Knetik Micro Core

This package defines an application structure for deploying a traditional node project with a multi tenant workflow.

Micro Core is built on a multi tenant premise. On project Init the Core app is setup with all the required dependencies and adaptors but no connections are made. When a customer connects, a connection is made, an instance of Core is created scoped to that user's environment and returned as App. Use App to access user scoped data and clients. Use Core to access all non multi tenant functionality.

Setup

1. Setup an npm project as usual.

mkdir myAppName
cd myAppName
npm/yarn init

2. Add the micro-core package

npm i --save @knetik/micro-core
# or
yarn add @knetik/micro-core

3. Add adaptors - https://www.npmjs.com/search?q=%40knetik/micro

npm i --save @knetik/micro-mongoose @knetik/micro-knetikcloud
# or
yarn add @knetik/micro-mongoose @knetik/micro-knetikcloud

4. Genrate the App skeleton

node ./node_modules/.bin/micro-new
(Windows powershell) yarn run micro-new

Development

There are README files throughout the application. A bit of explanation and an example go a long way.

enter the REPL

micro-core provides a REPL to assist in the development process. Enter the REPL with:

node ./node_modules/.bin/micro-console

Once the REPL returns a promt:

• Enter Core and hit return. Yeah, that's where the magic happens.
• Try Core.connect(<an_app_id>, [oauth_token]).then(App => console.log(App))

The REPL gives you full access to your entrie application right in your terminal. more on REPLs

to boot the http server

node ./node_modules/.bin/micro-serve

The app_id is resolved from the first subdomian segment of requesting domain or from the configured APP_ID_KEY request header. Which defaults to x-knetikcloud-appid

Testing

Still working on a way to include jasmine as a dev dependency from the package. For now just install the required packages.

npm i --save-dev @knetik/micro-test
# or
yarn add --dev @knetik/micro-test

• run node ./node_modules/.bin/micro-test or jasmine from the project root, specs go in the spec directory. :)

Deploy

Use serverless to deploy to lambda.

• install the serverless cli - npm install -g serverless
• Update the sls.yml files in .dist with the correct info
• copy the correct sls.yml file to the project root - cp ./dist/sls.development.yml ./serverless.yml
• run sls deploy to deploy
• running sls info returns the API Gateway url. Visit your newly deployed application in the browser.

App Functionality

Configs

Configs are stored in config/environments/{env}.json. On App init variables are merged into process.env.

Logger

There are 2 primary loggers in a micro-core application. The Core.Logger and the App.Logger. App.Logger is scoped to the client and attached to the client's app instance on Core.connect.

Load Paths

Any directory added inside app is auto loaded. Modules inside the app sub directories require an exported function with a single App parameter. The return value of the function will is made available with the get() method. App.get('{directory_name}.{module_name}')

get() accepts snake_case or PascalCase dot separated paths.

'services.example_service' or 'Services.ExampleService'

• module example
• usage example

Initializers

Initializers are stored in config/initializers and are loaded after Core.init and before Core.serve. Now is the time to setup custom libraries and other project specific configurations. Tools that are not Multi Tenant should be setup here. Maybe AWS libs or a Google SDK. Attaching initialized services to Core is encouraged.

Credentials Store

On init a CredentialsStore object is assigned to the Core application. This is a simple key value store exposing three methods.

Core.CredentialsStore.set(key, value) // => promise(value)
Core.CredentialsStore.get(key) // => promise(value)
Core.CredentialsStore.remove(key) // => promise(boolean)

The default is an in memory store. But configuration is made available for using other providers. EXAMPLE

On App.connect a credential store is assigned to the returned app instance and is scoped to the app_id

Core.connect(app_id)
.then(App => {
  App.CredentialsStore.set(key, value) // => promise(value)
  App.CredentialsStore.get(key) // => promise(value)
  App.CredentialsStore.remove(key) // => promise(boolean)
})

Core Adaptors

A core adaptor is defined by any lib that hooks into the Core init process. Core Adaptors are npm packages that export an Adaptor class exposing a single static function

• init: Setup any library prerequisites that are the same on any client.

Include a core adaptor in your micro-core app by:

• Adding the adaptor package to your project
  • Available adaptors: https://www.npmjs.com/search?q=%40knetik%2Fmicro
• Then add it to the config .json file in the CORE_ADAPTORS array.

Adaptors

An adaptor is defined by any lib that hooks into the Core init process. Some may support multi tenancy I.E. Postgres, Mongoose, Redis, Knetikcloud. Adaptors are npm packages that export an Adaptor class exposing 4 static functions

• init: Setup any library prerequsites that are the same on any client. Multi tenant Adaptors must make a call to App.AdaptorInitializer.add(adaptor_name, this /* adaptor class */)
• configDefaults: defines the required config variables that are imported when micro-new is run.
• connect: Required for multi tenant adaptors only. Should receive an App instance as a parameter, create a connection to the wrapped library scoped to the app instance, return the connection or an instance of the adaptor holding the connection.
• addInitializers: Is run during Core.init after initializer load and before express listen. It accepts a single Core parameter and no return value is expected. Do anything you want with Core at this point.

Include an adaptor in your micro-core app by:

• Adding the adaptor package to your project
  • Available adaptors: https://www.npmjs.com/search?q=%40knetik%2Fmicro
• Then add it to the config .json file in the adaptors array.
• TODO: Adaptor configs are not merged after micro-new has been run