backend-js

Backend-js is a layer built above expressjs and socket.io to enable the Behaviours Framework for Node.js applications.

📦 Installation

npm install backend-js

🚀 Usage

🔧 Backend Initialization

var backend = require('backend-js');
var App = backend.app(__dirname + '/behaviours', {
    path: '/api/v1',
    parser: 'json',
    port: 8383,
    origins: '*'
});

var App = app(path, options)

| Parameter | Type | Description | |-----------------------|---------|--------------------------------------------------------------------------------------------------| | path | string | Path to the behaviours directory. | | options | object | App configuration options. | | options.path | string | Prefix path appended to the beginning of routes. | | options.parser | string | Supports json, text, raw, or urlencoded. Parses request/response body accordingly. | | options.parserOptions | object | Options for body-parser. | | options.port | number | Port of the server. | | options.origins | string | Allowed AJAX origins (comma-separated or "*" for all). | | options.static | object | Options for serving static files. | | options.static.route| string | Virtual route for static content. | | options.static.path | string | Path to directory containing static files. |

| Returns | Type | Description | |---------|----------|--------------------------------------------------------------------------------------| | App | function | Express app instance (API reference). |

🧩 Model Definition

var backend = require('backend-js');
var model = backend.model();
var User = model({
  name: 'User'
}, {
  username: String,
  password: String
});

var ModelEntity = model(options, attributes, plugins)

| Parameter | Type | Description | |-------------------|--------------------|------------------------------------------------------------------------------------------------------------------| | options | string | object | Model name or full configuration object. | | options.name | string | Name of the model. | | options.features| object | Custom model features passed to the data access layer. | | options.query | array | Default query represented by QueryExpression. | | attributes | object | Schema attributes (String, Number, Date). Supports nested objects or arrays. | | plugins | array | Array of mongoose plugins. |

| Returns | Type | Description | |--------------|----------|------------------------------------------| | ModelEntity| function | Constructor for the defined model entity. |

🔍 Query Builder

var QueryExpression = backend.QueryExpression;
var ComparisonOperators = {
    EQUAL: '=',
    NE: '$ne'
};
var LogicalOperators = {
    AND: '$and',
    OR: '$or',
    NOT: '$not'
};
backend.setComparisonOperators(ComparisonOperators);
backend.setLogicalOperators(LogicalOperators);

var query = [
  new QueryExpression({
    fieldName: 'username',
    comparisonOperator: ComparisonOperators.EQUAL,
    fieldValue: 'name'
  }),
  new QueryExpression({
    fieldName: 'password',
    comparisonOperator: ComparisonOperators.EQUAL,
    fieldValue: 'pass',
    logicalOperator: LogicalOperators.AND,
    contextualLevel: 0
  })
];

setComparisonOperators(operators) / setLogicalOperators(operators)

| Parameter | Type | Description | |-----------|--------|-----------------------------------------------------------------------------| | operators | object | Key-value pairs mapping to database engine operators (used by data access). |

var expression = new QueryExpression(options)

| Parameter | Type | Description | |-----------------------|--------|-------------------------------------------------------------------------------------------------| | options.fieldName | string | Field name in the model. | | options.comparisonOperator | string | Comparison operator (=, $ne, etc.). | | options.fieldValue | any | Value to compare against the field. | | options.logicalOperator | string | Logical operator ($and, $or, $not). | | options.contextualLevel | number | Nesting level of conditions (for grouping). |

| Returns | Type | Description | |-------------|--------|-----------------------------------------------------------------------------| | expression| object | Query expression object used in queries. |

🧱 Entity API

var ModelEntity = backend.ModelEntity;
var entity = new ModelEntity({});
var model = entity.getObjectConstructor();
var schema = entity.getObjectAttributes();
var features = entity.getObjectFeatures();
var query = entity.getObjectQuery();

var entity = new ModelEntity(features)

| Parameter | Type | Description | |---------------|--------|------------------------------------------------------------------------------| | features | object | Special model functionalities passed to the data access layer.|

| Returns | Type | Description | |--------------|--------|------------------------------------| | entity | object | Holds model metadata and schema. |

Entity Methods:

• getObjectConstructor() – returns model constructor
• getObjectAttributes() – returns schema fields
• getObjectFeatures() – returns model features
• getObjectQuery() – returns default query array

⚙️ Behaviour (API Unit)

var getUsers = behaviour({
  name: 'GetUsers',
  version: '1',
  path: '/users',
  method: 'GET'
}, function(init) {
  return function() {
    var self = init.apply(this, arguments).self();
    self.begin('Query', function(key, businessController, operation) {
        operation
          .entity(new User())
          .append(true)
          .apply();
    });
  };
});

var Behavior = behaviour(option, constructor)

| Parameter | Type | Description | |---------------|----------|-----------------------------------------------------------------------------| | option | object | API metadata (name, version, path, method, params, returns). | | constructor | function | Business logic with database or response mapping functionality. |

🧬 Data Access

Define your own data access layer like below:

var backend = require('backend-js');

var ModelController = function () {
    self.removeObjects = function (queryExprs, entity, callback) {
        // do remove
    };
    self.addObjects = function (objsAttributes, entity, callback) {
        // do add new
    };
    self.getObjects = function (queryExprs, entity, callback) {
        // do select
    };
    self.save = function (callback, oldSession) {
        // do save
    };
};

ModelController.defineEntity = function (name, attributes) {
    // define entity
    return entity;
};

ModelController.prototype.constructor = ModelController;

backend.setModelController(new ModelController());

🚀 Starter Project

Explore the official starter to learn Backend-JS with examples:

🔗 https://github.com/QuaNode/BeamJS-Start

📄 License

• MIT.