basic-subleveler

basic-subleveler

2.x versions have only been tested on Node 12 and 10. 1.x versions worked on Node 8, but do not work on Node 10 and up.

Handles boilerplate setup for one-level-deep LevelDB sublevel databases:

• Creates levels using the names and namespaces you provide.
• Gives you access to the close method on the db, so you can avoid unnecessary locking.
• Provides a "readAllValuesFromSublevel" method.

Installation

npm install basic-subleveler

Usage

var basicSubleveler = require('basic-subleveler');
var level = require('level');
var queue = require('queue-async');

var leveldb = level(
  __dirname + '/test.db',
  {
    valueEncoding: 'json'
  }
);

var db = basicSubleveler.setUpSubleveledDB({
  db: leveldb,
  sublevels: {
    meats: 'm',
    vegetables: 'v'
  }
});

// Will decorate the LevelDB instance with `meats` and `vegetables`
// sublevels. You can do stuff with them.

var q = queue();

q.defer(db.vegetables.put, 'broccoli', 'tasty');
q.defer(db.vegetables.put, 'tomato', 'juicy');
q.defer(db.vegetables.put, 'arugula', 'elitist');

q.awaitAll(readVegetables);

function readVegetables(error) {
  if (error) {
    console.log(error);
  }
  else {
    db.vegetables.readAllValues(logVegetables);
  }
}

function logVegetables(error, vegetables) {
  if (error) {
    console.log(error);
  }
  else {
    console.log(vegetables);
  }
}

Output:

[ 'tasty', 'juicy', 'elitist' ]

Tests

Run tests with make test.

License

The MIT License (MIT)

Copyright (c) 2015 Jim Kang

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.