Query Builder

!Build status

Validate AIS-conformant query trees and serialise them as SQL strings.

``ts
import createQueryBuilder from '@peak-ai/query-builder';
import * as moment from 'moment';

const fieldMetadata = {
associationTypeFieldName: 'associationtype',
associationRankFieldName: 'associationrank',
};

const fieldOptions = [
{
name: 'useremail',
type: 'large',
},
{
name: 'ordercount',
type: 'integer',
},
{
name: 'customergender',
type: 'small',
},
];

const query = {
id: '1',
combinator: 'and',
rules: [
{
id: '1',
field: 'useremail',
value: 'joebloggs@gmail.com',
operator: '=',
},
{
id: '2',
combinator: 'or',
rules: [
{
id: '2',
field: 'ordercount',
value: '20',
operator: '>',
},
{
id: '3',
field: 'customergender',
value: 'male',
operator: '=',
},
],
},
],
};

const dateFormatter = (date: Date) => moment(date).format('YYYY-MM-DD');
const queryBuilder = createQueryBuilder({ dateFormatter });

console.log(queryBuilder.where(query, fieldOptions, fieldMetadata));
// => (useremail = 'joebloggs@gmail.com' AND (ordercount > 20 OR customergender = 'male'))
`

Getting started

You can install Query Builder from npm:

`sh
npm i -E @peak-ai/query-builder
`

The library comprises of a factory function, exposed via a default binding, as well as an additional binding for the Mode enum and operator bindings:

`ts
import createQueryBuilder, { Mode, operators } from '@peak-ai/query-builder';
`

If you're using CommonJS, this means you'll have to destructure and rename the default binding:

`ts
const { default: createQueryBuilder, Mode, operators } = require('@peak-ai/query-builder');
`

API

$3

`ts
const queryBuilder = createQueryBuilder({
dateFormatter: (date: Date) => moment(date).format('YYYY-MM-DD'),
mode: Mode.Display,
operators: operators.sql,
});
`

Creates a query builder API surface for the given options.

#### Arguments

* options: BuilderOptions: an object containing:
* dateFormatter: (date: Date) => string: a function for converting dates to strings, the return value of which is used directly by the query builder
* mode: Mode (optional, defaulting to Mode.Validation): determines how the query builder should handle invalid query trees (missing values, no top-level rules etc.):
* Mode.Display: doesn't throw when the tree is deemed invalid, instead rendering fallback values within the rendered SQL strings
* Mode.Validation: explicitly throws an error when the query tree is deemed invalid
* operators: Operators (optional, defaulting to operators.sql): specifies the operators from which the queries are built:
* operators.sql: maps the rule operators to sql operators
* operators.recommender: maps the rule operators to python operators, typically used for interactions with recommenders

#### Returns

QueryBuilder: a query builder API surface

$3

`ts
queryBuilder.where(query, fieldOptions, fieldMetadata);
`

Builds, optionally validates, and returns an SQL string for the given query tree, intended to be used in an SQL WHERE clause.

#### Arguments

* query: RootQuery: a tree representing your SQL query. See the example at the beginning of the README
* fieldOptions: FieldOption[]: an array of objects containing the names and data types of all the possible fields that can be queried. See the example at the beginning of the README
* fieldMetadata: FieldMetadata: an object containing the column names of association fields:
* associationTypeFieldName: string: the column name of the association type field
* associationRankFieldName: string: the column name of the association rank field

#### Returns

string: an SQL-compliant WHERE clause

Local development

Prerequisites:

* Node Version Manager
* Yarn v1

1. Fork this repo
2. git clone
3. cd query-builder
4. nvm i
5. yarn

You can then run:

* yarn lint: runs ESLint against the source code
* yarn format: fixes and overwrites any source files that _don't_ adhere to our Prettier config
* yarn format:check: checks the formatting of our source files and fails if any don't adhere to said config, for CI and prepublish purposes
* yarn build: runs the TypeScript compiler against the project and produces distributable output
* yarn test: runs the unit tests
* yarn test:dist`: runs the compiled unit tests against the compiled source. Typically used by our pre-commit hook, CI, and pre-publish script

Contributing

Given this library is rather specific to our commercial requirements, we can't accept any contributions that change the _behaviour_ of the library. However, any contributions that may improve the underlying implementation (e.g. maintainability, performance etc.) will be considered given the test suite continues to pass. Please see the contribution guidelines for more info.