Everlog

📔 High-performance fs logging with buffering, file retention, thread safety, CSV streams and log viewer for every day usage.

With CSV Streams (channels, tables) you make your logs structurable.

CLI

$ npm i -g everlog

# Help
$ everlog

# List all created channels
$ everlog list

# Get statistic for a channel: amount of lines, files, etc.
$ everlog stats foo

# Read N last lines from a channel. Supports params `offset` and `limit`
$ everlog read foo

# Start viewer web-app.
$ everlog server --port=5772

API ↗

1. Initialize the Everlog

import { Everlog } from 'everlog'

await Everlog.initialize({
    directory: `./logs/`,
    slack: {
        token: '',
        channelId: ''
    }
});

2. Create Log Streams

const channel = Everlog.createChannel('foo', {
    // Keep only last N files
    fileCountMax: 20,
    // Limit size for a file. When reached, next file is created
    fileBytesMax: 500 * 1024;
    // Limit message count for a file. When reached, next file is created
    fileMessagesMax: 10 ** 7

    // Buffer N messages
    messageBufferMax: 50;
    columns: [] as ICsvColumn[];

    // Flush logs, when no activity was for N milliseconds
    writeTimeout: null as number;

    columns: [
        { name: 'Title', filterable: true },
        { name: 'MyVal', type: 'number', sortable: true, groupable: true },
        { name: 'Timestamp', type: 'date', sortable: true, groupable: true },
    ]
});

channel.writeRow([`Lorem ipsum`, 123, new Date()]);

// On the application end flush the data (in case there is smth in the buffer)
Everlog.flush();

Dev

Core (/src/)

• Collects events from a server or from custom streams, and proceeds with persistence or further propagation (slack)
• Creates a subapp to view collected events

Viewer (/www/)

SubApplication to view/sort/filter collected events

• Development endpoints (unbuild source):
  • web: http://localhost:5771/index.dev.html
  • api, e.g: http://localhost:5771/api/logs/channels

Prepair

> npm i
> cd www/
> npm i

Start Example(Dev Project for the viewer)

# builds core to be available for example as lib
> npm run watch

# starts demo server with Core and Viewer attached
> npm run example

# navigate to http://localhost:5771/atma/monit/index.dev.html

🏁

©️ MIT License.