836 lines
25 KiB
JavaScript
Executable File
836 lines
25 KiB
JavaScript
Executable File
/**
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||
* Handle models (i.e. docs)
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* Serialization/deserialization
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* Copying
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* Querying, update
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*/
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var util = require('util')
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, _ = require('underscore')
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, modifierFunctions = {}
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, lastStepModifierFunctions = {}
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, comparisonFunctions = {}
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, logicalOperators = {}
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, arrayComparisonFunctions = {}
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;
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/**
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* Check a key, throw an error if the key is non valid
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* @param {String} k key
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* @param {Model} v value, needed to treat the Date edge case
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* Non-treatable edge cases here: if part of the object if of the form { $$date: number } or { $$deleted: true }
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* Its serialized-then-deserialized version it will transformed into a Date object
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* But you really need to want it to trigger such behaviour, even when warned not to use '$' at the beginning of the field names...
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*/
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function checkKey (k, v) {
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if (typeof k === 'number') {
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k = k.toString();
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}
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if (k[0] === '$' && !(k === '$$date' && typeof v === 'number') && !(k === '$$deleted' && v === true) && !(k === '$$indexCreated') && !(k === '$$indexRemoved')) {
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throw new Error('Field names cannot begin with the $ character');
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}
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if (k.indexOf('.') !== -1) {
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throw new Error('Field names cannot contain a .');
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}
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}
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/**
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* Check a DB object and throw an error if it's not valid
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* Works by applying the above checkKey function to all fields recursively
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*/
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function checkObject (obj) {
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if (util.isArray(obj)) {
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obj.forEach(function (o) {
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checkObject(o);
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});
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}
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if (typeof obj === 'object' && obj !== null) {
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Object.keys(obj).forEach(function (k) {
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checkKey(k, obj[k]);
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checkObject(obj[k]);
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});
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}
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}
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/**
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* Serialize an object to be persisted to a one-line string
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* For serialization/deserialization, we use the native JSON parser and not eval or Function
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* That gives us less freedom but data entered in the database may come from users
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* so eval and the like are not safe
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* Accepted primitive types: Number, String, Boolean, Date, null
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* Accepted secondary types: Objects, Arrays
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*/
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function serialize (obj) {
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var res;
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res = JSON.stringify(obj, function (k, v) {
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checkKey(k, v);
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if (v === undefined) { return undefined; }
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if (v === null) { return null; }
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// Hackish way of checking if object is Date (this way it works between execution contexts in node-webkit).
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// We can't use value directly because for dates it is already string in this function (date.toJSON was already called), so we use this
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if (typeof this[k].getTime === 'function') { return { $$date: this[k].getTime() }; }
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return v;
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});
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return res;
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}
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/**
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* From a one-line representation of an object generate by the serialize function
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* Return the object itself
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*/
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function deserialize (rawData) {
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return JSON.parse(rawData, function (k, v) {
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if (k === '$$date') { return new Date(v); }
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if (typeof v === 'string' || typeof v === 'number' || typeof v === 'boolean' || v === null) { return v; }
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if (v && v.$$date) { return v.$$date; }
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return v;
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});
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}
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/**
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* Deep copy a DB object
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* The optional strictKeys flag (defaulting to false) indicates whether to copy everything or only fields
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* where the keys are valid, i.e. don't begin with $ and don't contain a .
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*/
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function deepCopy (obj, strictKeys) {
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var res;
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if ( typeof obj === 'boolean' ||
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typeof obj === 'number' ||
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typeof obj === 'string' ||
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obj === null ||
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(util.isDate(obj)) ) {
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return obj;
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}
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if (util.isArray(obj)) {
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res = [];
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obj.forEach(function (o) { res.push(deepCopy(o, strictKeys)); });
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return res;
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}
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if (typeof obj === 'object') {
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res = {};
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Object.keys(obj).forEach(function (k) {
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if (!strictKeys || (k[0] !== '$' && k.indexOf('.') === -1)) {
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res[k] = deepCopy(obj[k], strictKeys);
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}
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});
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return res;
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}
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return undefined; // For now everything else is undefined. We should probably throw an error instead
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}
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/**
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* Tells if an object is a primitive type or a "real" object
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* Arrays are considered primitive
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*/
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function isPrimitiveType (obj) {
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return ( typeof obj === 'boolean' ||
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typeof obj === 'number' ||
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typeof obj === 'string' ||
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obj === null ||
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util.isDate(obj) ||
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util.isArray(obj));
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}
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/**
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* Utility functions for comparing things
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* Assumes type checking was already done (a and b already have the same type)
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* compareNSB works for numbers, strings and booleans
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*/
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function compareNSB (a, b) {
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if (a < b) { return -1; }
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if (a > b) { return 1; }
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return 0;
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}
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function compareArrays (a, b) {
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var i, comp;
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for (i = 0; i < Math.min(a.length, b.length); i += 1) {
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comp = compareThings(a[i], b[i]);
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if (comp !== 0) { return comp; }
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}
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// Common section was identical, longest one wins
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return compareNSB(a.length, b.length);
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}
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/**
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* Compare { things U undefined }
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* Things are defined as any native types (string, number, boolean, null, date) and objects
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* We need to compare with undefined as it will be used in indexes
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* In the case of objects and arrays, we deep-compare
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* If two objects dont have the same type, the (arbitrary) type hierarchy is: undefined, null, number, strings, boolean, dates, arrays, objects
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* Return -1 if a < b, 1 if a > b and 0 if a = b (note that equality here is NOT the same as defined in areThingsEqual!)
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*
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* @param {Function} _compareStrings String comparing function, returning -1, 0 or 1, overriding default string comparison (useful for languages with accented letters)
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*/
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function compareThings (a, b, _compareStrings) {
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var aKeys, bKeys, comp, i
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, compareStrings = _compareStrings || compareNSB;
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// undefined
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if (a === undefined) { return b === undefined ? 0 : -1; }
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if (b === undefined) { return a === undefined ? 0 : 1; }
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// null
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if (a === null) { return b === null ? 0 : -1; }
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if (b === null) { return a === null ? 0 : 1; }
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// Numbers
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if (typeof a === 'number') { return typeof b === 'number' ? compareNSB(a, b) : -1; }
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if (typeof b === 'number') { return typeof a === 'number' ? compareNSB(a, b) : 1; }
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// Strings
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if (typeof a === 'string') { return typeof b === 'string' ? compareStrings(a, b) : -1; }
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if (typeof b === 'string') { return typeof a === 'string' ? compareStrings(a, b) : 1; }
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// Booleans
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if (typeof a === 'boolean') { return typeof b === 'boolean' ? compareNSB(a, b) : -1; }
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if (typeof b === 'boolean') { return typeof a === 'boolean' ? compareNSB(a, b) : 1; }
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// Dates
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if (util.isDate(a)) { return util.isDate(b) ? compareNSB(a.getTime(), b.getTime()) : -1; }
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if (util.isDate(b)) { return util.isDate(a) ? compareNSB(a.getTime(), b.getTime()) : 1; }
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// Arrays (first element is most significant and so on)
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if (util.isArray(a)) { return util.isArray(b) ? compareArrays(a, b) : -1; }
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if (util.isArray(b)) { return util.isArray(a) ? compareArrays(a, b) : 1; }
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// Objects
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aKeys = Object.keys(a).sort();
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bKeys = Object.keys(b).sort();
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for (i = 0; i < Math.min(aKeys.length, bKeys.length); i += 1) {
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comp = compareThings(a[aKeys[i]], b[bKeys[i]]);
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if (comp !== 0) { return comp; }
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}
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return compareNSB(aKeys.length, bKeys.length);
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}
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// ==============================================================
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// Updating documents
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// ==============================================================
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/**
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* The signature of modifier functions is as follows
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* Their structure is always the same: recursively follow the dot notation while creating
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* the nested documents if needed, then apply the "last step modifier"
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* @param {Object} obj The model to modify
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* @param {String} field Can contain dots, in that case that means we will set a subfield recursively
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* @param {Model} value
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*/
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/**
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* Set a field to a new value
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*/
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lastStepModifierFunctions.$set = function (obj, field, value) {
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obj[field] = value;
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};
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/**
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* Unset a field
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*/
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lastStepModifierFunctions.$unset = function (obj, field, value) {
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delete obj[field];
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};
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/**
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* Push an element to the end of an array field
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* Optional modifier $each instead of value to push several values
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* Optional modifier $slice to slice the resulting array, see https://docs.mongodb.org/manual/reference/operator/update/slice/
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* Différeence with MongoDB: if $slice is specified and not $each, we act as if value is an empty array
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*/
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lastStepModifierFunctions.$push = function (obj, field, value) {
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// Create the array if it doesn't exist
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if (!obj.hasOwnProperty(field)) { obj[field] = []; }
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if (!util.isArray(obj[field])) { throw new Error("Can't $push an element on non-array values"); }
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||
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if (value !== null && typeof value === 'object' && value.$slice && value.$each === undefined) {
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value.$each = [];
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}
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if (value !== null && typeof value === 'object' && value.$each) {
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if (Object.keys(value).length >= 3 || (Object.keys(value).length === 2 && value.$slice === undefined)) { throw new Error("Can only use $slice in cunjunction with $each when $push to array"); }
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if (!util.isArray(value.$each)) { throw new Error("$each requires an array value"); }
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value.$each.forEach(function (v) {
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obj[field].push(v);
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});
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||
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if (value.$slice === undefined || typeof value.$slice !== 'number') { return; }
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||
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if (value.$slice === 0) {
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obj[field] = [];
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||
} else {
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var start, end, n = obj[field].length;
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if (value.$slice < 0) {
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start = Math.max(0, n + value.$slice);
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||
end = n;
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||
} else if (value.$slice > 0) {
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start = 0;
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||
end = Math.min(n, value.$slice);
|
||
}
|
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obj[field] = obj[field].slice(start, end);
|
||
}
|
||
} else {
|
||
obj[field].push(value);
|
||
}
|
||
};
|
||
|
||
|
||
/**
|
||
* Add an element to an array field only if it is not already in it
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||
* No modification if the element is already in the array
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||
* Note that it doesn't check whether the original array contains duplicates
|
||
*/
|
||
lastStepModifierFunctions.$addToSet = function (obj, field, value) {
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var addToSet = true;
|
||
|
||
// Create the array if it doesn't exist
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if (!obj.hasOwnProperty(field)) { obj[field] = []; }
|
||
|
||
if (!util.isArray(obj[field])) { throw new Error("Can't $addToSet an element on non-array values"); }
|
||
|
||
if (value !== null && typeof value === 'object' && value.$each) {
|
||
if (Object.keys(value).length > 1) { throw new Error("Can't use another field in conjunction with $each"); }
|
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if (!util.isArray(value.$each)) { throw new Error("$each requires an array value"); }
|
||
|
||
value.$each.forEach(function (v) {
|
||
lastStepModifierFunctions.$addToSet(obj, field, v);
|
||
});
|
||
} else {
|
||
obj[field].forEach(function (v) {
|
||
if (compareThings(v, value) === 0) { addToSet = false; }
|
||
});
|
||
if (addToSet) { obj[field].push(value); }
|
||
}
|
||
};
|
||
|
||
|
||
/**
|
||
* Remove the first or last element of an array
|
||
*/
|
||
lastStepModifierFunctions.$pop = function (obj, field, value) {
|
||
if (!util.isArray(obj[field])) { throw new Error("Can't $pop an element from non-array values"); }
|
||
if (typeof value !== 'number') { throw new Error(value + " isn't an integer, can't use it with $pop"); }
|
||
if (value === 0) { return; }
|
||
|
||
if (value > 0) {
|
||
obj[field] = obj[field].slice(0, obj[field].length - 1);
|
||
} else {
|
||
obj[field] = obj[field].slice(1);
|
||
}
|
||
};
|
||
|
||
|
||
/**
|
||
* Removes all instances of a value from an existing array
|
||
*/
|
||
lastStepModifierFunctions.$pull = function (obj, field, value) {
|
||
var arr, i;
|
||
|
||
if (!util.isArray(obj[field])) { throw new Error("Can't $pull an element from non-array values"); }
|
||
|
||
arr = obj[field];
|
||
for (i = arr.length - 1; i >= 0; i -= 1) {
|
||
if (match(arr[i], value)) {
|
||
arr.splice(i, 1);
|
||
}
|
||
}
|
||
};
|
||
|
||
|
||
/**
|
||
* Increment a numeric field's value
|
||
*/
|
||
lastStepModifierFunctions.$inc = function (obj, field, value) {
|
||
if (typeof value !== 'number') { throw new Error(value + " must be a number"); }
|
||
|
||
if (typeof obj[field] !== 'number') {
|
||
if (!_.has(obj, field)) {
|
||
obj[field] = value;
|
||
} else {
|
||
throw new Error("Don't use the $inc modifier on non-number fields");
|
||
}
|
||
} else {
|
||
obj[field] += value;
|
||
}
|
||
};
|
||
|
||
/**
|
||
* Updates the value of the field, only if specified field is greater than the current value of the field
|
||
*/
|
||
lastStepModifierFunctions.$max = function (obj, field, value) {
|
||
if (typeof obj[field] === 'undefined') {
|
||
obj[field] = value;
|
||
} else if (value > obj[field]) {
|
||
obj[field] = value;
|
||
}
|
||
};
|
||
|
||
/**
|
||
* Updates the value of the field, only if specified field is smaller than the current value of the field
|
||
*/
|
||
lastStepModifierFunctions.$min = function (obj, field, value) {
|
||
if (typeof obj[field] === 'undefined') {
|
||
obj[field] = value;
|
||
} else if (value < obj[field]) {
|
||
obj[field] = value;
|
||
}
|
||
};
|
||
|
||
// Given its name, create the complete modifier function
|
||
function createModifierFunction (modifier) {
|
||
return function (obj, field, value) {
|
||
var fieldParts = typeof field === 'string' ? field.split('.') : field;
|
||
|
||
if (fieldParts.length === 1) {
|
||
lastStepModifierFunctions[modifier](obj, field, value);
|
||
} else {
|
||
if (obj[fieldParts[0]] === undefined) {
|
||
if (modifier === '$unset') { return; } // Bad looking specific fix, needs to be generalized modifiers that behave like $unset are implemented
|
||
obj[fieldParts[0]] = {};
|
||
}
|
||
modifierFunctions[modifier](obj[fieldParts[0]], fieldParts.slice(1), value);
|
||
}
|
||
};
|
||
}
|
||
|
||
// Actually create all modifier functions
|
||
Object.keys(lastStepModifierFunctions).forEach(function (modifier) {
|
||
modifierFunctions[modifier] = createModifierFunction(modifier);
|
||
});
|
||
|
||
|
||
/**
|
||
* Modify a DB object according to an update query
|
||
*/
|
||
function modify (obj, updateQuery) {
|
||
var keys = Object.keys(updateQuery)
|
||
, firstChars = _.map(keys, function (item) { return item[0]; })
|
||
, dollarFirstChars = _.filter(firstChars, function (c) { return c === '$'; })
|
||
, newDoc, modifiers
|
||
;
|
||
|
||
if (keys.indexOf('_id') !== -1 && updateQuery._id !== obj._id) { throw new Error("You cannot change a document's _id"); }
|
||
|
||
if (dollarFirstChars.length !== 0 && dollarFirstChars.length !== firstChars.length) {
|
||
throw new Error("You cannot mix modifiers and normal fields");
|
||
}
|
||
|
||
if (dollarFirstChars.length === 0) {
|
||
// Simply replace the object with the update query contents
|
||
newDoc = deepCopy(updateQuery);
|
||
newDoc._id = obj._id;
|
||
} else {
|
||
// Apply modifiers
|
||
modifiers = _.uniq(keys);
|
||
newDoc = deepCopy(obj);
|
||
modifiers.forEach(function (m) {
|
||
var keys;
|
||
|
||
if (!modifierFunctions[m]) { throw new Error("Unknown modifier " + m); }
|
||
|
||
// Can't rely on Object.keys throwing on non objects since ES6
|
||
// Not 100% satisfying as non objects can be interpreted as objects but no false negatives so we can live with it
|
||
if (typeof updateQuery[m] !== 'object') {
|
||
throw new Error("Modifier " + m + "'s argument must be an object");
|
||
}
|
||
|
||
keys = Object.keys(updateQuery[m]);
|
||
keys.forEach(function (k) {
|
||
modifierFunctions[m](newDoc, k, updateQuery[m][k]);
|
||
});
|
||
});
|
||
}
|
||
|
||
// Check result is valid and return it
|
||
checkObject(newDoc);
|
||
|
||
if (obj._id !== newDoc._id) { throw new Error("You can't change a document's _id"); }
|
||
return newDoc;
|
||
};
|
||
|
||
|
||
// ==============================================================
|
||
// Finding documents
|
||
// ==============================================================
|
||
|
||
/**
|
||
* Get a value from object with dot notation
|
||
* @param {Object} obj
|
||
* @param {String} field
|
||
*/
|
||
function getDotValue (obj, field) {
|
||
var fieldParts = typeof field === 'string' ? field.split('.') : field
|
||
, i, objs;
|
||
|
||
if (!obj) { return undefined; } // field cannot be empty so that means we should return undefined so that nothing can match
|
||
|
||
if (fieldParts.length === 0) { return obj; }
|
||
|
||
if (fieldParts.length === 1) { return obj[fieldParts[0]]; }
|
||
|
||
if (util.isArray(obj[fieldParts[0]])) {
|
||
// If the next field is an integer, return only this item of the array
|
||
i = parseInt(fieldParts[1], 10);
|
||
if (typeof i === 'number' && !isNaN(i)) {
|
||
return getDotValue(obj[fieldParts[0]][i], fieldParts.slice(2))
|
||
}
|
||
|
||
// Return the array of values
|
||
objs = new Array();
|
||
for (i = 0; i < obj[fieldParts[0]].length; i += 1) {
|
||
objs.push(getDotValue(obj[fieldParts[0]][i], fieldParts.slice(1)));
|
||
}
|
||
return objs;
|
||
} else {
|
||
return getDotValue(obj[fieldParts[0]], fieldParts.slice(1));
|
||
}
|
||
}
|
||
|
||
|
||
/**
|
||
* Check whether 'things' are equal
|
||
* Things are defined as any native types (string, number, boolean, null, date) and objects
|
||
* In the case of object, we check deep equality
|
||
* Returns true if they are, false otherwise
|
||
*/
|
||
function areThingsEqual (a, b) {
|
||
var aKeys , bKeys , i;
|
||
|
||
// Strings, booleans, numbers, null
|
||
if (a === null || typeof a === 'string' || typeof a === 'boolean' || typeof a === 'number' ||
|
||
b === null || typeof b === 'string' || typeof b === 'boolean' || typeof b === 'number') { return a === b; }
|
||
|
||
// Dates
|
||
if (util.isDate(a) || util.isDate(b)) { return util.isDate(a) && util.isDate(b) && a.getTime() === b.getTime(); }
|
||
|
||
// Arrays (no match since arrays are used as a $in)
|
||
// undefined (no match since they mean field doesn't exist and can't be serialized)
|
||
if ((!(util.isArray(a) && util.isArray(b)) && (util.isArray(a) || util.isArray(b))) || a === undefined || b === undefined) { return false; }
|
||
|
||
// General objects (check for deep equality)
|
||
// a and b should be objects at this point
|
||
try {
|
||
aKeys = Object.keys(a);
|
||
bKeys = Object.keys(b);
|
||
} catch (e) {
|
||
return false;
|
||
}
|
||
|
||
if (aKeys.length !== bKeys.length) { return false; }
|
||
for (i = 0; i < aKeys.length; i += 1) {
|
||
if (bKeys.indexOf(aKeys[i]) === -1) { return false; }
|
||
if (!areThingsEqual(a[aKeys[i]], b[aKeys[i]])) { return false; }
|
||
}
|
||
return true;
|
||
}
|
||
|
||
|
||
/**
|
||
* Check that two values are comparable
|
||
*/
|
||
function areComparable (a, b) {
|
||
if (typeof a !== 'string' && typeof a !== 'number' && !util.isDate(a) &&
|
||
typeof b !== 'string' && typeof b !== 'number' && !util.isDate(b)) {
|
||
return false;
|
||
}
|
||
|
||
if (typeof a !== typeof b) { return false; }
|
||
|
||
return true;
|
||
}
|
||
|
||
|
||
/**
|
||
* Arithmetic and comparison operators
|
||
* @param {Native value} a Value in the object
|
||
* @param {Native value} b Value in the query
|
||
*/
|
||
comparisonFunctions.$lt = function (a, b) {
|
||
return areComparable(a, b) && a < b;
|
||
};
|
||
|
||
comparisonFunctions.$lte = function (a, b) {
|
||
return areComparable(a, b) && a <= b;
|
||
};
|
||
|
||
comparisonFunctions.$gt = function (a, b) {
|
||
return areComparable(a, b) && a > b;
|
||
};
|
||
|
||
comparisonFunctions.$gte = function (a, b) {
|
||
return areComparable(a, b) && a >= b;
|
||
};
|
||
|
||
comparisonFunctions.$ne = function (a, b) {
|
||
if (a === undefined) { return true; }
|
||
return !areThingsEqual(a, b);
|
||
};
|
||
|
||
comparisonFunctions.$in = function (a, b) {
|
||
var i;
|
||
|
||
if (!util.isArray(b)) { throw new Error("$in operator called with a non-array"); }
|
||
|
||
for (i = 0; i < b.length; i += 1) {
|
||
if (areThingsEqual(a, b[i])) { return true; }
|
||
}
|
||
|
||
return false;
|
||
};
|
||
|
||
comparisonFunctions.$nin = function (a, b) {
|
||
if (!util.isArray(b)) { throw new Error("$nin operator called with a non-array"); }
|
||
|
||
return !comparisonFunctions.$in(a, b);
|
||
};
|
||
|
||
comparisonFunctions.$regex = function (a, b) {
|
||
if (!util.isRegExp(b)) { throw new Error("$regex operator called with non regular expression"); }
|
||
|
||
if (typeof a !== 'string') {
|
||
return false
|
||
} else {
|
||
return b.test(a);
|
||
}
|
||
};
|
||
|
||
comparisonFunctions.$exists = function (value, exists) {
|
||
if (exists || exists === '') { // This will be true for all values of exists except false, null, undefined and 0
|
||
exists = true; // That's strange behaviour (we should only use true/false) but that's the way Mongo does it...
|
||
} else {
|
||
exists = false;
|
||
}
|
||
|
||
if (value === undefined) {
|
||
return !exists
|
||
} else {
|
||
return exists;
|
||
}
|
||
};
|
||
|
||
// Specific to arrays
|
||
comparisonFunctions.$size = function (obj, value) {
|
||
if (!util.isArray(obj)) { return false; }
|
||
if (value % 1 !== 0) { throw new Error("$size operator called without an integer"); }
|
||
|
||
return (obj.length == value);
|
||
};
|
||
comparisonFunctions.$elemMatch = function (obj, value) {
|
||
if (!util.isArray(obj)) { return false; }
|
||
var i = obj.length;
|
||
var result = false; // Initialize result
|
||
while (i--) {
|
||
if (match(obj[i], value)) { // If match for array element, return true
|
||
result = true;
|
||
break;
|
||
}
|
||
}
|
||
return result;
|
||
};
|
||
arrayComparisonFunctions.$size = true;
|
||
arrayComparisonFunctions.$elemMatch = true;
|
||
|
||
|
||
/**
|
||
* Match any of the subqueries
|
||
* @param {Model} obj
|
||
* @param {Array of Queries} query
|
||
*/
|
||
logicalOperators.$or = function (obj, query) {
|
||
var i;
|
||
|
||
if (!util.isArray(query)) { throw new Error("$or operator used without an array"); }
|
||
|
||
for (i = 0; i < query.length; i += 1) {
|
||
if (match(obj, query[i])) { return true; }
|
||
}
|
||
|
||
return false;
|
||
};
|
||
|
||
|
||
/**
|
||
* Match all of the subqueries
|
||
* @param {Model} obj
|
||
* @param {Array of Queries} query
|
||
*/
|
||
logicalOperators.$and = function (obj, query) {
|
||
var i;
|
||
|
||
if (!util.isArray(query)) { throw new Error("$and operator used without an array"); }
|
||
|
||
for (i = 0; i < query.length; i += 1) {
|
||
if (!match(obj, query[i])) { return false; }
|
||
}
|
||
|
||
return true;
|
||
};
|
||
|
||
|
||
/**
|
||
* Inverted match of the query
|
||
* @param {Model} obj
|
||
* @param {Query} query
|
||
*/
|
||
logicalOperators.$not = function (obj, query) {
|
||
return !match(obj, query);
|
||
};
|
||
|
||
|
||
/**
|
||
* Use a function to match
|
||
* @param {Model} obj
|
||
* @param {Query} query
|
||
*/
|
||
logicalOperators.$where = function (obj, fn) {
|
||
var result;
|
||
|
||
if (!_.isFunction(fn)) { throw new Error("$where operator used without a function"); }
|
||
|
||
result = fn.call(obj);
|
||
if (!_.isBoolean(result)) { throw new Error("$where function must return boolean"); }
|
||
|
||
return result;
|
||
};
|
||
|
||
|
||
/**
|
||
* Tell if a given document matches a query
|
||
* @param {Object} obj Document to check
|
||
* @param {Object} query
|
||
*/
|
||
function match (obj, query) {
|
||
var queryKeys, queryKey, queryValue, i;
|
||
|
||
// Primitive query against a primitive type
|
||
// This is a bit of a hack since we construct an object with an arbitrary key only to dereference it later
|
||
// But I don't have time for a cleaner implementation now
|
||
if (isPrimitiveType(obj) || isPrimitiveType(query)) {
|
||
return matchQueryPart({ needAKey: obj }, 'needAKey', query);
|
||
}
|
||
|
||
// Normal query
|
||
queryKeys = Object.keys(query);
|
||
for (i = 0; i < queryKeys.length; i += 1) {
|
||
queryKey = queryKeys[i];
|
||
queryValue = query[queryKey];
|
||
|
||
if (queryKey[0] === '$') {
|
||
if (!logicalOperators[queryKey]) { throw new Error("Unknown logical operator " + queryKey); }
|
||
if (!logicalOperators[queryKey](obj, queryValue)) { return false; }
|
||
} else {
|
||
if (!matchQueryPart(obj, queryKey, queryValue)) { return false; }
|
||
}
|
||
}
|
||
|
||
return true;
|
||
};
|
||
|
||
|
||
/**
|
||
* Match an object against a specific { key: value } part of a query
|
||
* if the treatObjAsValue flag is set, don't try to match every part separately, but the array as a whole
|
||
*/
|
||
function matchQueryPart (obj, queryKey, queryValue, treatObjAsValue) {
|
||
var objValue = getDotValue(obj, queryKey)
|
||
, i, keys, firstChars, dollarFirstChars;
|
||
|
||
// Check if the value is an array if we don't force a treatment as value
|
||
if (util.isArray(objValue) && !treatObjAsValue) {
|
||
// If the queryValue is an array, try to perform an exact match
|
||
if (util.isArray(queryValue)) {
|
||
return matchQueryPart(obj, queryKey, queryValue, true);
|
||
}
|
||
|
||
// Check if we are using an array-specific comparison function
|
||
if (queryValue !== null && typeof queryValue === 'object' && !util.isRegExp(queryValue)) {
|
||
keys = Object.keys(queryValue);
|
||
for (i = 0; i < keys.length; i += 1) {
|
||
if (arrayComparisonFunctions[keys[i]]) { return matchQueryPart(obj, queryKey, queryValue, true); }
|
||
}
|
||
}
|
||
|
||
// If not, treat it as an array of { obj, query } where there needs to be at least one match
|
||
for (i = 0; i < objValue.length; i += 1) {
|
||
if (matchQueryPart({ k: objValue[i] }, 'k', queryValue)) { return true; } // k here could be any string
|
||
}
|
||
return false;
|
||
}
|
||
|
||
// queryValue is an actual object. Determine whether it contains comparison operators
|
||
// or only normal fields. Mixed objects are not allowed
|
||
if (queryValue !== null && typeof queryValue === 'object' && !util.isRegExp(queryValue) && !util.isArray(queryValue)) {
|
||
keys = Object.keys(queryValue);
|
||
firstChars = _.map(keys, function (item) { return item[0]; });
|
||
dollarFirstChars = _.filter(firstChars, function (c) { return c === '$'; });
|
||
|
||
if (dollarFirstChars.length !== 0 && dollarFirstChars.length !== firstChars.length) {
|
||
throw new Error("You cannot mix operators and normal fields");
|
||
}
|
||
|
||
// queryValue is an object of this form: { $comparisonOperator1: value1, ... }
|
||
if (dollarFirstChars.length > 0) {
|
||
for (i = 0; i < keys.length; i += 1) {
|
||
if (!comparisonFunctions[keys[i]]) { throw new Error("Unknown comparison function " + keys[i]); }
|
||
|
||
if (!comparisonFunctions[keys[i]](objValue, queryValue[keys[i]])) { return false; }
|
||
}
|
||
return true;
|
||
}
|
||
}
|
||
|
||
// Using regular expressions with basic querying
|
||
if (util.isRegExp(queryValue)) { return comparisonFunctions.$regex(objValue, queryValue); }
|
||
|
||
// queryValue is either a native value or a normal object
|
||
// Basic matching is possible
|
||
if (!areThingsEqual(objValue, queryValue)) { return false; }
|
||
|
||
return true;
|
||
}
|
||
|
||
|
||
// Interface
|
||
module.exports.serialize = serialize;
|
||
module.exports.deserialize = deserialize;
|
||
module.exports.deepCopy = deepCopy;
|
||
module.exports.checkObject = checkObject;
|
||
module.exports.isPrimitiveType = isPrimitiveType;
|
||
module.exports.modify = modify;
|
||
module.exports.getDotValue = getDotValue;
|
||
module.exports.match = match;
|
||
module.exports.areThingsEqual = areThingsEqual;
|
||
module.exports.compareThings = compareThings;
|