Internationalization (i18n) of REST APIs and REST service

[plavjanik]

As a developer of the REST API, I would like to know how to do the i18n easily and consistently with other Broadcom products.

• A way how to define i18n for strings in the code
• A way how to define i18n for numbered messages (ErrorService)
• A method of how the required locale is provided to the REST API is defined and propagated the code that is getting the strings or messages, ideally with a little coding
• A method how the service default locale is defined/configured and used in the threads that are not connected to a REST API request
• Greeting endpoint is localized
• Server messages are localized
• Czech or other localization is provided (for testing purposes)
• Swagger documentation - defined as a new story - Support internationalization of Swagger documentation #73

[plavjanik]

Hello, @dkelosky. I have created this story for i18n. It seems that facilities for it in Spring Boot are quite powerful and this story will be more about using them properly and explaining it to the users of the SDK and sample and connecting it to the ErrorService.

[plavjanik]

https://www.baeldung.com/spring-boot-internationalization
https://www.mkammerer.de/blog/spring-boot-locale-resolver/
https://dzone.com/articles/learn-how-to-internationalize-and-localize-your-ja
http://springfox.github.io/springfox/docs/current/#property-file-lookup or springfox/springfox#1180

Inspiration: https://angular.io/cli/xi18n

[plavjanik]

Everything but #73 was implemented in #68.