lib/QueryBuilderBase.js
const Helpers = require('./Helpers');
const QueryParser = require('./QueryParser');
const State = require('./State');
class QueryBuilderBase {
/**
* @private
* @constructor
* @param {Driver} Driver - The syntax driver for the database
* @param {Adapter} Adapter - The database module adapter for running queries
*/
constructor (Driver, Adapter) {
this.driver = Driver;
this.adapter = Adapter;
this.parser = new QueryParser(this.driver);
this.state = new State();
}
_like (field, val, pos, like, conj) {
field = this.driver.quoteIdentifiers(field);
like = `${field} ${like} ?`;
if (pos === 'before') {
val = `%${val}`;
} else if (pos === 'after') {
val = `${val}%`;
} else {
val = `%${val}%`;
}
conj = (this.state.queryMap.length < 1) ? ' WHERE ' : ` ${conj} `;
this._appendMap(conj, like, 'like');
this.state.whereValues.push(val);
}
/**
* Append a clause to the query map
*
* @private
* @param {String} conjunction - linking keyword for the clause
* @param {String} string - pre-compiled sql fragment
* @param {String} type - type of sql clause
* @return {void}
*/
_appendMap (conjunction, string, type) {
this.state.queryMap.push({
type: type,
conjunction: conjunction,
string: string
});
}
/**
* Handle key/value pairs in an object the same way as individual arguments,
* when appending to state
*
* @private
* @param {mixed} letName Lorem Ipsum
* @param {mixed} valType Lorem Ipsum
* @param {mixed} key Lorem Ipsum
* @param {mixed} val Lorem Ipsum
* @return {Array} - modified state array
*/
_mixedSet (letName, valType, key, val) {
let obj = {};
if (Helpers.isScalar(key) && !Helpers.isUndefined(val)) {
// Convert key/val pair to a simple object
obj[key] = val;
} else if (Helpers.isScalar(key) && Helpers.isUndefined(val)) {
// If just a string for the key, and no value, create a simple object with duplicate key/val
obj[key] = key;
} else {
obj = key;
}
Object.keys(obj).forEach(k => {
// If a single value for the return
if (['key', 'value'].indexOf(valType) !== -1) {
const pushVal = (valType === 'key') ? k : obj[k];
this.state[letName].push(pushVal);
} else {
this.state[letName][k] = obj[k];
}
});
return this.state[letName];
}
_whereMixedSet (key, val) {
this.state.whereMap = [];
this.state.rawWhereValues = [];
this._mixedSet('whereMap', 'both', key, val);
this._mixedSet('rawWhereValues', 'value', key, val);
}
_fixConjunction (conj) {
const lastItem = this.state.queryMap[this.state.queryMap.length - 1];
const conjunctionList = Helpers.arrayPluck(this.state.queryMap, 'conjunction');
if (this.state.queryMap.length === 0 || (!Helpers.regexInArray(conjunctionList, /^ ?WHERE/i))) {
conj = ' WHERE ';
} else if (lastItem.type === 'groupStart') {
conj = '';
} else {
conj = ` ${conj} `;
}
return conj;
}
_where (key, val, defaultConj) {
// Normalize key and value and insert into this.state.whereMap
this._whereMixedSet(key, val);
// Parse the where condition to account for operators,
// functions, identifiers, and literal values
this.state = this.parser.parseWhere(this.driver, this.state);
this.state.whereMap.forEach(clause => {
const conj = this._fixConjunction(defaultConj);
this._appendMap(conj, clause, 'where');
});
this.state.whereMap = {};
}
_whereNull (field, stmt, conj) {
field = this.driver.quoteIdentifiers(field);
const item = `${field} ${stmt}`;
this._appendMap(this._fixConjunction(conj), item, 'whereNull');
}
_having (key, val = null, conj = 'AND') {
// Normalize key/val and put in state.whereMap
this._whereMixedSet(key, val);
// Parse the having condition to account for operators,
// functions, identifiers, and literal values
this.state = this.parser.parseWhere(this.driver, this.state);
this.state.whereMap.forEach(clause => {
// Put in the having map
this.state.havingMap.push({
conjunction: (this.state.havingMap.length > 0) ? ` ${conj} ` : ' HAVING ',
string: clause
});
});
// Clear the where Map
this.state.whereMap = {};
}
_whereIn (key, val, inClause, conj) {
key = this.driver.quoteIdentifiers(key);
const params = Array(val.length);
params.fill('?');
val.forEach(value => {
this.state.whereValues.push(value);
});
conj = (this.state.queryMap.length > 0) ? ` ${conj} ` : ' WHERE ';
const str = `${key} ${inClause} (${params.join(',')}) `;
this._appendMap(conj, str, 'whereIn');
}
_run (type, table, sql, vals) {
if (!sql) {
sql = this._compile(type, table);
}
if (!vals) {
vals = this.state.values.concat(this.state.whereValues);
}
// Reset the state so another query can be built
this._resetState();
// Pass the sql and values to the adapter to run on the database
return this.query(sql, vals);
}
_getCompile (type, table, reset) {
reset = reset || false;
const sql = this._compile(type, table);
if (reset) {
this._resetState();
}
return sql;
}
/**
* Complete the sql building based on the type provided
*
* @private
* @param {String} type - Type of SQL query
* @param {String} table - The table to run the query on
* @return {String} - The compiled sql
*/
_compile (type, table) {
// Put together the basic query
let sql = this._compileType(type, table);
// Set each subClause
['queryMap', 'groupString', 'orderString', 'havingMap'].forEach(clause => {
const param = this.state[clause];
if (!Helpers.isScalar(param)) {
Object.keys(param).forEach(part => {
sql += param[part].conjunction + param[part].string;
});
} else {
sql += param;
}
});
// Append the limit, if it exists
if (Helpers.isNumber(this.state.limit)) {
sql = this.driver.limit(sql, this.state.limit, this.state.offset);
}
return sql;
}
_compileType (type, table) {
let sql = '';
switch (type) {
case 'insert':
const params = Array(this.state.setArrayKeys.length).fill('?');
sql = `INSERT INTO ${table} (`;
sql += this.state.setArrayKeys.join(',');
sql += `) VALUES (${params.join(',')})`;
break;
case 'update':
sql = `UPDATE ${table} SET ${this.state.setString}`;
break;
case 'delete':
sql = `DELETE FROM ${table}`;
break;
default:
sql = `SELECT * FROM ${this.state.fromString}`;
// Set the select string
if (this.state.selectString.length > 0) {
// Replace the star with the selected fields
sql = sql.replace('*', this.state.selectString);
}
break;
}
return sql;
}
_resetState () {
this.state = new State();
}
}
module.exports = QueryBuilderBase;