@justeat/f-stat-client

f-stat-client

Javascript HTTP client for publishing stats to ElasticSearch

---

This client abstracts away the complexity of publishing stats to ElasticSearch, such as API timings so you can then graph on these results. It also provides a standardised approach for to follow that can be used in a suite of features and components, allowing you to use and report in a generic way.

Benefits (Now)

• Simple publish method that hides away the complexities of making posts requests to ElasticSearch
• Sensible defaults, with the ability to override all
• If you run ElasticSearch locally in a Docker Container and use the host localhost then you can see you results instantly (see https://www.elastic.co/guide/en/elasticsearch/reference/7.0/docker.html & https://elasticvue.com/)
• Built-in mock ability by providing a mock on the constructor (see https://github.com/elastic/elasticsearch-js-mock and an example below)

Benefits (Soon)

• encapsulated batch publishing
• encapsulated sample publishing
• encapsulated authentication

---

Usage

Installation

Install the module using npm or Yarn:

yarn add @justeat/f-stat-client

Initialisation/Construction e.g.

import StatClient from '@justeat/f-stat-client';

const options = {
    statClientUri: 'http://public-elastic-search-endpoint',
    tenant: 'uk',
    featureName: 'checkoutweb'
};

const client = new StatClient(options);

How to use

await client.publish({ verb: 'GET', segment: '/search', status: 200, timing: 611 });

Note; the dynamic model passed to the publish() method will get deconstructed and written out as individual fields on the ElasticSearch document along with the fixed fields of FeatureName, Tenant and a Timestamp.

An example of the final document written to ElasticSearch:

Constructor

Parameter	Description	Type	Example
options	The overrides for the default options	json [string]	{statClientUri: 'http://localhost:9200',tenant: 'ns',featureName: 'Generic Front End'}(See below the defaults for the options if not overridden via the constructor options)
mock	This can be supplied for testing purposes and will be used to return your mock response instead	@elastic/elasticsearch-mock	(see mock example below)

---

Options

Parameter	Description	Type	Default
statClientUri	The host of the stat publishing endpoint	String	'http://localhost:9200'
tenant	This is a key identifier to group stats by country, e.g. uk	String	'ns'
featureName	This is a key identifier to group stats by feature, e.g. salesWebsite	String	'Generic Front End'
statClientUser	The username to gain access to the stat publishing endpoint (if not supplied then no authentication will be used)	String	null
statClientPwd	The password to gain access to the stat publishing endpoint (ignored if user not supplied)	String	null
statClientIndexName	This is index to write to	String	'justeat'

---

Client Methods

These are all of the methods exposed by the f-stat-client

Method	Description	Parameters	Example
publish	Sends a dynamic model (stat details) to the Endpoint	json [string]	{verb: 'GET',segment: '/search',status: 200,timing: 654}

## How to Test/Mock e.g.

---

import StatClient from '@justeat/f-stat-client';

const Mock = require('@elastic/elasticsearch-mock');

const mock = new Mock();

// Build a cut down mock reponse
const mockResponse = {
    _index: 'justeat',
    result: 'created',
    statusCode: 201
};

// Mock the action to return the mock response
mock.add({
    method: 'POST',
    path: '*'
}, () => (mockResponse));

const options = {
    statClientUri: 'http://localhost:9200',
    tenant: 'uk',
    featureName: 'checkoutweb_test',
    statClientIndexName: 'justeat'
};

// Supply the mock on the constructor
const client = new StatClient(options, mock);

// Act
const response = await client.publish({ verb: 'GET', segment: '/basket', status: 200, timimg: 654 });

// Assert
expect(response.body.result).toBe('created');

---