach((id, index) => {
        const key = normalizeKey(id);
        const target = targetMap.get(key);
        result[index] = target;
    });
    return result;
}
exports.flattenMapByKeys = flattenMapByKeys;
/**
 * Returns a map which maps key values(ids) to instances. The instances can be
 * grouped by different strategies.
 *
 * @param list - an array of instances
 * @param keyName - key name of the source
 * @param reducer - a strategy to reduce inputs to single item or array
 */
function buildLookupMap(list, keyName, reducer) {
    const lookup = new Map();
    for (const entity of list) {
        // get a correct key value
        const key = getKeyValue(entity, keyName);
        // these 3 steps are to set up the map, the map differs according to the reducer.
        const original = lookup.get(key);
        const reduced = reducer(original, entity);
        lookup.set(key, reduced);
    }
    return lookup;
}
exports.buildLookupMap = buildLookupMap;
/**
 * Returns value of a keyName. Aims to resolve ObjectId problem of Mongo.
 *
 * @param model - target model
 * @param keyName - target key that gets the value from
 */
function getKeyValue(model, keyName) {
    return normalizeKey(model[keyName]);
}
exports.getKeyValue = getKeyValue;
/**
 * Workaround for MongoDB, where the connector returns ObjectID
 * values even for properties configured with "type: string".
 *
 * @param rawKey
 */
function normalizeKey(rawKey) {
    if (isBsonType(rawKey)) {
        return rawKey.toString();
    }
    return rawKey;
}
exports.normalizeKey = normalizeKey;
/**
 * Returns an array of instances. For HasMany relation usage.
 *
 * @param acc
 * @param it
 */
function reduceAsArray(acc, it) {
    if (acc)
        acc.push(it);
    else
        acc = [it];
    return acc;
}
exports.reduceAsArray = reduceAsArray;
/**
 * Returns a single of an instance. For HasOne and BelongsTo relation usage.
 *
 * @param _acc
 * @param it
 */
function reduceAsSingleItem(_acc, it) {
    return it;
}
exports.reduceAsSingleItem = reduceAsSingleItem;
/**
 * Dedupe an array
 * @param input - an array of sourceIds
 * @returns an array with unique items
 */
function deduplicate(input) {
    const uniqArray = [];
    if (!input) {
        return uniqArray;
    }
    (0, assert_1.default)(Array.isArray(input), 'array argument is required');
    const comparableArray = input.map(item => normalizeKey(item));
    for (let i = 0, n = comparableArray.length; i < n; i++) {
        if (comparableArray.indexOf(comparableArray[i]) === i) {
            uniqArray.push(input[i]);
        }
    }
    return uniqArray;
}
exports.deduplicate = deduplicate;
/**
 * Checks if the value is BsonType (mongodb)
 * It uses a general way to check the type ,so that it can detect
 * different versions of bson that might be used in the code base.
 * Might need to update in the future.
 *
 * @param value
 */
function isBsonType(value) {
    if (typeof value !== 'object' || !value)
        return false;
    // bson@1.x stores _bsontype on ObjectID instance, bson@4.x on prototype
    return check(value) || check(value.constructor.prototype);
    function check(target) {
        return Object.prototype.hasOwnProperty.call(target, '_bsontype');
    }
}
exports.isBsonType = isBsonType;
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