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Mossie Chao
Mossie Chao

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Go project structures

source & credit : thank you Kat Zień
video
repository

Goals

  • Consistent เพื่อให้โครงสร้างทุกส่วนของไปในทิศทางเดียวกัน
  • Easy to understand
  • Easy to change, loosely-coupled แก้ไขง่าย โดยไม่กระทบส่วนอื่น ๆ
  • East to test
  • Structure reflects the design exactly

Example

Beer reviewing service

Requirements

  1. Users can add a beer
  2. Users can add a review for a beer
  3. Users can list all beers
  4. Users can list all reviews for a selected beer.
  5. Option to store data either in memory or JSON file
  6. Ability to add some sample data

Flat structure

📦/
┣ 📜data.go
┣ 📜handlers.go
┣ 📜main.go
┣ 📜model.go
┣ 📜storage.go
┣ 📜storage_json.go
┣ 📜storage_mem.go
┗ 📜[file name]_test.go

main.go

  • Get storage [Requirement 5]
  • Call for routes to get service
  • Mock data [Requirement 6]
  • HTTP server listener

handlers.go

  • Manage with request (header, body, params,etc...)
  • Call data from storage

model.go

  • Entities struct

image


Group by function (Layered archetecture)

  • presentation / ui
  • business logic
  • external deps / infrastructure

📦/
┣ 📜data.go
┣ 📂handlers
┃ ┣ 📜beers.go
┃ ┗ 📜reviews.go
┣ 📂models
┃ ┣ 📜beer.go
┃ ┣ 📜review.go
┃ ┗ 📜storage.go
┗ 📂storage
┣ 📜json.go
┗ 📜memory.go

main.go

  • Call for routes to get service

handlers

  • request / response manage
  • get storage

storage

  • database services
    • struct
    • methods [ CRUD ]

Cons

เสี่ยงต่อการเกิด Circular dependencies สูง เช่น layer models ต้องถูกใช้งานจากทั้ง layer บน และ ล่าง


Group by module

📦/
┣ 📜main.go
┣ 📂beers
┃ ┣ 📜beer.go
┃ ┗ 📜handler.go
┣ 📂reviews
┃ ┣ 📜review.go
┃ ┣ 📜handler.go
┗ 📂storage
┣ 📜json.go
┣ 📜data.go
┣ 📜memory.go
┗ 📜storage.go

Cons

เสี่ยงต่อการเกิด Circular dependencies เนื่องจาก ข้อมูลมีการเชื่อมโยงกัน [Requirement 2, 4]

  • Beer ก็ใช้งาน Review
  • Review ก็ใช้งาน Beer

Group by context

Domain Driven Design

  • Estalish your domain and business logic
  • Define your bounded contexts, the models within each context and the ubiquitous language
  • Catagorising the building blocks of your system

Building blocks

  • Context beer tasting
  • Language beer, review, storage
  • Entities Beer, Review
  • Value Objects Brewery, Author
  • Aggregate Beer Reviewer
  • Service Beer adder / adding, Beer lister / listing, Review lister
  • Events Beer added, Review added, Beer already exists, Beer not found
  • Repository Beer repository, Review repository

📦/
┣ 📂adding
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂beers
┃ ┣ 📜beer.go
┃ ┗ 📜sample_beers.go
┣ 📂listing
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂reviewing
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂reviews
┃ ┣ 📜review.go
┃ ┗ 📜sample_reviews.go
┣ 📂storage
┃ ┣ 📜json.go
┃ ┣ 📜type.go
┃ ┗ 📜memory.go
┗ 📜main.go

mermaid-diagram-20210417094134


Hexagonal Architecture

📦/
┣ 📂cmd
┃ ┣ 📂beer-server
┃ ┃ ┗ 📜main.go
┃ ┗ 📂sample-data
┃ ┗ 📜main.go
┗ 📂pkg
┣ 📂adding
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂beers
┃ ┗ 📜beer.go
┣ 📂listing
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂reviewing
┃ ┣ 📜endpoint.go
┃ ┗ 📜service.go
┣ 📂reviews
┃ ┗ 📜review.go
┣ 📂storage
┃ ┣ 📜json.go
┃ ┣ 📜type.go
┃ ┗ 📜memory.go
┣ 📂http
┃ ┣ 📂rest
┃ ┃ ┗ 📜handler.go
┃ ┣ 📂soap
┃ ┗ 📂rpc
┣ 📂resources
┃ ┗ 📂sample-data
┃ ┣ 📜sample_beers.go
┃ ┗ 📜sample_reviews.go

cmd

  • commands to use service
    • use by request http protocal
    • use by using command line

resources/sample-data

  • seperate sample data to individual folder

Top comments (2)

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bias profile image
Tobias Nickel

hi, this is very cool, thanks, and also that the repo is there to see what is inside each file.

I see the repo is like 3 years old. do you think it would need some update? Does it reflect go-modules? and some internal directory?

I can not really judge that as I do not actively code using go for the last 2 years.

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mossnana profile image
Mossie Chao

Thank you :)

I think repository's owner may make requirements easy to understand and no encapsulation concept for internal directory.

P.S. I just started code with go for 6 months. I apologize if there are any mistakes.

:)