loopback-datasource-juggler/lib/utils.js

619 lines
17 KiB
JavaScript

// Copyright IBM Corp. 2012,2016. All Rights Reserved.
// Node module: loopback-datasource-juggler
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT
'use strict';
exports.safeRequire = safeRequire;
exports.fieldsToArray = fieldsToArray;
exports.selectFields = selectFields;
exports.removeUndefined = removeUndefined;
exports.parseSettings = parseSettings;
exports.mergeSettings = exports.deepMerge = mergeSettings;
exports.isPlainObject = isPlainObject;
exports.defineCachedRelations = defineCachedRelations;
exports.sortObjectsByIds = sortObjectsByIds;
exports.setScopeValuesFromWhere = setScopeValuesFromWhere;
exports.mergeQuery = mergeQuery;
exports.mergeIncludes = mergeIncludes;
exports.createPromiseCallback = createPromiseCallback;
exports.uniq = uniq;
exports.toRegExp = toRegExp;
exports.hasRegExpFlags = hasRegExpFlags;
exports.idEquals = idEquals;
exports.findIndexOf = findIndexOf;
exports.collectTargetIds = collectTargetIds;
exports.idName = idName;
var g = require('strong-globalize')();
var traverse = require('traverse');
var assert = require('assert');
var Promise = require('bluebird');
function safeRequire(module) {
try {
return require(module);
} catch (e) {
g.log('Run "{{npm install loopback-datasource-juggler}} %s" command ',
'to use {{loopback-datasource-juggler}} using %s database engine',
module, module);
process.exit(1);
}
}
/*
* Extracting fixed property values for the scope from the where clause into
* the data object
*
* @param {Object} The data object
* @param {Object} The where clause
*/
function setScopeValuesFromWhere(data, where, targetModel) {
for (var i in where) {
if (i === 'and') {
// Find fixed property values from each subclauses
for (var w = 0, n = where[i].length; w < n; w++) {
setScopeValuesFromWhere(data, where[i][w], targetModel);
}
continue;
}
var prop = targetModel.definition.properties[i];
if (prop) {
var val = where[i];
if (typeof val !== 'object' || val instanceof prop.type ||
prop.type.name === 'ObjectID') { // MongoDB key
// Only pick the {propertyName: propertyValue}
data[i] = where[i];
}
}
}
}
/**
* Merge include options of default scope with runtime include option.
* exhibits the _.extend behaviour. Property value of source overrides
* property value of destination if property name collision occurs
* @param {String|Array|Object} destination The default value of `include` option
* @param {String|Array|Object} source The runtime value of `include` option
* @returns {Object}
*/
function mergeIncludes(destination, source) {
var destArray = convertToArray(destination);
var sourceArray = convertToArray(source);
if (destArray.length === 0) {
return sourceArray;
}
if (sourceArray.length === 0) {
return destArray;
}
var relationNames = [];
var resultArray = [];
for (var j in sourceArray) {
var sourceEntry = sourceArray[j];
var sourceEntryRelationName = (typeof (sourceEntry.rel || sourceEntry.relation) === 'string') ?
sourceEntry.relation : Object.keys(sourceEntry)[0];
relationNames.push(sourceEntryRelationName);
resultArray.push(sourceEntry);
}
for (var i in destArray) {
var destEntry = destArray[i];
var destEntryRelationName = (typeof (destEntry.rel || destEntry.relation) === 'string') ?
destEntry.relation : Object.keys(destEntry)[0];
if (relationNames.indexOf(destEntryRelationName) === -1) {
resultArray.push(destEntry);
}
}
return resultArray;
}
/**
* Converts input parameter into array of objects which wraps the value.
* "someValue" is converted to [{"someValue":true}]
* ["someValue"] is converted to [{"someValue":true}]
* {"someValue":true} is converted to [{"someValue":true}]
* @param {String|Array|Object} param - Input parameter to be converted
* @returns {Array}
*/
function convertToArray(include) {
if (typeof include === 'string') {
const obj = {};
obj[include] = true;
return [obj];
} else if (isPlainObject(include)) {
// if include is of the form - {relation:'',scope:''}
if (include.rel || include.relation) {
return [include];
}
// Build an array of key/value pairs
var newInclude = [];
for (var key in include) {
const obj = {};
obj[key] = include[key];
newInclude.push(obj);
}
return newInclude;
} else if (Array.isArray(include)) {
var normalized = [];
for (var i in include) {
var includeEntry = include[i];
if (typeof includeEntry === 'string') {
const obj = {};
obj[includeEntry] = true;
normalized.push(obj);
} else {
normalized.push(includeEntry);
}
}
return normalized;
}
return [];
}
/*!
* Merge query parameters
* @param {Object} base The base object to contain the merged results
* @param {Object} update The object containing updates to be merged
* @param {Object} spec Optionally specifies parameters to exclude (set to false)
* @returns {*|Object} The base object
* @private
*/
function mergeQuery(base, update, spec) {
if (!update) {
return;
}
spec = spec || {};
base = base || {};
if (update.where && Object.keys(update.where).length > 0) {
if (base.where && Object.keys(base.where).length > 0) {
base.where = {and: [base.where, update.where]};
} else {
base.where = update.where;
}
}
// Merge inclusion
if (spec.include !== false && update.include) {
if (!base.include) {
base.include = update.include;
} else {
if (spec.nestedInclude === true) {
// specify nestedInclude=true to force nesting of inclusions on scoped
// queries. e.g. In physician.patients.getAsync({include: 'address'}),
// inclusion should be on patient model, not on physician model.
var saved = base.include;
base.include = {};
base.include[update.include] = saved;
} else {
// default behaviour of inclusion merge - merge inclusions at the same
// level. - https://github.com/strongloop/loopback-datasource-juggler/pull/569#issuecomment-95310874
base.include = mergeIncludes(base.include, update.include);
}
}
}
if (spec.collect !== false && update.collect) {
base.collect = update.collect;
}
// Overwrite fields
if (spec.fields !== false && update.fields !== undefined) {
base.fields = update.fields;
} else if (update.fields !== undefined) {
base.fields = [].concat(base.fields).concat(update.fields);
}
// set order
if ((!base.order || spec.order === false) && update.order) {
base.order = update.order;
}
// overwrite pagination
if (spec.limit !== false && update.limit !== undefined) {
base.limit = update.limit;
}
var skip = spec.skip !== false && spec.offset !== false;
if (skip && update.skip !== undefined) {
base.skip = update.skip;
}
if (skip && update.offset !== undefined) {
base.offset = update.offset;
}
return base;
}
/**
* Normalize fields to an array of included properties
* @param {String|String[]|Object} fields Fields filter
* @param {String[]} properties Property names
* @param {Boolean} excludeUnknown To exclude fields that are unknown properties
* @returns {String[]} An array of included property names
*/
function fieldsToArray(fields, properties, excludeUnknown) {
if (!fields) return;
// include all properties by default
var result = properties;
var i, n;
if (typeof fields === 'string') {
result = [fields];
} else if (Array.isArray(fields) && fields.length > 0) {
// No empty array, including all the fields
result = fields;
} else if ('object' === typeof fields) {
// { field1: boolean, field2: boolean ... }
var included = [];
var excluded = [];
var keys = Object.keys(fields);
if (!keys.length) return;
for (i = 0, n = keys.length; i < n; i++) {
var k = keys[i];
if (fields[k]) {
included.push(k);
} else if ((k in fields) && !fields[k]) {
excluded.push(k);
}
}
if (included.length > 0) {
result = included;
} else if (excluded.length > 0) {
for (i = 0, n = excluded.length; i < n; i++) {
var index = result.indexOf(excluded[i]);
if (index !== -1) result.splice(index, 1); // only when existing field excluded
}
}
}
var fieldArray = [];
if (excludeUnknown) {
for (i = 0, n = result.length; i < n; i++) {
if (properties.indexOf(result[i]) !== -1) {
fieldArray.push(result[i]);
}
}
} else {
fieldArray = result;
}
return fieldArray;
}
function selectFields(fields) {
// map function
return function(obj) {
var result = {};
var key;
for (var i = 0; i < fields.length; i++) {
key = fields[i];
result[key] = obj[key];
}
return result;
};
}
/**
* Remove undefined values from the queury object
* @param query
* @param handleUndefined {String} either "nullify", "throw" or "ignore" (default: "ignore")
* @returns {exports.map|*}
*/
function removeUndefined(query, handleUndefined) {
if (typeof query !== 'object' || query === null) {
return query;
}
// WARNING: [rfeng] Use map() will cause mongodb to produce invalid BSON
// as traverse doesn't transform the ObjectId correctly
return traverse(query).forEach(function(x) {
if (x === undefined) {
switch (handleUndefined) {
case 'nullify':
this.update(null);
break;
case 'throw':
throw new Error(g.f('Unexpected `undefined` in query'));
break;
case 'ignore':
default:
this.remove();
}
}
if (!Array.isArray(x) && (typeof x === 'object' && x !== null &&
x.constructor !== Object)) {
// This object is not a plain object
this.update(x, true); // Stop navigating into this object
return x;
}
return x;
});
}
var url = require('url');
var qs = require('qs');
/**
* Parse a URL into a settings object
* @param {String} urlStr The URL for connector settings
* @returns {Object} The settings object
*/
function parseSettings(urlStr) {
if (!urlStr) {
return {};
}
var uri = url.parse(urlStr, false);
var settings = {};
settings.connector = uri.protocol && uri.protocol.split(':')[0]; // Remove the trailing :
settings.host = settings.hostname = uri.hostname;
settings.port = uri.port && Number(uri.port); // port is a string
settings.user = settings.username = uri.auth && uri.auth.split(':')[0]; // <username>:<password>
settings.password = uri.auth && uri.auth.split(':')[1];
settings.database = uri.pathname && uri.pathname.split('/')[1]; // remove the leading /
settings.url = urlStr;
if (uri.query) {
var params = qs.parse(uri.query);
for (var p in params) {
settings[p] = params[p];
}
}
return settings;
}
/**
* Merge model settings
*
* Folked from https://github.com/nrf110/deepmerge/blob/master/index.js
*
* The original function tries to merge array items if they are objects
*
* @param {Object} target The target settings object
* @param {Object} src The source settings object
* @returns {Object} The merged settings object
*/
function mergeSettings(target, src) {
var array = Array.isArray(src);
var dst = array && [] || {};
if (array) {
target = target || [];
// Add items from target into dst
dst = dst.concat(target);
// Add non-existent items from source into dst
src.forEach(function(e) {
if (dst.indexOf(e) === -1) {
dst.push(e);
}
});
} else {
if (target != null && typeof target === 'object') {
// Add properties from target to dst
Object.keys(target).forEach(function(key) {
dst[key] = target[key];
});
}
if (src != null && typeof src === 'object') {
// Source is an object
Object.keys(src).forEach(function(key) {
var srcValue = src[key];
if (srcValue == null || typeof srcValue !== 'object') {
// The source item value is null, undefined or not an object
dst[key] = srcValue;
} else {
// The source item value is an object
if (target == null || typeof target !== 'object' ||
target[key] == null) {
// If target is not an object or target item value
dst[key] = srcValue;
} else {
dst[key] = mergeSettings(target[key], src[key]);
}
}
});
}
}
return dst;
}
/**
* Define an non-enumerable __cachedRelations property
* @param {Object} obj The obj to receive the __cachedRelations
*/
function defineCachedRelations(obj) {
if (!obj.__cachedRelations) {
Object.defineProperty(obj, '__cachedRelations', {
writable: true,
enumerable: false,
configurable: true,
value: {},
});
}
}
/**
* Check if the argument is plain object
* @param {*) obj The obj value
* @returns {boolean}
*/
function isPlainObject(obj) {
return (typeof obj === 'object') && (obj !== null) &&
(obj.constructor === Object);
}
function sortObjectsByIds(idName, ids, objects, strict) {
ids = ids.map(function(id) {
return (typeof id === 'object') ? String(id) : id;
});
var indexOf = function(x) {
var isObj = (typeof x[idName] === 'object'); // ObjectID
var id = isObj ? String(x[idName]) : x[idName];
return ids.indexOf(id);
};
var heading = [];
var tailing = [];
objects.forEach(function(x) {
if (typeof x === 'object') {
var idx = indexOf(x);
if (strict && idx === -1) return;
idx === -1 ? tailing.push(x) : heading.push(x);
}
});
heading.sort(function(x, y) {
var a = indexOf(x);
var b = indexOf(y);
if (a === -1 || b === -1) return 1; // last
if (a === b) return 0;
if (a > b) return 1;
if (a < b) return -1;
});
return heading.concat(tailing);
};
function createPromiseCallback() {
var cb;
var promise = new Promise(function(resolve, reject) {
cb = function(err, data) {
if (err) return reject(err);
return resolve(data);
};
});
cb.promise = promise;
return cb;
}
/**
* Dedupe an array
* @param {Array} an array
* @returns {Array} an array with unique items
*/
function uniq(a) {
var uniqArray = [];
if (!a) {
return uniqArray;
}
assert(Array.isArray(a), 'array argument is required');
for (var i = 0, n = a.length; i < n; i++) {
if (a.indexOf(a[i]) === i) {
uniqArray.push(a[i]);
}
}
return uniqArray;
}
/**
* Converts a string, regex literal, or a RegExp object to a RegExp object.
* @param {String|Object} The string, regex literal, or RegExp object to convert
* @returns {Object} A RegExp object
*/
function toRegExp(regex) {
var isString = typeof regex === 'string';
var isRegExp = regex instanceof RegExp;
if (!(isString || isRegExp))
return new Error(g.f('Invalid argument, must be a string, {{regex}} literal, or ' +
'{{RegExp}} object'));
if (isRegExp)
return regex;
if (!hasRegExpFlags(regex))
return new RegExp(regex);
// only accept i, g, or m as valid regex flags
var flags = regex.split('/').pop().split('');
var validFlags = ['i', 'g', 'm'];
var invalidFlags = [];
flags.forEach(function(flag) {
if (validFlags.indexOf(flag) === -1)
invalidFlags.push(flag);
});
var hasInvalidFlags = invalidFlags.length > 0;
if (hasInvalidFlags)
return new Error(g.f('Invalid {{regex}} flags: %s', invalidFlags));
// strip regex delimiter forward slashes
var expression = regex.substr(1, regex.lastIndexOf('/') - 1);
return new RegExp(expression, flags.join(''));
}
function hasRegExpFlags(regex) {
return regex instanceof RegExp ?
regex.toString().split('/').pop() :
!!regex.match(/.*\/.+$/);
}
// Compare two id values to decide if updateAttributes is trying to change
// the id value for a given instance
function idEquals(id1, id2) {
if (id1 === id2) {
return true;
}
// Allows number/string conversions
if ((typeof id1 === 'number' && typeof id2 === 'string') ||
(typeof id1 === 'string' && typeof id2 === 'number')) {
return id1 == id2;
}
// For complex id types such as MongoDB ObjectID
id1 = JSON.stringify(id1);
id2 = JSON.stringify(id2);
if (id1 === id2) {
return true;
}
return false;
}
// Defaults to native Array.prototype.indexOf when no idEqual is present
// Otherwise, returns the lowest index for which isEqual(arr[]index, target) is true
function findIndexOf(arr, target, isEqual) {
if (!isEqual) {
return arr.indexOf(target);
}
for (var i = 0; i < arr.length; i++) {
if (isEqual(arr[i], target)) { return i; }
};
return -1;
}
/**
* Returns an object that queries targetIds.
* @param {Array} The array of targetData
* @param {String} The Id property name of target model
* @returns {Object} The object that queries targetIds
*/
function collectTargetIds(targetData, idPropertyName) {
var targetIds = [];
for (var i = 0; i < targetData.length; i++) {
var targetId = targetData[i][idPropertyName];
targetIds.push(targetId);
};
var IdQuery = {
inq: uniq(targetIds),
};
return IdQuery;
}
/**
* Find the idKey of a Model.
* @param {ModelConstructor} m - Model Constructor
* @returns {String}
*/
function idName(m) {
return m.definition.idName() || 'id';
}