lemon-engine

Automatic Node Synchronizer between DynamoDB + Redis + Elasticsearch over AWS Cloud.

• NOTE 백엔드 서버에 lemon-backend-api 별도 실행 필요!

Overview

• NoSQL (DynamoDB) <-> ElastiSearch <-> Redis 데이터 동기화
• DynamoDB 업데이트시 -> 업데이트 Stream 수신 -> 변경 데이터 추적 -> ES 와 동기화.

Usage (사용법)

• install with npm npm install lemon-engine --save

• create internal Service with data model

import engine from 'lemon-engine';
 
//! create engine in global scope.
const $engine = engine(global, { env: process.env });
 
// deefine properties.
const FIELDS = [
    'id', 'type', 'parent', 'name', ...
];
const ES_FIELDS = FIELDS;
 
//! config engines (as example)
const $model = $engine.createModel(`${name}`, {
    ID_TYPE         : '#STRING',        // WARN! '#' means no auto-generated id.
    ID_NEXT         : 0,                // ID Starts
    FIELDS          : FIELDS,           // Properties
    DYNA_TABLE      : 'LemonTable',     // DynamoDB Table
    REDIS_PKEY      : '#TDQ',           // '#' means no use redis, but elastic as cache.
    ES_INDEX        : 'lemons-v1',      // ES Index Name
    ES_TYPE         : 'none',           // ES Type Name (deprecated since ES6)
    ES_FIELDS       : ES_FIELDS,        // ES Fields List.
    NS_NAME         : name,             // Notify Service Name. (null means no notifications)
    ES_MASTER       : 1,                // ES Master NODE.
    ES_VERSION      : 6,                // ES Target Version (6 means 6.x)
    CLONEABLE       : true,             // Clonable with parent/cloned property.
    PARENT_IMUT     : false,            // Immutable of parent property (2018.03.15)
    ES_TIMESERIES   : false,            // As time-Series data, useful when saving time-series.
    XECURE_KEY      : 'lemon',          // (optional) Encryption Key (use '*' prefix at property name: ver 0.3.22)
});

• build CRUD common service functions.

//! search by param
// ex) { id: 1234 } => search by `id == 1234`.
const do_search = (id, param) => {
    _log(NS, `do_search(${id})... param=`, $U.json(param));
    return $model.do_search(id, param);
};

Installation (설치법)

• lemon-backend-api 백본 서비스 구성
• configure environment.

개발 (Development)

• TODO refer to lemon-hello-api

Deploy (NPM 모듈 배포)

1. package.json 의 version 정보를 변경
2. $ npm run publish 실행 (단, npm 로그인 필요!)
3. lemon-engine 으로 배포됨.

Contribution

Plz, request PR. See CODE_OF_CONDUCT

LICENSE

MIT

---

VERSION INFO

Version	Description
2.2.5	improve http-request of type+id+cmd.
2.2.4	optimize log in init engine.
2.2.3	hot-fix type error of $U.dt().
2.2.2	relay context as that._ctx in on_record_update(), and use common BACKBONE_API env.
2.2.1	hot-fix error of $protocol().do_execute().
2.2.0	support enhanced type definitions.
2.1.8	support do_read_deep for direct reading via dynamodb.
2.1.6	support method PATCH in web-proxy. required backbone#2.1.4.
2.1.5	custom web-proxy by _$.createWebProxy().
2.1.4	support relaying headers in web-proxy. required backbone#2.1.3.
2.1.0	refactoring to typescript.
2.0.0	rename to lemon-engine, and set to public.