CerberusMVC

INTRODUCTION

Now Supports AWS (lambda), Azure (Func), ExpressJS (with child processes) and Socket.IO in Javascript and Typescript

CerberusMVC is simply a node MVC stack, that is used to create API's on FaaS backgrounds such as AWS's lambda, Google clouds compute, Azures function services as well as more natural Express JS setups and Socket.IO.

Why would it exist? If you have ever worked in serverless or have been involved with large FaaS architectures, you will soon find diversity brings issues. Diversity in developers, coding styles and rules leads to complicated, fragmented and overlapping capabilities, by virtue of the many individual functions generated by all those invloved. This means in simple terms, a mess. the mess is nto intentional, it just happens as naturally as entropy. We end up with many lambdas/computes/functions written all in slightly different ways, some with similar functionality and a loss of abstraction.

Other issues also exist, such as managing a collection of resources on a function based serverless architecture. You gain the strengths of the seperation and modularity but suffer in lost time, developement, repetion and the ability to orchastrate the collection as an entity in itself.

A FaaS serverless MVC stack offers a cure to both sides of this coin. We abstract the modularity with a known methodology, that of a singlular MVC stack that works in a regimented way. We also solve orchastration through tools to publish the stacks as their tue modular form through the many ways that the providers give us... an example of this would be SAM from AWS and cloudformation.

We simply build as a singluar MVC stack, test, develop, then publish to moduler resources, best of both worlds. Whilst for some providers, we may need to develop as a single function (azure) due to the innability to have a single routing file, all production pushes will generate individual functions and resources form the stack, wiht the MVC framework only pulling in what is needed for that particular route through the stack. AWS, openfass and forked processes all allow for development in as near to production as possible, with seperate endpoint functions, with azure having to develop in a single funciton and build to many on push. As the stack loads controllers on the fly, whilst we may push a full stack to each function, we will only laods the required items for that path through the system due to this on the fly loading. Future release may offer a more streamlined chunking of files to reduce files on each function, this will nto make any difference to memory when in use, just disk space.

CerberusMVC is a FaaS, serverless MVC architecture that is provider agnostic... currently supporting AWS configuration, Azure functions, Express JS forked server configuration and Socket.IO for basic VPS's, with the want to open this up to other platforms such as OpenFaaS, Azure. Our aim is to offer a way to build API's and deploy them easily, for many different providers as demand increases.

Want to know more, see more of CerberusMVC? We are all about MVP, we are happy to expand documentation, add in more support; let us know your thoughts... Find me here.

INSTALLATION

(recommended) Automatic installation, using the cerberus-cli (linux users might need sudo!). This will install the CLI tool and generate a base project at your current location (installaing cerberus-mvc during the process).

npm install -g cerberus-cli

cerberus-cli init

(not recommended) Manual installation, should you wish to create your won structure.

npm install cerberus-mvc

STRUCTURE

The basic structure is that of MVC, with controllers, models and obviously the views removed (however you could add these for serving things like email templates to email?). The specific structure is...

• Controller - the entry point in and the exit path out
• Library - any 3rd party bundled things, or maybe your own stuff
• Middleware - middlware that loads in order on in, out or both
• Model - connection to DB through models, connecting to knexjs
• Service - singleton services isntantiated at creation
• Template - location for text based templates

This structure is generated by the cerberus-cli tool when using the init command. in addition a handler template is generated, this is the bridge between your provider and CerberusMVC, the entry point into the stack. As stated above, controllers are lazy loaded, so we only load what we need for that path through the system, othe rcontroller dependencies will not be loaded unles that controller is lazy loaded when routing form your providers routing logic (e.g. AWS API gateway).

The controller start point is furnished with a request property that is passed into the controller. The request is a generic request that is generated form the providers event, that hits function/lambda/compute. the idea here is that we abstract the provider allowing us to write code that is portable to other providers! the exit path out the controller is a geenric response. Once hte repsonse has passed through middleware, the stack will auto convert it back to the required response for the provider. thi sallows us to generate API's we can port to other providers with minimal changes. The idea here is to offer multiplatform FaaS in MVC form to aid development and allow for simple porting.

All cerberus-mvc base classes expose 3 properties to help you in your apllication (inherited by Core)...

• this.$services - the services loaded into the system as an instantiated singleton
• this.$environment - any environment variables passed into the system (process.env)
• this.$client - any client specific information
• this.$socket - (socket.io only) any client specific information
• this.$io - (socket.io only) any client specific information

In addition to exposed properties, models also gain the raw db object... so it my talk directly to knexjs inside each model

• this.db

Documentation

Please visit CerberusMVC for details about the project and CerberusMVC for documentation.