genericQuery.js

/* eslint-disable class-methods-use-this */
import Joi from 'joi';

/**
 *  ENUM TYPES
 */
const OperationType = {
  EQUALS: 'EQUALS',
  NOT_EQUALS: 'NOT_EQUALS',
  NOT_INCLUDED: 'NOT_INCLUDED',
  REGEX: 'REGEX',
  GREATER: 'GREATER',
  LOWER: 'LOWER',
  GREATER_OR_EQUAL: 'GREATER_OR_EQUAL',
  LOWER_OR_EQUAL: 'LOWER_OR_EQUAL',
  RANGE: 'RANGE',
};

const RelationType = {
  AND: 'AND',
  OR: 'OR',
};

/**
 * ENTITY SCHEMAS
 */
const GenericQueryItemSchema = Joi.object().keys({
  field: Joi.string(),
  operation: Joi.string().valid(Object.keys(OperationType)),
  value: Joi.any(),
});

const GenericQuerySchema = {
  relation: Joi.string().valid(Object.keys(RelationType)),
  items: Joi.alternatives().try(
    GenericQueryItemSchema,
    Joi.lazy(() => GenericQuerySchema), // recursive schema check
  ),
};

/**
 * GenericQuery class definition
 */
class GenericQuery {
  // relation = RelationType.AND;
  // items = [];
  GenericQuery(stringQuery) {
    try {
      const { relation, items } = JSON.parse(stringQuery);
      this.relation = relation;
      this.items = items;
    } catch (e) {
      throw new Error(`invalid string query provided ${e.message}`);
    }
  }

  toKnex() {
    // should build and return a knex query
    // will be used by objection models mostly
  }
}


const query = {
  relation: 'AND',
  items: [{
    field: 'name',
    operation: 'EQUALS',
    value: 'test',
  }, {
    field: 'date',
    operation: 'RANGE',
    value: {
      from: '',
      to: '',
    },
  }],
};

const stringQuery = JSON.stringify(query);

console.log(new GenericQuery(stringQuery));