EventLog Microservice Client Library for Node.js / ES2017 V2

This is a Node.js client library for service-eventlog2-node microservice. It provides an easy to use abstraction over communication protocols:

• HTTP/REST client
• Direct client for monolythic deployments
• Null client to be used in testing

Quick Links:

• Development
• Download
• Configure
• Run
• Use
• Source Documentation

Develop

Environment Setup

This is a Node.js project and you have to install Node.js tools. You can download them from official Node.js website: https://nodejs.org/en/download/

After node is installed you can check it by running the following command:

node -version

Then you need to configure node tools:

# Install typescript compiler
npm install typescript -g

# Install mocha test runner
npm install mocha -g

To work with GitHub code repository you need to install Git from: https://git-scm.com/downloads

Installing

After your environment is ready you can check out microservice source code from the Github repository:

git clone [email protected]:entinco/eic-services-infrastructure2.git

Then go to the project folder and install dependent modules:

# Install dependencies
npm install

If you worked with the client library before you can check out latest changes and update the dependencies:

# Update source code updates from github
git pull

# Update dependencies
npm update

Building

This client library is written in TypeScript language which is transcompiled into JavaScript. So, if you make changes to the source code you need to compile it before running or committing to github. The process will output compiled javascript files into /bin folder.

tsc

When you do continuous edit-build-test cycle, you can run typescript compiler with --watch option to detect and compile changes you make automatically:

tsc --watch

Testing

Unless you have to do something special, you don't need to worry about configuring and running the microservice. The tests are designed to do that task automatically.

Command to run unit tests:

npm test

You can also execute benchmarks as:

npm run benchmark

Download

Add dependency to the client library into package.json file of your project

{
    ...
    "dependencies": {
        ....
        "client-eventlog2-node": "^1.0.*",
        ...
    }
}

Then install the dependency using npm tool

# Install new dependencies
npm install

# Update already installed dependencies
npm update

Configure

Configuration for this module is stored in the following section:

---
# Client configuration
client-eventlog2-node:
  connection:
    protocol: http
    host: localhost
    port: 8080

Run

If you need to access the microservice directly, you can start the client SDK by defining package.json file:

{
    ...
    "scripts": {
        ...
        "start": "node ./bin/main.js"
    }
}

Use

Inside your code get the reference to the client library

var sdk = new require("client-eventlog2-node");

Define client configuration parameters that match configuration of the microservice external API

// Client configuration
var config = {
  connection: {
    protocol: "http",
    host: "localhost",
    port: 8080,
  },
};

Instantiate the client and open connection to the microservice

// Create the client instance
var client = sdk.EventLogHttpClientV1(config);

// Connect to the microservice
try {
    await client.open(null);
    // Work with the microservice
    ...
} catch(err) {
    console.error('Connection to the microservice failed');
    console.error(err);
}

Now the client is ready to perform operations

// Log system event
let event = await client.logEvent(null, {
  type: "restart",
  source: "server 1",
  message: "Server restarted",
});

var now = new Date();

// Get the list system events
let page = await client.getEvents(
  null,
  {
    from: new Date(now.getTime() - 24 * 3600 * 1000),
    to: now,
    source: "server 1",
  },
  {
    total: true,
    skip: 0,
    take: 100,
  }
);

Contract

The contract for this microservice is:

var descriptor = {
    "example", "persistence", "memory", "*", "1.0"
}

Acknowledgements

This client library was created by Sergey Seroukhov and is currently maintained by Danylo Kuznetsov.