MeghdutaJS

Meghduta is distributed in memory messaging service written in NodeJS. Meghduta literally means Cloud Messenger and we strive to be so. :)

Features

• [X] Unlimited number of Queues (limited only by RAM memory)
• [X] Unlimited number of Topics (limited only by RAM memory)
• [X] Auto create Queue or Topic if not exists already
• [X] Simple HTTP API for Queue operations (PUSH, PULL) and Topic operation (PUB)
• [X] Websocket API for Topic operations (PUB, SUB)
• [X] HA cluster - Shared
• [ ] HA cluster - Replicated
• [ ] Auto SSL

Install

>> npm install -g meghduta

see examples directory

Usage - Library package

see examples/start.js

Usage - STANDALONE Mode

>> meghduta

Is equivalent to

>> meghduta --httpPort 6600 --webSocketPort 6610

Usage - SHARED Mode

one.example.com >> meghduta-shared --httpPort 6600 --webSocketPort 6610 --servers http://two.example.com:8080

two.example.com >> meghduta-shared --httpPort 8080 --webSocketPort 8081 --servers http://one.example.com:6600

Usage - SHARED Mode (more than 2 Servers)

>> meghduta-shared --servers http://localhost:8080,http://localhost:9090

>> meghduta-shared --httpPort 8080 --webSocketPort 8081 --servers http://localhost:6600,http://localhost:9090

>> meghduta-shared --httpPort 9090 --webSocketPort 9091 --servers http://localhost:8080,http://localhost:6600

API

Target| Method | Port | URL | Request | Response ------|--------|------|---------------|----------------------------------------------------------------|---------------------| Queue | HTTP POST | 6600 | /meghduta/queue/push | { "queue" : "MY_QUEUE", "message" : "First message to be queued" }| 'Message queued' Queue | HTTP POST | 6600 | /meghduta/queue/pull | { "queue" : "MY_QUEUE" } | { "message : "First message to be queued" } | Topic | HTTP POST | 6600 |/meghduta/topic/publish | { "topic" : "MY_TOPIC", "message" : "First message to be published" } | 'Message published' Topic | WS Send | 6610 |/meghduta/topic | 'PUB MY_TOPIC Second message to be published' | Topic | WS Send | 6610 |/meghduta/topic | 'SUB MY_TOPIC' |

General Tips and Recommendation

• Don't use it in cluster mode with PM2, use HA Shared or Replicated mode instead
• HA cluster must be deployed behind load balancer
• Use keepAlive=true in http client when consuming HTTP API for best performance
• Use ZIP or LZ4 compression at client side for large message value
• Only Queue contents are SHARED or REPLICATED in HA mode, Topic PUB-SUB functionality remains same

License

Apache 2.0