DNA Center Assurance Event Handler

This repo is an example of how to write a simple event handler for DNA Center Assurance (Events and Health)

This sample is written as a simple Microservice which uses the Serverless Framework

Prerequisite

• Node.js 8+

Geting Started:

There are two modes in which this application can be run.

• Run locally in your network or
• On AWS Lambda

Steps:

Install Serverless Framework

npm install -g serverless

Clone this Repository

git clone https://github.com/CiscoDevNet/DnacEventHandler.git

Install nodejs dependencies

npm i

Local Development

sls offline start 

AWS Lambda Deployment

1. Setup AWS access key and secret key

In the command prompt of the shell

export AWS_ACCESS_KEY_ID=YOUR_ACCESS_KEY
export AWS_SECRET_ACCESS_KEY=YOUR_SECRET_ACCESS_KEY

2. Deployment

sls deploy        # deploy to AWS Lambda for the first time

or if it is already deployed:

sls deploy function -f app  # deploy code to AWS Lambda

3. Check Logs

sls logs -f app -t

Usage

Start the server using the command:

$ sls offline start

Serverless: Starting Offline: dev/ap-southeast-1.

Serverless: Routes for app:
Serverless: ANY /
Serverless: ANY /{proxy*}

Serverless: Offline listening on http://localhost:3000

The WebHook is now running port 3000

There are 2 endpoints that this service exposes:

1. /v1/rules (http://0.0.0.0:3000/v1/rules)
2. /v1/events (http://0.0.0.0:3000/v1/events)

Rules:

Rule are very simple instructions written in Javascript format. Use curl to send a POST req using the sample RULE provided for reference in the file https://github.com/CiscoDevNet/DnacEventHandler/blob/master/SampleRule.json

curl -H "Content-Type: application/json" -X POST --data @SampleRule.json http://0.0.0.0:3000/v1/rules

Rule will be evaluated in a context where this is the event passed to the rule for evaluation. Using this to reference a field in event, like:

• this.severity
• this.priority
• this.connectedDevice[0].hostname

Events:

You can simulate the event to your Webhook with curl using the sample Event provided for reference in the file https://github.com/CiscoDevNet/DnacEventHandler/blob/master/SampleEvent.json

curl -H "Content-Type: application/json" -X POST --data @SampleEvent.json http://0.0.0.0:3000/v1/events