SYNOPSIS

LevelDB Management. Includes simple data visualization tools.

MOTIVATION

• No need to configure Data Retention or storage-schemas.
• Nothing needs to be finite or determined ahead of time.
• No database initialization.
• Attach to an existing database or create one on the fly.
• Accept secure incoming data streams via tls.

USAGE

Run the server

Installation

npm install levelweb -g

Create an initial user account

levelweb -u admin -p password

Create keys and certs for the https and tls server. You can distribute the certificate to clients that wish to connect to the server.

# create a certificate and sign it.
openssl genrsa -out levelweb-key.pem 1024
openssl req -new -key levelweb-key.pem -out levelweb-csr.pem
openssl x509 -req -in levelweb-csr.pem -signkey levelweb-key.pem -out levelweb-cert.pem

Point the app at your database and specify what ports you want to run on and a host if it should be anything other than 127.0.0.1.

levelweb ./test/data --tls 9097 --https 8089 --host 165.125.122.142

Send data to the server

Level web accepts new line delimited writes over tls. Each line should be an object that contains a key and value, like so { key: 'foo', value: 'bar' }.

var tls = require('tls');
var path = require('path');
var fs = require('fs');

module.exports = function(server) {

  var origin;

  server.on('connection', function(data) {
    origin = data;
  });

  var authpath = path.join(process.cwd(), 'auth');

  var opts = {
    host: 'localhost',
    port: argv.port,

    key: fs.readFileSync(path.join(authpath, 'my-client-key.pem')),
    cert: fs.readFileSync(path.join(authpath, 'my-client-cert.pem')),
    ca: [fs.readFileSync(path.join(authpath, 'levelweb-cert.pem'))]
  };

  console.log('connecting to port %d', opts.port);

  var client = tls.connect(opts, function() {

    server.on('log', function(key, value) {

      var json = { key: key, value: value };

      client.write(JSON.stringify(json) + '\n');
    });
  });
};

Explore and manage keys and values

Visualizations

Treemap

Provides a zoomable tree-map of the currently tagged keys. Treemaps display hierarchical (tree-structured) data as a set of nested rectangles. Each branch of the tree is given a rectangle, which is then tiled with smaller rectangles representing sub-branches. A leaf node's rectangle has an area proportional to a specified dimension on the data. Often the leaf nodes are colored to show a separate dimension of the data.

When the color and size dimensions are correlated in some way with the tree structure, one can often easily see patterns that would be difficult to spot in other ways, such as if a certain color is particularly relevant. A second advantage of treemaps is that, by construction, they make efficient use of space. As a result, they can legibly display thousands of items on the screen simultaneously.

Stacked Bar Chart

Stacked Area Chart

Area charts are used to represent cumulated totals using numbers or percentages (stacked area charts in this case) over time. Use the area chart for showing trends over time among related attributes. The area chart is like the plot chart except that the area below the plotted line is filled in with color to indicate volume.

When multiple attributes are included, the first attribute is plotted as a line with color fill followed by the second attribute, and so on.