logsmithjs v0.0.4

LogsmithJS

LogsmithJS is a Logging Library for Node JS apps with support for logsmith-monitor.

Getting Started

Install LogsmithJS using npm

npm i logsmithjs

Import the Logsmith object to use LogsmithJS.

import Logsmith  from "logsmithjs"

const log = new Logsmith({})

log.INFO("this is working fine")

While a logsmithJS supports a no-config setup, there are some configurations that can be tweaked as per need. Read More

For Logsmith-Monitor Support, go here.

Usage

Logsmith JS provides several Log Level based logging methods. It also provides a customizable logging method that can be used to log with a custom log level other than the ones provided. The methods can take both JSON and Statements as valid log.

log.SUCCESS()

log.SUCCESS() can be used to log Successful events and actions. Example:

log.SUCCESS({"test" : "passed"})
log.SUCCESS("The Tests Passed!")

log.INFO()

log.INFO() can be used to log Informational messages/prompts. Example:

log.INFO({"status" : "ok"})
log.INFO("The System is OK")

log.WARN()

log.WARN() can be used to log Warnings. Example:

log.WARN({"status" : "The system may be Vulnerable"})
log.WARN("The system may be Vulnerable")

log.FAILURE()

log.FAILURE() can be used to log Failures. Example:

log.FAILURE({"test" : "failed"})
log.FAILURE("The Tests Failed.")

log.CRITICAL()

log.CRITICAL() can be used to log events that may lead to system shutdowns, data loss or other critically fatal events. Example:

log.CRITICAL({"system" : "meltdown"})
log.CRITICAL("The system is Shutting Down.")

log.LOG()

This method provides the custom log level logging capability. This method takes a parameter loglevel other than the log itself. The loglevel can be set to any string. Example:

log.LOG(loglevel="TEST", {"test": "passed"})
log.LOG(loglevel="TEST", "The test Passed")

Configurations

To use logsmith, certain configurations are required. If no configs are provided then the default values are set. A basic logsmith config looks something like this.

{
    "env": "test",
    "logfile": "path/to/local/log/file",
    "consoleOnly": false,
    "logStatementPattern": "[ {component} ~ {logLevel} ] : {message}",
    "logFormat": "json",
    "monitorLogging": true
}

The Various flags/fields that can be configured are

Using Configurations

Configurations can be defined and used in an application by creating the config json and passing it to the Logsmith object while initializing.

import Logsmith  from "logsmithjs"

const logConfig = {
    "env": "test",
    "logfile": "path/to/local/log/file",
    "consoleOnly": false,
    "logStatementPattern": "[ {component} ~ {logLevel} ] : {message}",
    "logFormat": "json",
    "monitorLogging": true
}

const log = new Logsmith(logConfig)

Configurations may also be loaded from JSON files. Define the Configurations in a JSON file and load it using fetchConfigFromFile() method.

import Logsmith from "logsmithjs"

const log = new Logsmith({});

log.fetchConfigFromFile("/path/to/config/file.json")

Support for Logsmith Monitor

Logsmith Monitor (or simply Monitor) is a stand-alone logging Server for multi-component apps. Read about logsmith-monitor here.

LogsmithJS supports logging to Monitor. It pro creation of Publishers and Context

Monitor Configurations

There are some specific connfigurations that are required to log to logsmith monitor. A basic and minimum configuration has the following fields, along with the configurations mentioned above.

The Configurations for monitor support are defined as a JSON Object with "monitor" as the key.

{
    "monitor": {
        "port": "8080",
        "server": "localhost",
        "publisher": {
            "publisher": "testapp001"
        },
        "context": {
            "context": "testcontext001"
        }
    }
}

The fields required for monitor support are

The publisher and context fields are used to define their respective configs. The bare minimum publisher and context information that must be provided are the namespaces.

For Publisher Configurations, the field that needs to be put is the publisher name. Eg:

"publisher": {
    "publisher": "<publsiher-name>"
}

For Context Configurations, the field that needs to be put is the context name. Eg:

"context": {
    "context": "<context-name>"
}

There are other customizable fields for either. These fields are same as that defined for running Monitor.

• Read More about the configurations for Publisher
• Read More about the configurations for Contexts

When these values are not mentioned/provided by the user, logsmith creates/generates those for you. So the Configuration Above becomes

"monitorConfigs": {
    "monitorPort": "8080",
    "monitorURI": "localhost",
    "monitorProtocol": "http",
    "monitorListener": "http://localhost:8080",
    "publisher": {
        "publisher": "testapp001",
        "origin": "app.testapp001.com",
        "description": "Logs Published by testapp001"
    },
    "context": {
        "context": "testcontext001",
        "origin": "app.testapp001.com/testcontext001",
        "description": "Logs Published by testapp001",
        "kind": []
    }
}

Initializing Monitor Connection

Logsmith provides a method - initializeMonitor(), to initialize a connection with the monitor. The method checks if the Publisher and Context Namespaces are available in monitor and creates them if not.

const log = new Logsmith({})
log.fetchConfigFromFile("/path/to/file.json")

// initialize Monitor
log.initializeMonitor()

Know More

Some general information about some of the components in logsmithjs.

Log Statement Patterns

Log Statement Patterns are strings with placeholder that are used to print logs on-to the local console in the same format. The placeholders are identified by the names of the fields (in log) and placeholders names are defined in the string by enclosing them within curly-braces {}.

Example Usage

import Logsmith  from "logsmithjs";

const logStatementPattern = "{timestamp} > {status}"
const log = new Logsmith({logStatementPattern : logStatementPattern})

log.INFO({"timetamp": "11 AM", "status" : "ok", "action": "create"})

The above code logs a custom log statement

11 AM > ok

Example Application

To test Logsmith and Logsmith-Monitor in Action, we created this example application.

Startup Logsmith Monitor in Docker

docker pull ghcr.io/tanmoysg/logsmith-monitor:v0.0.5

docker run ghcr.io/tanmoysg/logsmith-monitor:v0.0.5

Go to the examples directory. Start the example Express App.

node .

Once the Server starts, it gives an endpoint for each logging method. The Endpoints available are

• {express-app-url}/warn
• {express-app-url}/info
• {express-app-url}/critical
• {express-app-url}/success
• {express-app-url}/failure
• {express-app-url}/log

These can be tested using cURL

curl localhost:8096/info

The logs should be printed both on the monitor as well as the example app terminal. Play around with the config for more customization.

Known Issues

There are some issues that we are working on to solve. List of the known issues and their temporary remediation are available here.