62 lines
1.6 KiB
Org Mode
62 lines
1.6 KiB
Org Mode
#+TITLE: Service Oriented Programming
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#+Author: Yann Esposito
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#+Date: [2021-06-06]
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- tags :: [[file:2020-06-03--19-49-30Z--programming.org][programming]] [[file:2021-03-20--17-27-46Z--architecture.org][architecture]]
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- source ::
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This is a presentation of a design pattern to architecture a big code
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source.
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As most programming architecture, the goal is to optimize modularity.
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First, this focus on functions.
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There will be no global variable.
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There are two kind of functions in programming, pure and impure functions.
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From a high level perspective:
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- =lib/= contain pure functions
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- =services/= contain all services
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The services directory will contain "sub-project"/"modules".
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Every service should have the following structure:
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- =src/=
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+ =service= the service declaration
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+ =core= the implementation of the function in the service, should
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contain pure functions
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+ =schemas/types= the metas structures (data format mostly)
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+ =routes= if you service is a web service, routes declarations
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- =test/=
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+ =service_test= the service test
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+ =core_test= the tests for pure functions
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A service should be considered as a function returning a record of functions.
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#+begin_src
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foo-service-methods
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foo-do-a
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foo-do-b
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foo-do-c
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def foo-service
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create-service( config-service, bar-service, baz-service)
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#+end_src
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The component will form an acyclic graph of dependencies.
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Principles:
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A service contain an internal state.
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Every method of the service can access this internal state.
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No OOP is needed, only functions.
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Ability to test isolated.
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You can write:
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#+begin_src
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with-services-and-conf services conf
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test-the-services
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#+end_src
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