loopback-datasource-juggler/lib/utils.js

478 lines
13 KiB
JavaScript

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
var traverse = require('traverse');
function safeRequire(module) {
try {
return require(module);
} catch (e) {
console.log('Run "npm install loopback-datasource-juggler ' + module
+ '" command to use loopback-datasource-juggler using ' + module
+ ' database engine');
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') {
var 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) {
var 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') {
var 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]);
result.splice(index, 1);
}
}
}
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
* @returns {exports.map|*}
*/
function removeUndefined(query) {
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) {
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 || [];
dst = dst.concat(target);
src.forEach(function (e) {
if (dst.indexOf(e) === -1) {
dst.push(e);
}
});
} else {
if (target && typeof target === 'object') {
Object.keys(target).forEach(function (key) {
dst[key] = target[key];
});
}
Object.keys(src).forEach(function (key) {
if (typeof src[key] !== 'object' || !src[key]) {
dst[key] = src[key];
}
else {
if (!target[key]) {
dst[key] = src[key]
} 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;
if (!global.Promise) {
cb = function(){};
cb.promise = {};
Object.defineProperty(cb.promise, 'then', { get: throwPromiseNotDefined });
Object.defineProperty(cb.promise, 'catch', { get: throwPromiseNotDefined });
return 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;
}
function throwPromiseNotDefined() {
throw new Error(
'Your Node runtime does support ES6 Promises. ' +
'Set "global.Promise" to your preferred implementation of promises.');
}