Updating Docs for Using / Writing Components

[virkt25]

Overview

Mixins can do something useful for components being used in a LBNext application. An example is the RepositoryMixin which takes any repositories declared by a component and binds the repositoryClass to repositories.*. The mixin also binds any repositories declared by the Application in the constructor as well as using the sugar method app.repository().

Writing Components Docs & Using Component Docs need to be updated to show users how they can interact with Mixins (Repository mixin above is just used as an example!).

Acceptance Criteria

• Update Docs
  • https://github.com/strongloop/loopback-next/wiki/Using-Components
  • https://github.com/strongloop/loopback-next/wiki/Writing-Components
  • possibly other places.

Note: Update on loopback.io instead

[jannyHou]

We probably should have a single page for concept mixin first
We probably should have a single page for language specific concepts first, and mixin is one of the JS concepts, we have lib function to build mixin to a baseClass.

here is some topic we can add in it:

• create a mixin function
• apply mixins by MixinBuilder from lib mixin.ts
• advanced topic: shall we support interface extends multiple classes as well?

Some refactor work:

• Move mixin.ts from repository to core
• Apply RepositoryMixin by MixinBuilder

[jannyHou]

Merged loopbackio/loopback.io#491 and close the issue.