mirror of https://github.com/seald/nedb
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
827 lines
26 KiB
827 lines
26 KiB
/**
|
|
* Handle models (i.e. docs)
|
|
* Serialization/deserialization
|
|
* Copying
|
|
* Querying, update
|
|
* @module model
|
|
* @private
|
|
*/
|
|
const { uniq, isDate, isRegExp } = require('./utils.js')
|
|
|
|
/**
|
|
* Check a key, throw an error if the key is non valid
|
|
* @param {string} k key
|
|
* @param {document} v value, needed to treat the Date edge case
|
|
* Non-treatable edge cases here: if part of the object if of the form { $$date: number } or { $$deleted: true }
|
|
* Its serialized-then-deserialized version it will transformed into a Date object
|
|
* But you really need to want it to trigger such behaviour, even when warned not to use '$' at the beginning of the field names...
|
|
* @private
|
|
*/
|
|
const checkKey = (k, v) => {
|
|
if (typeof k === 'number') k = k.toString()
|
|
|
|
if (
|
|
k[0] === '$' &&
|
|
!(k === '$$date' && typeof v === 'number') &&
|
|
!(k === '$$deleted' && v === true) &&
|
|
!(k === '$$indexCreated') &&
|
|
!(k === '$$indexRemoved')
|
|
) throw new Error('Field names cannot begin with the $ character')
|
|
|
|
if (k.indexOf('.') !== -1) throw new Error('Field names cannot contain a .')
|
|
}
|
|
|
|
/**
|
|
* Check a DB object and throw an error if it's not valid
|
|
* Works by applying the above checkKey function to all fields recursively
|
|
* @param {document|document[]} obj
|
|
* @alias module:model.checkObject
|
|
*/
|
|
const checkObject = obj => {
|
|
if (Array.isArray(obj)) {
|
|
obj.forEach(o => {
|
|
checkObject(o)
|
|
})
|
|
}
|
|
|
|
if (typeof obj === 'object' && obj !== null) {
|
|
for (const k in obj) {
|
|
if (Object.prototype.hasOwnProperty.call(obj, k)) {
|
|
checkKey(k, obj[k])
|
|
checkObject(obj[k])
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Serialize an object to be persisted to a one-line string
|
|
* For serialization/deserialization, we use the native JSON parser and not eval or Function
|
|
* That gives us less freedom but data entered in the database may come from users
|
|
* so eval and the like are not safe
|
|
* Accepted primitive types: Number, String, Boolean, Date, null
|
|
* Accepted secondary types: Objects, Arrays
|
|
* @param {document} obj
|
|
* @return {string}
|
|
* @alias module:model.serialize
|
|
*/
|
|
const serialize = obj => {
|
|
return JSON.stringify(obj, function (k, v) {
|
|
checkKey(k, v)
|
|
|
|
if (v === undefined) return undefined
|
|
if (v === null) return null
|
|
|
|
// Hackish way of checking if object is Date (this way it works between execution contexts in node-webkit).
|
|
// 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
|
|
if (typeof this[k].getTime === 'function') return { $$date: this[k].getTime() }
|
|
|
|
return v
|
|
})
|
|
}
|
|
|
|
/**
|
|
* From a one-line representation of an object generate by the serialize function
|
|
* Return the object itself
|
|
* @param {string} rawData
|
|
* @return {document}
|
|
* @alias module:model.deserialize
|
|
*/
|
|
const deserialize = rawData => JSON.parse(rawData, function (k, v) {
|
|
if (k === '$$date') return new Date(v)
|
|
if (
|
|
typeof v === 'string' ||
|
|
typeof v === 'number' ||
|
|
typeof v === 'boolean' ||
|
|
v === null
|
|
) return v
|
|
if (v && v.$$date) return v.$$date
|
|
|
|
return v
|
|
})
|
|
|
|
/**
|
|
* Deep copy a DB object
|
|
* The optional strictKeys flag (defaulting to false) indicates whether to copy everything or only fields
|
|
* where the keys are valid, i.e. don't begin with $ and don't contain a .
|
|
* @param {?document} obj
|
|
* @param {boolean} [strictKeys=false]
|
|
* @return {?document}
|
|
* @alias module:modelel:(.*)
|
|
*/
|
|
function deepCopy (obj, strictKeys) {
|
|
if (
|
|
typeof obj === 'boolean' ||
|
|
typeof obj === 'number' ||
|
|
typeof obj === 'string' ||
|
|
obj === null ||
|
|
(isDate(obj))
|
|
) return obj
|
|
|
|
if (Array.isArray(obj)) return obj.map(o => deepCopy(o, strictKeys))
|
|
|
|
if (typeof obj === 'object') {
|
|
const res = {}
|
|
for (const k in obj) {
|
|
if (
|
|
Object.prototype.hasOwnProperty.call(obj, k) &&
|
|
(!strictKeys || (k[0] !== '$' && k.indexOf('.') === -1))
|
|
) {
|
|
res[k] = deepCopy(obj[k], strictKeys)
|
|
}
|
|
}
|
|
return res
|
|
}
|
|
|
|
return undefined // For now everything else is undefined. We should probably throw an error instead
|
|
}
|
|
|
|
/**
|
|
* Tells if an object is a primitive type or a "real" object
|
|
* Arrays are considered primitive
|
|
* @param {*} obj
|
|
* @return {boolean}
|
|
* @alias module:modelel:(.*)
|
|
*/
|
|
const isPrimitiveType = obj => (
|
|
typeof obj === 'boolean' ||
|
|
typeof obj === 'number' ||
|
|
typeof obj === 'string' ||
|
|
obj === null ||
|
|
isDate(obj) ||
|
|
Array.isArray(obj)
|
|
)
|
|
|
|
/**
|
|
* Utility functions for comparing things
|
|
* Assumes type checking was already done (a and b already have the same type)
|
|
* compareNSB works for numbers, strings and booleans
|
|
* @param {number|string|boolean} a
|
|
* @param {number|string|boolean} b
|
|
* @return {number} 0 if a == b, 1 i a > b, -1 if a < b
|
|
* @private
|
|
*/
|
|
const compareNSB = (a, b) => {
|
|
if (a < b) return -1
|
|
if (a > b) return 1
|
|
return 0
|
|
}
|
|
|
|
/**
|
|
* Utility function for comparing array
|
|
* Assumes type checking was already done (a and b already have the same type)
|
|
* compareNSB works for numbers, strings and booleans
|
|
* @param {Array} a
|
|
* @param {Array} b
|
|
* @return {number} 0 if arrays have the same length and all elements equal one another. Else either 1 or -1.
|
|
* @private
|
|
*/
|
|
const compareArrays = (a, b) => {
|
|
const minLength = Math.min(a.length, b.length)
|
|
for (let i = 0; i < minLength; i += 1) {
|
|
const comp = compareThings(a[i], b[i])
|
|
|
|
if (comp !== 0) return comp
|
|
}
|
|
|
|
// Common section was identical, longest one wins
|
|
return compareNSB(a.length, b.length)
|
|
}
|
|
|
|
/**
|
|
* Compare { things U undefined }
|
|
* Things are defined as any native types (string, number, boolean, null, date) and objects
|
|
* We need to compare with undefined as it will be used in indexes
|
|
* In the case of objects and arrays, we deep-compare
|
|
* If two objects dont have the same type, the (arbitrary) type hierarchy is: undefined, null, number, strings, boolean, dates, arrays, objects
|
|
* 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!)
|
|
* @param {*} a
|
|
* @param {*} b
|
|
* @param {compareStrings} [_compareStrings] String comparing function, returning -1, 0 or 1, overriding default string comparison (useful for languages with accented letters)
|
|
* @return {number}
|
|
* @alias module:model.compareThings
|
|
*/
|
|
const compareThings = (a, b, _compareStrings) => {
|
|
const compareStrings = _compareStrings || compareNSB
|
|
|
|
// undefined
|
|
if (a === undefined) return b === undefined ? 0 : -1
|
|
if (b === undefined) return 1 // no need to test if a === undefined
|
|
|
|
// null
|
|
if (a === null) return b === null ? 0 : -1
|
|
if (b === null) return 1 // no need to test if a === null
|
|
|
|
// Numbers
|
|
if (typeof a === 'number') return typeof b === 'number' ? compareNSB(a, b) : -1
|
|
if (typeof b === 'number') return typeof a === 'number' ? compareNSB(a, b) : 1
|
|
|
|
// Strings
|
|
if (typeof a === 'string') return typeof b === 'string' ? compareStrings(a, b) : -1
|
|
if (typeof b === 'string') return typeof a === 'string' ? compareStrings(a, b) : 1
|
|
|
|
// Booleans
|
|
if (typeof a === 'boolean') return typeof b === 'boolean' ? compareNSB(a, b) : -1
|
|
if (typeof b === 'boolean') return typeof a === 'boolean' ? compareNSB(a, b) : 1
|
|
|
|
// Dates
|
|
if (isDate(a)) return isDate(b) ? compareNSB(a.getTime(), b.getTime()) : -1
|
|
if (isDate(b)) return isDate(a) ? compareNSB(a.getTime(), b.getTime()) : 1
|
|
|
|
// Arrays (first element is most significant and so on)
|
|
if (Array.isArray(a)) return Array.isArray(b) ? compareArrays(a, b) : -1
|
|
if (Array.isArray(b)) return Array.isArray(a) ? compareArrays(a, b) : 1
|
|
|
|
// Objects
|
|
const aKeys = Object.keys(a).sort()
|
|
const bKeys = Object.keys(b).sort()
|
|
|
|
for (let i = 0; i < Math.min(aKeys.length, bKeys.length); i += 1) {
|
|
const comp = compareThings(a[aKeys[i]], b[bKeys[i]])
|
|
|
|
if (comp !== 0) return comp
|
|
}
|
|
|
|
return compareNSB(aKeys.length, bKeys.length)
|
|
}
|
|
|
|
// ==============================================================
|
|
// Updating documents
|
|
// ==============================================================
|
|
|
|
/**
|
|
* @callback modifierFunction
|
|
* The signature of modifier functions is as follows
|
|
* Their structure is always the same: recursively follow the dot notation while creating
|
|
* the nested documents if needed, then apply the "last step modifier"
|
|
* @param {Object} obj The model to modify
|
|
* @param {String} field Can contain dots, in that case that means we will set a subfield recursively
|
|
* @param {document} value
|
|
*/
|
|
|
|
/**
|
|
* Create the complete modifier function
|
|
* @param {modifierFunction} lastStepModifierFunction a lastStepModifierFunction
|
|
* @param {boolean} [unset = false] Bad looking specific fix, needs to be generalized modifiers that behave like $unset are implemented
|
|
* @return {modifierFunction}
|
|
* @private
|
|
*/
|
|
const createModifierFunction = (lastStepModifierFunction, unset = false) => (obj, field, value) => {
|
|
const func = (obj, field, value) => {
|
|
const fieldParts = typeof field === 'string' ? field.split('.') : field
|
|
|
|
if (fieldParts.length === 1) lastStepModifierFunction(obj, field, value)
|
|
else {
|
|
if (obj[fieldParts[0]] === undefined) {
|
|
if (unset) return
|
|
obj[fieldParts[0]] = {}
|
|
}
|
|
func(obj[fieldParts[0]], fieldParts.slice(1), value)
|
|
}
|
|
}
|
|
return func(obj, field, value)
|
|
}
|
|
|
|
const $addToSetPartial = (obj, field, value) => {
|
|
// Create the array if it doesn't exist
|
|
if (!Object.prototype.hasOwnProperty.call(obj, field)) { obj[field] = [] }
|
|
|
|
if (!Array.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 $each')
|
|
if (!Array.isArray(value.$each)) throw new Error('$each requires an array value')
|
|
|
|
value.$each.forEach(v => {
|
|
$addToSetPartial(obj, field, v)
|
|
})
|
|
} else {
|
|
let addToSet = true
|
|
obj[field].forEach(v => {
|
|
if (compareThings(v, value) === 0) addToSet = false
|
|
})
|
|
if (addToSet) obj[field].push(value)
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @enum {modifierFunction}
|
|
*/
|
|
const modifierFunctions = {
|
|
/**
|
|
* Set a field to a new value
|
|
*/
|
|
$set: createModifierFunction((obj, field, value) => {
|
|
obj[field] = value
|
|
}),
|
|
/**
|
|
* Unset a field
|
|
*/
|
|
$unset: createModifierFunction((obj, field, value) => {
|
|
delete obj[field]
|
|
}, true),
|
|
/**
|
|
* Updates the value of the field, only if specified field is smaller than the current value of the field
|
|
*/
|
|
$min: createModifierFunction((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 greater than the current value of the field
|
|
*/
|
|
$max: createModifierFunction((obj, field, value) => {
|
|
if (typeof obj[field] === 'undefined') obj[field] = value
|
|
else if (value > obj[field]) obj[field] = value
|
|
}),
|
|
/**
|
|
* Increment a numeric field's value
|
|
*/
|
|
$inc: createModifierFunction((obj, field, value) => {
|
|
if (typeof value !== 'number') throw new Error(`${value} must be a number`)
|
|
|
|
if (typeof obj[field] !== 'number') {
|
|
if (!Object.prototype.hasOwnProperty.call(obj, field)) obj[field] = value
|
|
else throw new Error('Don\'t use the $inc modifier on non-number fields')
|
|
} else obj[field] += value
|
|
}),
|
|
/**
|
|
* Removes all instances of a value from an existing array
|
|
*/
|
|
$pull: createModifierFunction((obj, field, value) => {
|
|
if (!Array.isArray(obj[field])) throw new Error('Can\'t $pull an element from non-array values')
|
|
|
|
const arr = obj[field]
|
|
for (let i = arr.length - 1; i >= 0; i -= 1) {
|
|
if (match(arr[i], value)) arr.splice(i, 1)
|
|
}
|
|
}),
|
|
/**
|
|
* Remove the first or last element of an array
|
|
*/
|
|
$pop: createModifierFunction((obj, field, value) => {
|
|
if (!Array.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)
|
|
}),
|
|
/**
|
|
* Add an element to an array field only if it is not already in it
|
|
* No modification if the element is already in the array
|
|
* Note that it doesn't check whether the original array contains duplicates
|
|
*/
|
|
$addToSet: createModifierFunction($addToSetPartial),
|
|
/**
|
|
* Push an element to the end of an array field
|
|
* Optional modifier $each instead of value to push several values
|
|
* Optional modifier $slice to slice the resulting array, see https://docs.mongodb.org/manual/reference/operator/update/slice/
|
|
* Difference with MongoDB: if $slice is specified and not $each, we act as if value is an empty array
|
|
*/
|
|
$push: createModifierFunction((obj, field, value) => {
|
|
// Create the array if it doesn't exist
|
|
if (!Object.prototype.hasOwnProperty.call(obj, field)) obj[field] = []
|
|
|
|
if (!Array.isArray(obj[field])) throw new Error('Can\'t $push an element on non-array values')
|
|
|
|
if (
|
|
value !== null &&
|
|
typeof value === 'object' &&
|
|
value.$slice &&
|
|
value.$each === undefined
|
|
) value.$each = []
|
|
|
|
if (value !== null && typeof value === 'object' && value.$each) {
|
|
if (
|
|
Object.keys(value).length >= 3 ||
|
|
(Object.keys(value).length === 2 && value.$slice === undefined)
|
|
) throw new Error('Can only use $slice in cunjunction with $each when $push to array')
|
|
if (!Array.isArray(value.$each)) throw new Error('$each requires an array value')
|
|
|
|
value.$each.forEach(v => {
|
|
obj[field].push(v)
|
|
})
|
|
|
|
if (value.$slice === undefined || typeof value.$slice !== 'number') return
|
|
|
|
if (value.$slice === 0) obj[field] = []
|
|
else {
|
|
let start
|
|
let end
|
|
const n = obj[field].length
|
|
if (value.$slice < 0) {
|
|
start = Math.max(0, n + value.$slice)
|
|
end = n
|
|
} else if (value.$slice > 0) {
|
|
start = 0
|
|
end = Math.min(n, value.$slice)
|
|
}
|
|
obj[field] = obj[field].slice(start, end)
|
|
}
|
|
} else {
|
|
obj[field].push(value)
|
|
}
|
|
})
|
|
|
|
}
|
|
|
|
/**
|
|
* Modify a DB object according to an update query
|
|
* @param {document} obj
|
|
* @param {query} updateQuery
|
|
* @return {document}
|
|
* @alias module:model.modify
|
|
*/
|
|
const modify = (obj, updateQuery) => {
|
|
const keys = Object.keys(updateQuery)
|
|
const firstChars = keys.map(item => item[0])
|
|
const dollarFirstChars = firstChars.filter(c => c === '$')
|
|
let newDoc
|
|
let 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(m => {
|
|
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`)
|
|
|
|
const keys = Object.keys(updateQuery[m])
|
|
keys.forEach(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
|
|
* @return {*}
|
|
* @alias module:model.getDotValue
|
|
*/
|
|
const getDotValue = (obj, field) => {
|
|
const fieldParts = typeof field === 'string' ? field.split('.') : field
|
|
|
|
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 (Array.isArray(obj[fieldParts[0]])) {
|
|
// If the next field is an integer, return only this item of the array
|
|
const 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
|
|
return obj[fieldParts[0]].map(el => getDotValue(el, fieldParts.slice(1)))
|
|
} else return getDotValue(obj[fieldParts[0]], fieldParts.slice(1))
|
|
}
|
|
|
|
/**
|
|
* Get dot values for either a bunch of fields or just one.
|
|
*/
|
|
const getDotValues = (obj, fields) => {
|
|
if (!Array.isArray(fields)) throw new Error('fields must be an Array')
|
|
if (fields.length > 1) {
|
|
const key = {}
|
|
for (const field of fields) {
|
|
key[field] = getDotValue(obj, field)
|
|
}
|
|
return key
|
|
} else return getDotValue(obj, fields[0])
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
* @param {*} a
|
|
* @param {*} a
|
|
* @return {boolean}
|
|
* @alias module:model.areThingsEqual
|
|
*/
|
|
const areThingsEqual = (a, b) => {
|
|
// 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 (isDate(a) || isDate(b)) return isDate(a) && 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 (
|
|
(!(Array.isArray(a) && Array.isArray(b)) && (Array.isArray(a) || Array.isArray(b))) ||
|
|
a === undefined || b === undefined
|
|
) return false
|
|
|
|
// General objects (check for deep equality)
|
|
// a and b should be objects at this point
|
|
let aKeys
|
|
let bKeys
|
|
try {
|
|
aKeys = Object.keys(a)
|
|
bKeys = Object.keys(b)
|
|
} catch (e) {
|
|
return false
|
|
}
|
|
|
|
if (aKeys.length !== bKeys.length) return false
|
|
for (const el of aKeys) {
|
|
if (bKeys.indexOf(el) === -1) return false
|
|
if (!areThingsEqual(a[el], b[el])) return false
|
|
}
|
|
return true
|
|
}
|
|
|
|
/**
|
|
* Check that two values are comparable
|
|
* @param {*} a
|
|
* @param {*} a
|
|
* @return {boolean}
|
|
* @private
|
|
*/
|
|
const areComparable = (a, b) => {
|
|
if (
|
|
typeof a !== 'string' &&
|
|
typeof a !== 'number' &&
|
|
!isDate(a) &&
|
|
typeof b !== 'string' &&
|
|
typeof b !== 'number' &&
|
|
!isDate(b)
|
|
) return false
|
|
|
|
if (typeof a !== typeof b) return false
|
|
|
|
return true
|
|
}
|
|
|
|
/**
|
|
* @callback comparisonOperator
|
|
* Arithmetic and comparison operators
|
|
* @param {*} a Value in the object
|
|
* @param {*} b Value in the query
|
|
* @return {boolean}
|
|
*/
|
|
|
|
/**
|
|
* @enum {comparisonOperator}
|
|
*/
|
|
const comparisonFunctions = {
|
|
/** Lower than */
|
|
$lt: (a, b) => areComparable(a, b) && a < b,
|
|
/** Lower than or equals */
|
|
$lte: (a, b) => areComparable(a, b) && a <= b,
|
|
/** Greater than */
|
|
$gt: (a, b) => areComparable(a, b) && a > b,
|
|
/** Greater than or equals */
|
|
$gte: (a, b) => areComparable(a, b) && a >= b,
|
|
/** Does not equal */
|
|
$ne: (a, b) => a === undefined || !areThingsEqual(a, b),
|
|
/** Is in Array */
|
|
$in: (a, b) => {
|
|
if (!Array.isArray(b)) throw new Error('$in operator called with a non-array')
|
|
|
|
for (const el of b) {
|
|
if (areThingsEqual(a, el)) return true
|
|
}
|
|
|
|
return false
|
|
},
|
|
/** Is not in Array */
|
|
$nin: (a, b) => {
|
|
if (!Array.isArray(b)) throw new Error('$nin operator called with a non-array')
|
|
|
|
return !comparisonFunctions.$in(a, b)
|
|
},
|
|
/** Matches Regexp */
|
|
$regex: (a, b) => {
|
|
if (!isRegExp(b)) throw new Error('$regex operator called with non regular expression')
|
|
|
|
if (typeof a !== 'string') return false
|
|
else return b.test(a)
|
|
},
|
|
/** Returns true if field exists */
|
|
$exists: (a, b) => {
|
|
// This will be true for all values of stat except false, null, undefined and 0
|
|
// That's strange behaviour (we should only use true/false) but that's the way Mongo does it...
|
|
if (b || b === '') b = true
|
|
else b = false
|
|
|
|
if (a === undefined) return !b
|
|
else return b
|
|
},
|
|
/** Specific to Arrays, returns true if a length equals b */
|
|
$size: (a, b) => {
|
|
if (!Array.isArray(a)) return false
|
|
if (b % 1 !== 0) throw new Error('$size operator called without an integer')
|
|
|
|
return a.length === b
|
|
},
|
|
/** Specific to Arrays, returns true if some elements of a match the query b */
|
|
$elemMatch: (a, b) => {
|
|
if (!Array.isArray(a)) return false
|
|
return a.some(el => match(el, b))
|
|
}
|
|
}
|
|
|
|
const arrayComparisonFunctions = { $size: true, $elemMatch: true }
|
|
|
|
/**
|
|
* @enum
|
|
*/
|
|
const logicalOperators = {
|
|
/**
|
|
* Match any of the subqueries
|
|
* @param {document} obj
|
|
* @param {query[]} query
|
|
* @return {boolean}
|
|
*/
|
|
$or: (obj, query) => {
|
|
if (!Array.isArray(query)) throw new Error('$or operator used without an array')
|
|
|
|
for (let i = 0; i < query.length; i += 1) {
|
|
if (match(obj, query[i])) return true
|
|
}
|
|
|
|
return false
|
|
},
|
|
/**
|
|
* Match all of the subqueries
|
|
* @param {document} obj
|
|
* @param {query[]} query
|
|
* @return {boolean}
|
|
*/
|
|
$and: (obj, query) => {
|
|
if (!Array.isArray(query)) throw new Error('$and operator used without an array')
|
|
|
|
for (let i = 0; i < query.length; i += 1) {
|
|
if (!match(obj, query[i])) return false
|
|
}
|
|
|
|
return true
|
|
},
|
|
/**
|
|
* Inverted match of the query
|
|
* @param {document} obj
|
|
* @param {query} query
|
|
* @return {boolean}
|
|
*/
|
|
$not: (obj, query) => !match(obj, query),
|
|
|
|
/**
|
|
* @callback whereCallback
|
|
* @param {document} obj
|
|
* @return {boolean}
|
|
*/
|
|
|
|
/**
|
|
* Use a function to match
|
|
* @param {document} obj
|
|
* @param {whereCallback} fn
|
|
* @return {boolean}
|
|
*/
|
|
$where: (obj, fn) => {
|
|
if (typeof fn !== 'function') throw new Error('$where operator used without a function')
|
|
|
|
const result = fn.call(obj)
|
|
if (typeof result !== 'boolean') throw new Error('$where function must return boolean')
|
|
|
|
return result
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Tell if a given document matches a query
|
|
* @param {document} obj Document to check
|
|
* @param {query} query
|
|
* @return {boolean}
|
|
* @alias module:model.match
|
|
*/
|
|
const match = (obj, query) => {
|
|
// Primitive query against a primitive type
|
|
// This is a bit of a hack since we construct an object with an arbitrary key only to dereference it later
|
|
// But I don't have time for a cleaner implementation now
|
|
if (isPrimitiveType(obj) || isPrimitiveType(query)) return matchQueryPart({ needAKey: obj }, 'needAKey', query)
|
|
|
|
// Normal query
|
|
for (const queryKey in query) {
|
|
if (Object.prototype.hasOwnProperty.call(query, queryKey)) {
|
|
const queryValue = query[queryKey]
|
|
if (queryKey[0] === '$') {
|
|
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
|
|
* @param {object} obj
|
|
* @param {string} queryKey
|
|
* @param {*} queryValue
|
|
* @param {boolean} [treatObjAsValue=false]
|
|
* @return {boolean}
|
|
* @private
|
|
*/
|
|
function matchQueryPart (obj, queryKey, queryValue, treatObjAsValue) {
|
|
const objValue = getDotValue(obj, queryKey)
|
|
|
|
// Check if the value is an array if we don't force a treatment as value
|
|
if (Array.isArray(objValue) && !treatObjAsValue) {
|
|
// If the queryValue is an array, try to perform an exact match
|
|
if (Array.isArray(queryValue)) return matchQueryPart(obj, queryKey, queryValue, true)
|
|
|
|
// Check if we are using an array-specific comparison function
|
|
if (queryValue !== null && typeof queryValue === 'object' && !isRegExp(queryValue)) {
|
|
for (const key in queryValue) {
|
|
if (Object.prototype.hasOwnProperty.call(queryValue, key) && arrayComparisonFunctions[key]) { 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 (const el of objValue) {
|
|
if (matchQueryPart({ k: el }, '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' && !isRegExp(queryValue) && !Array.isArray(queryValue)) {
|
|
const keys = Object.keys(queryValue)
|
|
const firstChars = keys.map(item => item[0])
|
|
const dollarFirstChars = firstChars.filter(c => 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 (const key of keys) {
|
|
if (!comparisonFunctions[key]) throw new Error(`Unknown comparison function ${key}`)
|
|
|
|
if (!comparisonFunctions[key](objValue, queryValue[key])) return false
|
|
}
|
|
return true
|
|
}
|
|
}
|
|
|
|
// Using regular expressions with basic querying
|
|
if (isRegExp(queryValue)) return comparisonFunctions.$regex(objValue, queryValue)
|
|
|
|
// queryValue is either a native value or a normal object
|
|
// Basic matching is possible
|
|
return areThingsEqual(objValue, queryValue)
|
|
}
|
|
|
|
// 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.getDotValues = getDotValues
|
|
module.exports.match = match
|
|
module.exports.areThingsEqual = areThingsEqual
|
|
module.exports.compareThings = compareThings
|
|
|