@naturalcycles/mysql-lib/dist/query.util.js

MySQL client implementing CommonDB interface

import { _hb } from '@naturalcycles/js-lib';
import { white, yellow } from '@naturalcycles/nodejs-lib/colors';
import * as mysql from 'mysql';
import { mapNameToMySQL } from './schema/mysql.schema.util.js';
const MAX_PACKET_SIZE = 1024 * 1024; // 1Mb
const MAX_ROW_SIZE = 800 * 1024; // 1Mb - margin
/**
 * Returns `null` if it detects that 0 rows will be returned,
 * e.g when `IN ()` (empty array) is used.
 */
export function dbQueryToSQLSelect(q) {
    const tokens = selectTokens(q);
    // filters
    const whereTokens = getWhereTokens(q);
    if (!whereTokens)
        return null;
    tokens.push(...whereTokens);
    // order
    tokens.push(...groupOrderTokens(q));
    // offset/limit
    tokens.push(...offsetLimitTokens(q));
    return tokens.join(' ');
}
/**
 * Returns null in "0 rows" case.
 */
export function dbQueryToSQLDelete(q) {
    const tokens = [`DELETE FROM`, mysql.escapeId(q.table)];
    // filters
    const whereTokens = getWhereTokens(q);
    if (!whereTokens)
        return null;
    tokens.push(...whereTokens);
    // offset/limit
    tokens.push(...offsetLimitTokens(q));
    return tokens.join(' ');
}
/**
 * Returns array of sql statements to respect the max sql size.
 */
export function insertSQL(table, rows, verb = 'INSERT', logger = console) {
    // INSERT INTO table_name (column1, column2, column3, ...)
    // VALUES (value1, value2, value3, ...);
    // eslint-disable-next-line unicorn/no-array-reduce
    const fieldSet = rows.reduce((set, row) => {
        for (const field of Object.keys(row)) {
            set.add(field);
        }
        return set;
    }, new Set());
    const fields = [...fieldSet];
    const start = [
        verb,
        `INTO`,
        mysql.escapeId(table),
        `(` + [...fields].map(f => mysql.escapeId(mapNameToMySQL(f))).join(',') + `)`,
        `VALUES\n`,
    ].join(' ');
    const valueRows = rows.map(rec => {
        return `(` + fields.map(k => mysql.escape(rec[k])).join(',') + `)`;
    });
    const full = start + valueRows.join(',\n');
    if (full.length < MAX_PACKET_SIZE)
        return [full];
    const sqls = [];
    let sql;
    for (const vrow of valueRows) {
        if (!sql) {
            sql = start + vrow;
        }
        else {
            if (sql.length + vrow.length >= MAX_ROW_SIZE) {
                sqls.push(sql);
                sql = start + vrow; // reset
            }
            else {
                sql += ',\n ' + vrow; // add
            }
        }
    }
    if (sql) {
        sqls.push(sql); // last one
    }
    logger.log(`${white(table)} large sql query (${yellow(_hb(full.length))}) was split into ${yellow(sqls.length)} chunks`);
    return sqls;
    // todo: handle "upsert" later
}
export function insertSQLSingle(table, record) {
    // INSERT INTO table_name (column1, column2, column3, ...)
    // VALUES (value1, value2, value3, ...);
    const tokens = [
        `INSERT INTO`,
        mysql.escapeId(table),
        `(` +
            Object.keys(record)
                .map(f => mysql.escapeId(mapNameToMySQL(f)))
                .join(',') +
            `)`,
        `\nVALUES`,
        `(` +
            Object.values(record)
                .map(v => mysql.escapeId(v))
                .join(',') +
            `)`,
    ];
    return tokens.join(' ');
}
export function insertSQLSetSingle(table, record) {
    return {
        sql: `INSERT INTO ${mysql.escapeId(table)} SET ?`,
        values: [record],
    };
}
export function dbQueryToSQLUpdate(q, patch) {
    // var sql = mysql.format('UPDATE posts SET modified = ? WHERE id = ?', [CURRENT_TIMESTAMP, 42]);
    const whereTokens = getWhereTokens(q);
    if (!whereTokens)
        return null;
    const tokens = [
        `UPDATE`,
        mysql.escapeId(q.table),
        `SET`,
        Object.keys(patch)
            .map(f => mysql.escapeId(mapNameToMySQL(f)) + ' = ?')
            .join(', '),
        ...whereTokens,
    ];
    return mysql.format(tokens.join(' '), Object.values(patch));
}
function selectTokens(q) {
    let fields = ['*'];
    if (q._selectedFieldNames) {
        fields = q._selectedFieldNames.length ? q._selectedFieldNames : ['id'];
    }
    // We don't do `escapeId` cause it'll ruin e.g SELECT `count *` FROM ...
    return [
        `SELECT`,
        q._distinct && 'DISTINCT',
        fields.map(f => mapNameToMySQL(f)).join(', '),
        `FROM`,
        mysql.escapeId(q.table),
    ].filter(Boolean);
}
function offsetLimitTokens(q) {
    const tokens = [];
    if (q._limitValue) {
        tokens.push(`LIMIT`, String(q._limitValue));
        // In SQL OFFSET is only allowed if LIMIT is set
        if (q._offsetValue) {
            tokens.push(`OFFSET`, String(q._offsetValue));
        }
    }
    return tokens;
}
function groupOrderTokens(q) {
    const t = [];
    if (q._groupByFieldNames?.length) {
        t.push(`GROUP BY`, q._groupByFieldNames.map(c => `\`${c}\``).join(', '));
    }
    if (q._orders.length) {
        t.push(`ORDER BY`, q._orders.map(o => `\`${o.name}\` ${o.descending ? 'DESC' : 'ASC'}`).join(', '));
    }
    return t;
}
const OP_MAP = {
    '==': '=',
};
/**
 * Returns `null` for "guaranteed 0 rows" cases.
 */
function getWhereTokens(q) {
    if (!q._filters.length)
        return [];
    let returnNull = false;
    const tokens = [
        `WHERE`,
        q._filters
            .map(f => {
            if (f.val === null || f.val === undefined) {
                // special treatment
                return [
                    mysql.escapeId(mapNameToMySQL(f.name)),
                    f.op === '==' ? 'IS NULL' : 'IS NOT NULL',
                ].join(' ');
            }
            if (Array.isArray(f.val)) {
                // special case for arrays
                if (!f.val.length)
                    returnNull = true;
                return `${mysql.escapeId(mapNameToMySQL(f.name))} IN (${mysql.escape(f.val)})`;
            }
            return [
                mysql.escapeId(mapNameToMySQL(f.name)),
                OP_MAP[f.op] || f.op,
                mysql.escape(f.val),
            ].join(' ');
        })
            .join(' AND '),
    ];
    if (returnNull)
        return null;
    return tokens;
}