V2.3.x into master

[MatteoDiPaolo]

Description

This PR will add to the generator-systemic the possibility to generate not only the basic and without-business-logic version of a systemic-based microservice but as well the show-case version of it.

Once again with this approach we

• do not pollute the systemic-generator code and have to maintain 2 version of it
  • yo systemic
  • yo systemic:advanced
• do not have to bother the user with the useless and always NO answered question Would you like to have a showcase including extra components?

Usage:

• basic version: yo systemic
  • highlights the un-opinionated approach of systemic about how to create microservices. We give the users a base and they define which type of business logic they want to implement (rest + DB / bus + DB / bus + blob / rest + third party integration / etc.)
• show-case version: yo systemic --extra-components
  • lets the user understand how to get the most out of a systemic-based microservice.
  • fosters the implementation of an Hexagon Architecture for the microservice.
  • gives an hint of how to manage multiple business logic workflows in the same microservice.
  • gives an hint of how to manage versioning of components.
  • gives an hint of how to manage integration testing.
  • gives an hint of how to manage the infrastructure for a given microservice with docker-compose.
  • gives an hint of how big the systemic ecosystem is when it comes to already available npm systemic components (systemic-rabbitmq, systemic-mongodb).

How to review this PR

The newly added --extra-components flag is retrieved in generators/app/index.js and then set as a prop for the generator. That prop is the one used in order to:

• add or not add a given file to the generated microservice.
  • Check props.filesToSkip in generators/app/index.js
• add or not add a given bit of code to a file ending up being part of the generated microservice
  • e.g. <%_ if (extraComponents) { -%> "error-handler-module": "^1.0.3", <%_ } -%> in generators/app/root/_package.json

A more detailed description of this new capabilities can be found in:

• README.md
• generators/app/templates/root/_README.md

I would recommend to the reviewers to run yo systemic --extra-components and check the generated microservice starting from a carefully reading fo the generated README.

Issues solved by this PR

• 17 --> the error-handler-module package has been added in the show-case version in order to show http errors handling capabilities. This would made the PR #41 obsolete.

• 54

• 25

• 59

• 14

• 11

• 6

[UlisesGascon]

cc: @jgleal

[MatteoDiPaolo]

@kevinccbsg

It looks good to me. I would change this --extra-components to --showcase.

It makes sense I can go for it. --> done here

In the showcase @MatteoDiPaolo I would change the sleep command we use for the tests. I would add the infra and test scripts in the README so the developer will be aware that he needs the infra running to run the showcase tests. If I was using it I wouldn't like to wait for the sleep command on every test.

It makes sense I can go for it. --> done here

[MatteoDiPaolo]

@Betisman I see you reacting with emojis to messages in this PR, feel free to give us your point of view as well on this.

[Betisman]

@MatteoDiPaolo I would need a code review. 25 files about something I wasn't involved at all... please, help!

[feliun]

@MatteoDiPaolo I'm happy with this approach, I reviewed all files