dns-setting/db.js

dns management: query, modify, shield corresponding domain name resolution

'use strict';

var s3 = require('sqlite3');
var fs = require('fs');

const dbp = "./db";
const sqlite3 = s3.verbose();
const dbName = `${dbp}/dns.db`;
function read(src) {
  try {
    return fs.readFileSync(src).toString();
  } catch (error) {
    console.error("read file error", src);
    return null;
  }
}
function hook(fun) {
  const db = new sqlite3.Database(dbName);
  let r = new Promise((res, rej) => fun(db, res, rej));
  db.close();
  return r;
}
function serialize() {
  try {
    fs.rmSync(dbName);
  } catch (e) {}
  hook((db) => {
    db.serialize(() => {
      db.exec(read(`${dbp}/serialize.sql`));
    });
  });
}
const evmt = process.env;
if (evmt.serialize) {
  serialize();
}
function getWhere(data, not = []) {
  let keyList = Object.keys(data);
  let result = {};
  let where = keyList
    .flatMap((k) => {
      if (not.includes(k) || (data[k] ?? null) === null) {
        return [];
      }
      if (/Like$/.test(k)) {
        result[`\$${k}`] = "%" + data[k] + "%";
        return `${k.replace(/Like$/, "")} like \$${k}`;
      }
      result[`\$${k}`] = data[k];
      return `${k} = \$${k}`;
    })
    .join(" and ");
  if (where) {
    where = `where ${where}`;
  }
  return { where, data: result };
}
function getSet(data, not = []) {
  let keyList = Object.keys(data);
  let result = {};
  let str = keyList
    .flatMap((k) => {
      if (not.includes(k) || (data[k] ?? null) === null) {
        return [];
      }
      result[`\$${k}`] = data[k];
      return `${k} = \$${k}`;
    })
    .join(" , ");
  if (str) {
    str = `SET ${str}`;
  }
  return { set: str, data: result };
}
function all(query, data) {
  return hook((db, res, rej) => {
    db.all(query.trim(), data, function (error, rows) {
      if (error) rej(error);
      else res(rows);
    });
  });
}
function tableList(name, match) {
  if ((match.isUsing ?? null) !== null) match.isUsing = match.isUsing ? 1 : 0;
  let { where, data } = getWhere(match);
  let query = `SELECT * FROM ${name} ${where}`;
  return all(query, data);
}
function updateItem(name, id, info) {
  if (info.isUsing ?? null === null) info.isUsing = 1;
  info.isUsing = info.isUsing ? 1 : 0;
  let { set, data } = getSet({ ...info });
  let query = `UPDATE ${name} ${set} where id = $id`;
  return hook((db, res, rej) => {
    db.run(query, { ...data, $id: id }, function (error) {
      if (error) rej(error);
      res();
    });
  });
}
function getInsert(info) {
  if (info.isUsing ?? null === null) info.isUsing = 1;
  info.isUsing = info.isUsing ? 1 : 0;
  let key = Object.keys(info);
  let key2 = key.map((k) => `\$${k}`);
  let data = Object.fromEntries(key2.map((k, i) => [k, info[key[i]]]));
  return { key, key1: key, key2, data };
}
function insertItem(name, info) {
  let { key1, key2, data } = getInsert({ ...info });
  let query = `INSERT INTO ${name} (${key1}) VALUES (${key2})`;
  return hook((db, res, rej) => {
    db.run(query, { ...data }, function (error, data) {
      if (error) rej(error);
      db.get(`select last_insert_rowid() as id from ${name} LIMIT 1;`, function (error, data) {
        if (error) rej(error);
        res(data.id);
      });
    });
  });
}
function deleteItem(name, id) {
  let query = `DELETE FROM ${name}  WHERE id = $id`;
  return hook((db, res, rej) => {
    db.run(query, { $id: id }, function (error, data) {
      if (error) rej(error);
      res(data);
    });
  });
}

exports.deleteItem = deleteItem;
exports.insertItem = insertItem;
exports.tableList = tableList;
exports.updateItem = updateItem;