keydb

keydb

Build data APIs using the middleware concept.

Installation

npm

npm install keydb

Usage

By default, KeyDB is a middleware stack that does nothing. At a minimum, you must provide it with a data source. A data source is just a function that returns data.

var keydb = require('keydb');

var db = keydb();

db.source(function (msg) {
  return msg;
});

db("Hello, World!").then(function (msg) {
  console.log(msg);
});

The above database will simply echo the message sent to it. That's not very useful. To do something more useful, use the included drivers.

var keydb = require('keydb');

var db = keydb();

db.driver(keydb.drivers.upsert);
db.driver(keydb.drivers.mysql, {
  database: 'test',
    tables: {
      user: {
        properties: {
          user_id: {
            type: 'string',
            maxLength: 100
          },
          first_name: {
            type: 'string',
            maxLength: 100
          },
          last_name: {
            type: 'string',
            maxLength: 100
          }
        },
        primaryKey: 'user_id'
      }
    }
});

db({
    op: 'upsert',
    attributes: {
      user_id: 'joe', first_name: 'Joe', last_name: 'Foo'
    },
    filters: {user_id: 'joe'}
  })
  .then(function () {
    return db({op: 'query', filters: {user_id: 'joe'}});
  })
  .then(function (msg) {
    console.log(msg.items);
  })

In the above example, an upsert driver is stacked on top of a mysql driver so that upsert semantics can be added to mysql without the underlying driver actually supporting upsert.

Some drivers are preconfigured stacks, and these can be easily created by their IDs. They may also add sugar methods.

var keydb = require('keydb');

var db = keydb('kv-mysql');

db.set('users/joe', {firstName: 'Joe'})
  .then(function () {
    return db.get('users/joe');
  })

The above is the same as:

var keydb = require('keydb');

var db = keydb('kv-mysql');

db({op: 'set', key: 'users/joe', value: {firstName: 'Joe'}})
  .then(function () {
    return db({op: 'get', key: 'users/joe'});
  })