attributes

Query a database (currently PostgreSQL or Sqlite3) for its schema — columns or attributes — and get their properties, such as name, type and default value in a common format. You can use this for e.g. introspection or preparing your domain models like Rails's Active Record does.

npm install attributes
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Attributes for Node.js

NPM version

Attributes allows you to easily query a database (currently PostgreSQL or Sqlite3) for its schema — columns or attributes — and get their properties such as name, type and default value, in a common format.

You can use this for introspection, to prepare your domain models and set up simple type coercions. This way you can have the same convenience that Ruby on Rails's ActiveRecord provides, but in the JavaScript world. Saves you from duplicating your model schema.

Attributes is most useful together with a model library that can make use of it automatically, but you can also just use with plain old JavaScript objects. I made this for the decoupled domain model library Soul.js that I'm writing.

Installing

Note: Must.js will follow the semantic versioning starting from v1.0.0.

npm install attributes

Using

Each database has its own function you can call passing it the connection to that database and the table name you'd like to get attributes for.

For example, with Sqlite3, just initialize the Database object and pass that to Attributes.sqlite3:

var Sqlite3 = require("sqlite3")
var db = new Sqlite3.Database("database.sqlite3")
var Attributes = require("attributes")
Attributes.sqlite3(db, "people", console.log)

For now, you'll have to know the table name in advance.

This works well if you have a single JavaScript "class" or model per database table. With Attributes you can initialize that model's attributes and their default values without having to manually keep the database and the model declaration in sync.

Full example

Given the following table:

CREATE TABLE "golfers" (
  "name" VARCHAR(255) DEFAULT 'Tiger' NOT NULL,
  "handicap" INTEGER DEFAULT 52 NOT NULL,
  "created_at" DATETIME
)

Calling Attributes:

var Pg = require("pg")
Pg.defaults.database = "golf"

var db = new Pg.Client
db.connect()

var Attributes = require("./")
Attributes.postgresql(db, "golfers", function(err, attributes) {})

Will call the callback with the following object for attributes:

{
  name: {null: false, type: String, default: "Tiger", limit: 255},
  handicap: {null: false, type: Number, default: 52, limit: null},
  updated_at: {null: true, type: Date, default: null, limit: null}
}

API

For extended documentation, please see the Attributes API Documentation.

Attributes

  • postgresql(connection, tableName, callback)
  • sqlite3(connection, tableName, callback)

Attribute

License

Attributes is released under a Lesser GNU Affero General Public License, which in summary means:

  • You can use this program for no cost.
  • You can use this program for both personal and commercial reasons.
  • You do not have to share your own program's code which uses this program.
  • You have to share modifications (e.g bug-fixes) you've made to this program.

For more convoluted language, see the LICENSE file.

About

Andri Möll typed this and the code.
Monday Calendar supported the engineering work.

If you find Attributes needs improving, please don't hesitate to type to me now at andri@dot.ee or create an issue online.

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