miladezzat
Memoz
Memoz is an in-memory database that persists on disk, offering easy CRUD operations with a simple API. it supports document persistence to disk.
Installation
npm i memoz
# or
yarn add memozUsage
import { Memoz, FuzzySearchOptions } from "memoz";
interface IUser {
readonly id?: string;
name: string;
age: number;
}
const memoz = new Memoz<IUser>({
persistToDisk: true, // to allow persist data on disk - default false
storagePath: './data', // the location to persist data - default './data'
useMutex: true, // Whether to use a mutex for thread safety - default false
});
async function boot() {
// Uncomment to create and store users in the database
// const docs = Array.from({ length: 1000 }, (_, i) => ({ name: `User ${i}`, age: i }));
// await memoz.createMany(docs);
// Loop to get users with pagination and sorting to test caching
const totalPages = 2; // Define the total number of pages to iterate over
const usersPerPage = 10; // Number of users per page
for (let index = 0; index < totalPages; index++) {
try {
const users = await memoz
.getMany() // Retrieve all users
.sort([{ name: 'asc' }]) // Sort users by name in ascending order
.skip(index * usersPerPage) // Calculate the correct offset for pagination
.limit(usersPerPage); // Limit the number of users retrieved
console.log(`Page ${index + 1}:`, users); // Log the users for the current page
} catch (error) {
console.error(`Error retrieving users for page ${index + 1}:`, error); // Handle any errors
}
}
// support regex
const user = await memoz.getOne({
field: 'name',
operator: '$regex',
value: { $regex: '999', $options: 'i' }, // the $regex can be new RegExp
});
console.log(user);
{
const options: FuzzySearchOptions = {
maxDistance: 2,
scoringStrategy: 'default',
};
// Perform a fuzzy search
const results = await memoz.fuzzySearch('User 999', ['age', 'name'], options, 5);
console.log(results);
}
{
const options: FuzzySearchOptions = {
maxDistance: 2,
scoringStrategy: 'tokenCount',
fieldWeights: { title: 2, content: 1 }, // Title matches count more
};
// Perform a fuzzy search
const results = await memoz.fuzzySearch('User 999', ['age', 'name'], options);
console.log(results.slice(0, 2));
}
{
const customScoringFn = (token: string, fieldToken: string, distance: number, fieldWeight: number) => {
const baseScore = fieldWeight * (1 / (distance + 1)); // Decrease score as distance increases
const titleBonus = fieldToken.includes(token) ? 1 : 0; // Bonus if the fieldToken contains the token
return baseScore + titleBonus; // Total score
};
// Example usage
const options: FuzzySearchOptions = {
maxDistance: 2,
scoringStrategy: 'custom',
customScoringFn,
};
// Perform a fuzzy search
const results = await memoz.fuzzySearch('User 999', ['age', 'name'], options);
console.log(results.slice(0, 2));
}
}
// Start the boot process
boot();