logarithm

logarithm Is A Koa Middleware That Records Logs In ElasticSearch. The CLI binary also allows to execute commands on the ElasticSearch instance via the API, such as:

• creating snapshots,
• installing templates,
• etc

yarn add logarithm

Table Of Contents

• Table Of Contents
• API
• logarithm(options: !Config): !_goa.Middleware
  • Config
  • Hit
• async ping(url: string, timeout: number): void
• CLI
  • List Templates, -T
  • Statistics, -s
• Copyright & License

API

The package is available by importing its default function and a named function:

import logarithm, { ping } from 'logarithm'

logarithm(  options: !Config,): !_goa.Middleware

Creates a middleware for logging requests in Koa/Goa web-server and returns it.

• options* !Config: Options for the middleware.

Config: Options for the program.

/* yarn example/ */
import core from '@idio/idio'
import logarithm, { ping } from 'logarithm'

(async () => {
  await ping(process.env.ELASTIC)

  // setup for idio web-server
  const { url, app } = await core()

  app.use(logarithm({
    app: 'idio.cc',
    url: process.env.ELASTIC,
    index: 'clients',
  }))
  app.use(async (ctx) => {
    ctx.body = 'hello world'
  })
  console.log(url)
})()

The following data structure is sent to the server:

Hit: A record sent to ElasticSearch.

| Name | Type | Description | | ------------ | ---------------- | ------------------------------------------------- | | app* | string | The application name from the config. | | ip* | string | Client IP address. | | path* | string | The decoded request path. | | headers* | !Object | The request headers. | | status* | number | The status code. | | date* | !Date | The date of the request. | | method* | string | The method of the request, e.g., GET or POST. | | query | !Object | Possible query from the request. |

async ping(  url: string,  timeout: number,): void

Check that a connection to the ElasticSearch server can be established. Will throw an error after timeout.

• url* string: The ElasticSearch URL.
• timeout* number: The timeout for the request in ms.

CLI

Logarithm also provides a CLI tool to be able to install index patterns and a pipeline for the use by the middleware API.

logarithm -h

ElasticSearch utility for creating a pipeline and index templates
for logging request using logarithm middleware.

  logarithm <url> [-TPS] [-p pipeline] [-d]

	url            	The ElasticSearch URL.
	               	If protocol is not given, `http` is assumed.
	--stats, -s    	Display statistics by indices.
	--templates, -T	List all index templates.
	--delete, -d   	Delete an index, snapshot or pipeline.
	               	Used with the relevant flag.
	--index, -i    	Select an index for operations.
	--pipeline, -p 	Create a pipeline with `User-Agent`
	               	and `GeoIp` plugins.
	--pipelines, -P	Display installed pipelines.
	--snapshots, -S	List registered snapshot repositories.
	--help, -h     	Print the help information and exit.
	--version, -v  	Show the version's number and exit.

Snapshots: used to print info, create and restore snapshots.

  logarithm <url> [-r repo] [-s snapshot] [-s3 snapshot --bucket bucket] [--status|-d]

	--repository-s3, -s3	Create a new `s3` snapshot repo with this name.
	--bucket            	The bucket name for the `s3` snapshot repository.
	--repo, -r          	The name of the repo.
	--snapshot, -s      	The name of the snapshot.
	--restore           	Restore this snapshot.
	--status            	Fetch the status.

Templates: creates a template for an app.

  logarithm <url> -t {app-name} [-s shards] [-r replicas] [-d]

	--template, -t	Create an index template for storing
	              	log data in the `{template}-*` index.
	--shards, -s  	The number of shards for index template.
	              	Default: 1.
	--replicas, -r	The number of replicas for index template.

Methods: send data from JSON files.

  logarithm <url> [--post data.json] -p path

	--post    	Send POST request with data from the file.
	--path, -p	The path to send a request to.

📙 Read Wiki For More Documentation

List Templates, -T

To see what templates are installed.

logarithm 192.168.0.1:9200 -T

Name                           Patterns          Shards  Replicas
kibana_index_template:.kibana  .kibana           1
hits-logarithm.page            logarithm.page-*  1       0
hits-clients                   clients-*         1       0
hits-client2                   client2-*         1       0

Statistics, -s

The stats can be used to monitor created indices.

logarithm 192.168.0.1:9200 -s

Name                      Memory    Docs  Size
logarithm.page          11.6 KB   1     21.6 KB
logarithm.page-2018.12  60.4 KB   8859  3.3 MB
logarithm.page-2018.11  64.4 KB   116   179.5 KB
logarithm.page-2019.2   151.4 KB  63    279.1 KB
logarithm.page-2019.1   120.7 KB  5747  2.2 MB

Copyright & License

GNU Affero General Public License v3.0