Streaming Client

Sample GraphQL Streaming client for the Oracle Hospitality Integration Platform (OHIP) Streaming API.

• Streaming Client
  • Features
  • Installation
  • Configuration
  • Run
  • To-do

Features

• Load connection/stream parameters from environment variables
• Automatic refresh of OAuth tokens every 59 minutes
• Automatic reconnection in case of network intermittent errors or server failures
• Support for subscription parameters: chain, hotelId, offset (partial only) and delta.

Installation

• Install node:

  To easily install multiple versions of node locally, it is recommended to first install node version manager (nvm) and then install the require version as following:

  NODE_VERSION=18.11.0
  nvm install $NODE_VERSION
  nvm alias default $NODE_VERSION
  nvm use default #to set this version of node as default in your environment
  nvm use #to set the node version based on the .nvmrc file

  the above assumes you've installed nvm as described here, including [this step](this step: https://github.com/nvm-sh/nvm#nvmrc).

• Install the node modules used in the project:

  npm install typescript

  All other dependencies are installed via npm

  npm install

Configuration

Before running the application all required environment variables.

• If testing locally, variables can be added to an .env file

touch .env

• Set environment variables as following:

# OHIP gateway URL from OHIP dev portal environment
APIGW_URL=
# OHIP websocket gateway URL. Normally similar to API GW but with WS protocol
WS_URL=
# Endpoints
OAUTH_ENDPOINT=/oauth/v1/tokens
SUBS_ENDPOINT=/subscriptions
# OHIP dev portal app key
APP_KEY=
# SSD integration username/password
INTEGRATION_USER=
INTEGRATION_PASSWORD=
# OHIP dev portal environment credentials
CLIENT_ID=
CLIENT_SECRET=
# OAuth token expiry timeframe. Required to refresh token before it expires and connection is interrupted
TOKEN_EXPIRY=3540000
# Frequency to ping server
PING=10000
# OPERA Cloud chain for the subscription. Can be obtained from the app subscription in dev portal
CHAIN=
# (Optional) Enter a property Id to filter events generated only in that property
# HOTELID=
# (Optional) Enter value if to stream events from a given offset. Default is 0 (meaning all prior events up to 7 days all wil be streamed)
# OFFSET=0
# (Optional) Enter true to omit old and new values which are similar. Default is false
# DELTA=true
# Log level options: silly, trace, debug, info, warn, error, fatal
LOGLEVEL=debug
# Set Stats. true or false. Default is false.
STATS=true
# Stat bucket: HOUR, MINUTE (default) or SECOND. If not set time bucket won't be displayed, only summary.
TIME_BUCKET=SECOND

Run

Once all required environment variables have been set, project can be run by executing:

npm start

To run in development mode, execute

npm run dev

To-do

The following features are in the backlog of this project:

• Packaged as a container with multiple deployment options (docker compose and kubernetes)
• Pluggable target transports such as Console (currently only one supported), REST endpoint, database
• Unit tests