📝Crypto

The module that handles encryption and decryption.

Imports

Service

import { CryptoService } from 'niro-health';

Module

import { CryptoModule } from 'niro-health';

Interface

import type { ICryptoService } from 'niro-health';

Environment Variables

name	description
CRYPTO_PASSWORD	Password used in the encryption and decryption process.

Write .env file with environment variable. Below has an example:

.env

CRYPTO_PASSWORD=o4t7bNT5CbOnlqBcah40R99zierzSQz3MS9Ssceqq2U=

Application Variables

name	values	description
crypto_driver	redis, sqlite, fs	The driver used for store metadata of encryption.

How to set variable

You can set the application variable in your main module and/or in the module that will inject the service.

import { Inject, Injectable } from '@nestjs/common';
import type { IConfigurationService } from 'niro-health';

@Injectable()
export class AppService {
  constructor(
    @Inject('IConfigurationService')
    private readonly configurationService: IConfigurationService,
  ) {
  this.initialize();
}

  async initialize() {
    return this.configurationService.setVariable('crypto_driver', 'redis');
  }
}

Method of Use

To use this module, you need to inject it into the desired service.

import { Module } from '@nestjs/common';
import {
  CryptoService,
  ConfigurationService,
  ValidatorRegexpService,
  StringExService,
  RedisService,
  DebugService,
  SqliteService,
  RandomService,
} from 'niro-health';
import { AppController } from './app.controller';
import { AppService } from './app.service';

@Module({
  controllers: [AppController],
  providers: [
    AppService,
    {
      provide: 'ICryptoService',
      useClass: CryptoService,
    },
    {
      provide: 'IConfigurationService',
      useClass: ConfigurationService,
    },
    {
      provide: 'IValidatorRegexpService',
      useClass: ValidatorRegexpService,
    },
    {
      provide: 'IStringExService',
      useClass: StringExService,
    },
    {
      provide: 'IRedisService',
      useClass: RedisService,
    },
    {
      provide: 'IDebugService',
      useClass: DebugService,
    },
    {
      provide: 'ISqliteService',
      useClass: SqliteService,
    },
    {
      provide: 'IRandomService',
      useClass: RandomService,
    },
  ],
})
export class AppModule {}

Injecting the module into our service.

import { Inject, Injectable } from '@nestjs/common';
import type { ICryptoService } from 'niro-health';

@Injectable()
export class AppService {
  constructor(
    @Inject('ICryptoService')
    private readonly cryptoService: ICryptoService,
  ) {}

  async encrypt() {
    return await this.cryptoService.encrypt('Hello World');
  }
}

With dependencies

You will need to inject the following interfaces.

Interface	Service
IConfigurationService	Link to Service documentation
IValidatorRegexpService	Link to Service documentation
IStringExService	Link to Service documentation
IRedisService	Link to Service documentation
IDebugService	Link to Service documentation
ISqliteService	Link to Service documentation
IRandomService	Link to Service documentation

Properties

Property	Scope	Description
get _driver	private	The driver used to store the metadata of encryption.
get _isRedis	private	Check if the driver is Redis.
get _isSqlite	private	Check if the driver is SQLite.
get _isFileSystem	private	Check if the driver is FileSystem.
get _fileSystemPath	private	Returns the path of the file in disk of the FileSystem.
get _fileSystemExistsData	private	Check if the file exists in disk of the FileSystem.
get _fileSystemEncode	private	Returns the encode of the file in disk of the FileSystem.

Methods

Method	Scope	Description
_createTable	private	It create the table in the SQLite database.
_fileSystemWrite	private	It writes the data in the file in disk of the FileSystem.
_fileSystemRead	private	It reads the data in the file in disk of the FileSystem.
_fileSystemDataParse	private	It parses the data in the file in disk of the FileSystem.
_createFileSystem	private	It creates the file in disk of the FileSystem.
_fileSystemAppend	private	It append data in the file in disk of the FileSystem.
_fileSystemFind	private	It finds a key in the file in disk of the FileSystem.
_fileSystemDelete	private	It deletes a key in the file in disk of the FileSystem.
_insert	private	It inserts a key and a value in the SQLite database.
_find	private	It find a key in the SQLite database.
_del	private	It deletes a key from the database.
_createHash	private	It takes a string, creates a hash of it, and returns the first 32 characters of the hash.
_getHash	private	It creates a hash of a random string.
_serialize	private	It takes a string, hashes it, and returns the hash.
_compress	private	It takes a value of type T, converts it to a string, compresses it, and returns the compressed string.
_decompress	private	It takes a string, decompresses it, and returns the result as a generic type.
_save	private	It saves a value to the cache.
_saveBuffer	private	It saves a buffer to the cache.
_load	private	It loads a value from the cache, decompresses it, and returns it.
_loadBuffer	private	It loads a buffer from the cache.
_delete	private	It takes a variable number of strings, serializes them, and then passes them to the Redis client's del function.
encrypt	public	It encrypts a string using a password and saves the encrypted string, the initialization vector, and the authentication tag to the database.
decrypt	public	It decrypts the encrypted string using the password and the IV and the tag.