Event Manager Backend (event-manager-backend)

Welcome to Event Manager Backend (event-manager-backend)

Table of contents

• Introduction
• Requirements
• Installation
• Configuration
• Troubleshooting & FAQ

Introduction

The service is based on Strapi JS framework.

Requirements

• CPU cores >= 1
• RAM >= 256MB
• Git 2.*
• Docker 20.*

Installation

• Set up git to have ssh access to the repository
• Clone the source into local machine

$ git clone git@github.com:dasmeta/event-manager-backend.git

• Go to the project source $ cd event-manager-backend
• Run make with prefered configuration to start development environment.
• Run docker build to create a production ready image and install project dependencies.

$ docker build -t event-manager-backend:latest .

Configuration

• Create an environment file .env and defined variables

# Web Server
HOST=0.0.0.0
PORT=1337
SERVE_ADMIN_PANEL=

# Database

# mongo
DATABASE_CLIENT=mongo
DATABASE_URL=mongodb://strapi:strapi@mongo/strapi?authSource=admin
// or
DATABASE_HOST=strapi
DATABASE_USERNAME=strapi
DATABASE_PASSWORD=strapi
DATABASE_NAME=strapi
AUTHENTICATION_DATABASE=admin

# postgres
DATABASE_CLIENT=postgres
DATABASE_HOST=postgres
DATABASE_USERNAME=strapi
DATABASE_PASSWORD=strapi
DATABASE_NAME=strapi

# JWT settings to validate token
JWT_SECRET=
JWT_ALGORITHM="HS256"

# Centralized Authentication
AUTHENTICATION_SERVICE_API_HOST=
AUTHENTICATION_IS_LIVE_MODE=

# For aws lambda with sns trigger
MQ_CLIENT_NAME=SNS
AWS_REGION=
AWS_ACCESS_KEY_ID=
AWS_SECRET_ACCESS_KEY=

• Create and start a container ready to handle connections

$ make up-with-mongo 
$ make up-with-postgres

• The service will be accessible on http://0.0.0.0:8037

If data retention following env variables should be defined

ENABLE_CRON=true
DATA_RETENTION_DAYS=40 // event that are created more than 40 days ago will be remove, but only those which have 100% success
DATA_CLEANUP_HOUR=04 // time in a day on which cleanup job will be executed, in UTC and 24 hour format 

Troubleshooting & FAQ

• View service logs

$ docker logs -f --since 2m em-backend

• Run tests

$ docker exec em-backend bash -c "yarn test"

pubSub

Extended event publishing PubSub/Kafka package.

yarn add @dasmeta/event-manager-node-api

start local pub/sub

$ gcloud beta emulators pubsub start $ DATASTORE_EMULATOR_HOST=localhost:8432 DATASTORE_PROJECT_ID=YOUR_GCLOUD_PROJECT_ID gcloud beta emulators datastore start

example1.js

const { registerSubscriber, publish } = require("@dasmeta/event-manager-node-api");

async function test1(data) {
    console.log("test1", data);
}

async function test2(data) {
    console.log("test2", data);
}

async function test3(data) {
    console.log("test3", data);
}

registerSubscriber("dev.test", "dev-test_test1", test1);
registerSubscriber("dev.test", "dev-test_test2", test2);
registerSubscriber("dev.test.other", "dev-test_test3", test3);

setInterval(async () => {
    await publish("dev.test", { key: Date.now() });
}, 300);

setInterval(async () => {
    await publish("dev.test.other", { key2: Date.now() });
}, 500);

PUBSUB_EMULATOR_HOST="localhost:8085" PUBSUB_PROJECT_ID="YOUR_GCLOUD_PROJECT_ID" GCLOUD_PROJECT="YOUR_GCLOUD_PROJECT_ID" node example1.js

example2.js

const { publish, subscribeMulti } = require("@dasmeta/event-manager-node-api");


function subscribe1() {
    subscribeMulti("test", ["dev.test", "dev.test.other"], async (topic, data) => {
        console.log('\x1b[31m%s %s\x1b[0m', " 1 ", topic, data);
    });
}

function subscribe2() {
    // resubscribe
    subscribeMulti("test", ["dev.test"], async (topic, data) => {
        console.log('\x1b[32m%s %s\x1b[0m', " 2 ", topic, data);
    });

    subscribeMulti("test3", ["dev.test", "dev.test.other"], async (topic, data) => {
        console.log('\x1b[33m%s %s\x1b[0m', " 3 ", topic, data);
    });
}


setInterval(async () => {
    await publish("dev.test", { key: Date.now() });
}, 200);

setInterval(async () => {
    await publish("dev.test.other", { key2: Date.now() });
}, 300);

subscribe1();

setTimeout(async () => {
    subscribe2();
}, 20 * 1000);

PUBSUB_EMULATOR_HOST="localhost:8085" PUBSUB_PROJECT_ID="YOUR_GCLOUD_PROJECT_ID" GCLOUD_PROJECT="YOUR_GCLOUD_PROJECT_ID" node example2.js

example3.js

import { autoStart as AutoStart, subscribe as on, publish } from "@dasmeta/event-manager-node-api";

@AutoStart
class Example {
    @on("dev.test")
    async test1(data) {
        console.log("test1", data);
    }

    @on("dev.test")
    async test2(data) {
        console.log("test2", data);
    }

    @on("dev.test.other")
    async test3(data) {
        console.log("test3", data);
    }
}

setInterval(async () => {
    await publish("dev.test", { key: Date.now() });
}, 300);

setInterval(async () => {
    await publish("dev.test.other", { key2: Date.now() });
}, 500);

PUBSUB_EMULATOR_HOST="localhost:8085" PUBSUB_PROJECT_ID="YOUR_GCLOUD_PROJECT_ID" GCLOUD_PROJECT="YOUR_GCLOUD_PROJECT_ID" node example3.js

Kafka : run all examples with env variables

MQ_CLIENT_NAME='Kafka' KAFKA_BROKERS='127.0.0.1:29092'

PubSub : run all examples with env variables

PUBSUB_EMULATOR_HOST="localhost:8085" PUBSUB_PROJECT_ID="YOUR_GCLOUD_PROJECT_ID" GCLOUD_PROJECT="YOUR_GCLOUD_PROJECT_ID"