jsonmongoquery

Mongodb query and update operators for json object arrays.

Usage

import { queryToPredicate, updateToPredicate, context } from 'jsonmongoquery'

// Fix current date in a context
const context = new Context({ date: new Date() })

// Load some data
const data = [
  { _id: 1, item: { name: 'ab', code: '123' }, qty: 15, tags: ['A', 'B', 'C'] },
  { _id: 2, item: { name: 'cd', code: '123' }, qty: 20, tags: ['B'] },
  { _id: 3, item: { name: 'ij', code: '456' }, qty: 25, tags: ['A', 'B'] },
  { _id: 4, item: { name: 'xy', code: '456' }, qty: 30, tags: ['B', 'A'] },
  { _id: 5, item: { name: 'mn', code: '000' }, qty: 20, tags: [['A', 'B'], 'C'] }
]

// Query will select items where qty = 20
const filterQuery = { qty: { $eq: 20 } }
// Make an filter predicate function from the filter query, validate the query according to the query schema
const filterPredicate = queryToPredicate(filterQuery, { validate: true, context })
// Filter the data according to the predicate
const filtered = data.filter(filterPredicate)
console.log(filtered)

// Query will remove the last item from the tags array
const updateQuery = { $pop: { tags: 1 } }
// Make an update predicate function from the update query, validate the query according to the update schema
const updatePredicate = updateToPredicate(updateQuery, { validate: true, context })
// Filter the data according to the predicate
const updated = filtered.filter(updatePredicate)
console.log(updated)

Supported operators

Comparison query operators

• $eq { field: { $eq: value } }, { field: value } Matches documents where the value of a field equals the specified value
• $gt { field: { $gt: value } } Selects those documents where the value of the specified field is greater than (i.e. >) the specified value
• $gte { field: { $gte: value } } Selects the documents where the value of the specified field is greater than or equal to (i.e. >=) a specified value
• $in { field: { $in: [value1, ...] } } Selects the documents where the value of a field equals any value in the specified array
• $lt { field: { $lt: value } } Selects the documents where the value of the field is less than (i.e. <) the specified value
• $lte { field: { $lte: value } } Selects the documents where the value of the field is less than or equal to (i.e. <=) the specified value
• $ne { field: { $ne: value } } Selects the documents where the value of the specified field is not equal to the specified value. This includes documents that do not contain the specified field
• $nin { field: { $nin: [value1, ...] } } Selects the documents where the specified field value is not in the specified array or the specified field does not exist

Logical query operators

• $and { $and: [{ expression1 }, ...] } Performs a logical AND operation on an array of one or more expressions. Selects the documents that satisfy all the expressions.
• $not { field: { $not: { operator-expression } } } Performs a logical NOT operation on the specified operator-expression and selects the documents that do not match the operator-expression. This includes documents that do not contain the field.
• $nor { $nor: [{ expression1 }, ...] } Performs a logical NOR operation on an array of one or more query expression and selects the documents that fail all the query expressions in the array.
• $or { $or: [{ expression1 }, ...] } Performs a logical OR operation on an array of one or more expressions and selects the documents that satisfy at least one of the expressions.

Element query operators

• $exists { field: { $exists: boolean } } Matches documents that contain or do not contain a specified field, including documents where the field value is null
• $type { field: { $type: JSONType } } Selects documents where the value of the field is an instance of the specified JSON type(s)

Evaluation query operators

• $mod { field: { $mod: [divisor, remainder] } } Select documents where the value of a field divided by a divisor has the specified remainder
• $regex { field: { "$regex": "pattern", "$options": "options" } } Provides regular expression capabilities for pattern matching strings in queries
• $where { $where: "return true" } Pass a string containing a JavaScript expression

Array query operators

• $all { field: { $all: [ value1, ... valueN ] } } Selects the documents where the value of a field is an array that contains all the specified elements
• $elemMatch { field: { $elemMatch: { query1, ... queryN } } } Matches documents that contain an array field with at least one element that matches all the specified query criteria
• $size { field: { $size: number } } Matches any array with the number of elements specified by the argument

Field update operators

• $currentDate { $currentDate: { field1: true, field2: { $type: "date" }, field3: { $type: "timestamp" } }, ... } Sets the value of a field to the current date, either as a Date or a timestamp
• $inc { $inc: { field1: amount1, ... } } Increments a field by a specified value
• $min { $min: { field1: value1, ... } } Updates the value of the field to a specified value if the specified value is less than the current value of the field
• $max { $max: { field1: value1, ... } } Updates the value of the field to a specified value if the specified value is greater than the current value of the field
• $mul { $mul: { field1: number1, ... } } Multiply the value of a field by a number
• $rename {$rename: { field1: newName1, ... } } Updates the name of a field
• $set { $set: { field1: value1, ... } } Replaces the value of a field with the specified value
• $unset { $unset: { field1: "", ... } } Deletes a particular field

Array update operators

• $[] { update-operator: { "array.$[]": value } } Indicates that the update operator should modify all elements in the specified array field
• $addToSet { $addToSet: { field1: value1, ... } } Adds a value to an array unless the value is already present
• $pop { $pop: { field: -1 | 1, ... } } Removes the first or last element of an array
• $pull { $pull: { field1: value|condition, ... } } Removes from an existing array all instances of a value or values that match a specified condition
• $push { $push: { field1: value1, ... } } Appends a specified value to an array
• $each { $push: { field: { $each: [ value1, ... ] } }, $addToSet: { field: { $each: [ value1, ... ] } } } Modifier is available for use with the $addToSet operator and the $push operator.
• $position { $push: { field: { $each: [ value1, ... ], $position: num } } } Modifier specifies the location in the array at which the $push operator inserts elements
• $slice { $push: { field: { $each: [ value1, ... ], $slice: num } } } Modifier limits the number of array elements during a $push operation
• $sort { $push: { field: { $each: [ value1, ... ], $sort: -1 | 1 | { field1: 1, field2: -1, ... } } } Modifier orders the elements of an array during a $push operation
• $pushAll { $pullAll: { field1: [ value1, ... ], ... } } Removes all instances of the specified values from an existing array

Supported JSONTypes

A subset of BSON Types https://www.mongodb.com/docs/manual/reference/bson-types/#bson-types

| name | value | order | | ---- | ----- | ----- | | undefined | 0 | 0 | | null | 10 | 1 | | number | 1 | 2 | | string | 2 | 3 | | object | 3 | 4 | | array | 4 | 5 | | bool | 8 | 8 |

Notes

1. Lexicographic vs numeric order is not currently supported https://www.mongodb.com/docs/manual/reference/operator/update/#behavior
2. 100% unit test coverage, from the mongodb website examples, for each supported operator, for each supported type
3. Query intellisense support using typescript types
4. Query schemas and validation supplied
5. $where can be used as an update operator, $where: "this.title = this.title?.replace(/1 to 5/g, '1 to 10'); return true;"

Unsupported operators

Evaluation query operators

• $expr
• $jsonSchema
• $text

Geospatial query operators

• $geoIntersects
• $geoWithin
• $near
• $nearShere
• $box
• $center
• $centerSphere
• $geometry
• $maxDistance
• $minDistance
• $polygon

Bitwise query operators

• $bitsAllClear
• $bitsAllSet
• $bitsAnyClear
• $bitsAnySet

Projection operators

• $
• $elemMatch
• $slice

Miscellaneous query operators

• $comment
• $rand
• $natural

Field update operators

• $setOnInsert

Array update operators

• $
• $[]

Bitwise update operators

• $bit