backend-js

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

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📦 Installation

npm install backend-js

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🚀 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).

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🧩 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.

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🔍 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.

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🧱 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

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⚙️ 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.

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🧬 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());

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🚀 Starter Project

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

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

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📄 License

• MIT.