expressjs-plus

ExpressPlus

Kind: global class

• ExpressPlus
  • new exports.ExpressPlus(app, passedParamHandlers, passedErrorHandlers)
  • instance
    • .HTTPError
      • new this.HTTPError(status, errCode)
    • .getMiddlewareVersion ⇒
    • .setErrorHandlers()
    • .responder(req, res, next)
    • .defaultCbWithResponse(cb, [status])
    • .defaultCb(cb, [resource])
    • .useArray(middlewares)
  • inner
    • ~lastHandler(param, paramsArray, req) ⇒ boolean

new ExpressPlus(app, passedParamHandlers, passedErrorHandlers)

Param	Type	Description
app	Object	express app object
passedParamHandlers	Array	array of functions in the format of @see lastHandler
passedErrorHandlers	Array	array of middlewares

Example
// Usage

var express = require('express');
var bodyParser = require('body-parser');
var userHandler = function(param, paramsArray, req){
    if(param !== 'user') return false;
    paramsArray.push(req.user);
    return true;
};
var app = express()
app.use(bodyParser.json());
var appPlus = new ExpressPlus(app, [userHandler], []);
var regularFunction = function(user, id, cb){
    return cb(null, { response: {user: user, id: id}, status: 200 });
};
app.use(appPlus.GMV(regularFunction), appPlus.responder);

appPlus.setErrorHandlers();

Example
//this is an example of a paramHandler function that is interested in the user parameter

function userHandler(param, paramsArray, req){
    if(param === 'user'){
        paramsArray.push(req.user);
        return true;
    }else{
        return false;
    }
}

expressPlus.HTTPError

Kind: instance class of ExpressPlus

new this.HTTPError(status, errCode)

Generic error handler

Param	Type	Description
status	Number	HTTP error code
errCode	String	errorCode, the error handler should handle this

expressPlus.getMiddlewareVersion ⇒

Returns a middleware version of the function passed, this function replaces the last parameter with a callback function to work with express js.

Kind: instance property of ExpressPlus
Returns: function

Param	Type	Description
func	function	the function to be converted

Example

function regularFunc(someVar, cb){
    console.log(someVar);
    return cb(null, {response: someVar+="addedString"});
}
// middleware version of regularFunc
var func = GMV(regularFunc);

// func will behave like this
function mw(req, res, next){
    let someVar = req.query.someVar;
    console.log(someVar);
    res.locals.response = someVar+="addedString";
    return next();
}

expressPlus.setErrorHandlers()

sets error handlers, make sure to use this last

Kind: instance method of ExpressPlus

expressPlus.responder(req, res, next)

Handles responses. Other middlewares need to use locals to pass data to this function

Kind: instance method of ExpressPlus

Param	Type	Description
req	Object	request object
res	Object	response object
res.status	function	function to set the status
res.locals	Object	object that is used to pass data around
res.locals.status	Number	Contains HTTP status code
res.locals.response	Object	Contains the response body
next	function

expressPlus.defaultCbWithResponse(cb, [status])

Handles callbacks and puts response & status in the second callback argument if successful Replace your callback with this if appropriate.

Kind: instance method of ExpressPlus

Param	Type	Default	Description
cb	function		callback function
[status]	Number	204	optional argument to pass specific HTTP code if no errors were found if the status is 204, no response will be returns according to HTTP codes.

expressPlus.defaultCb(cb, [resource])

Handles callbacks. Replace your callback with this if appropriate.

Kind: instance method of ExpressPlus

Param	Type	Description
cb	function	callback function
[resource]	Object	optional argument to return instead of the actual result

expressPlus.useArray(middlewares)

Enables sending array of middlewares to app.use

Kind: instance method of ExpressPlus

Param
middlewares

ExpressPlus~lastHandler(param, paramsArray, req) ⇒ boolean

Default parameter handler used in getMiddlewareVersion. Every parameter is passed to a set of functions to be handled, this is the last handler that just pushes the parameter to the paramsArray.

Kind: inner method of ExpressPlus
Returns: boolean - if true is returned, the parameter will be considered handled and the function GMV will move on to the next parameter. if false is returned, the next handler on the list will attempt to handle the parameter until this methods turn comes, which will always return true
See: dataHandler this function is a more real example of a parameter handler, it is used to integrate with another library https://www.npmjs.com/package/simple-express-validator

Param	Type	Description
param	String	string parameter
paramsArray	Array	parameter arrays which will be sent to the underlying function of the middleware
req	Object	express request object that is used in middlewares