bvwells/go-patterns

Design patterns for the Go programming language

Design Patterns for Go

Design patterns for the Go programming language.

import "github.com/bvwells/go-patterns"

To install the packages on your system,

$ go get -u github.com/bvwells/go-patterns/...

Documentation and examples are available at https://pkg.go.dev/github.com/bvwells/go-patterns?tab=overview

• Design Patterns
• Creational
• Structural
• Behavioral
• Go Versions Supported

Design Patterns

Pattern	Package	Description
Creational	creational	Creational design patterns are design patterns that deal with object creation mechanisms, trying to create objects in a manner suitable to the situation. The basic form of object creation could result in design problems or in added complexity to the design. Creational design patterns solve this problem by somehow controlling this object creation.
Structural	structural	Structural design patterns are design patterns that ease the design by identifying a simple way to realize relationships between entities.
Behavioral	behavioral	Behavioral design patterns are design patterns that identify common communication patterns between objects and realize these patterns. By doing so, these patterns increase flexibility in carrying out this communication.

Creational

Name	Description
Abstract Factory	Provide an interface for creating families of related or dependent objects without specifying their concrete classes.
Builder	Separate the construction of a complex object from its representation, allowing the same construction process to create various representations.
Factory Method	Define an interface for creating a single object, but let subclasses decide which class to instantiate. Factory Method lets a class defer instantiation to subclasses.
Object Pool	Avoid expensive acquisition and release of resources by recycling objects that are no longer in use. Can be considered a generalisation of connection pool and thread pool patterns.
Prototype	Specify the kinds of objects to create using a prototypical instance, and create new objects from the 'skeleton' of an existing object, thus boosting performance and keeping memory footprints to a minimum.
Singleton	Ensure a class has only one instance, and provide a global point of access to it.

Structural

Name	Description
Adapter	Convert the interface of a class into another interface clients expect. An adapter lets classes work together that could not otherwise because of incompatible interfaces. The enterprise integration pattern equivalent is the translator.
Bridge	Decouple an abstraction from its implementation allowing the two to vary independently.
Composite	Compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly.
Decorator	Attach additional responsibilities to an object dynamically keeping the same interface. Decorators provide a flexible alternative to subclassing for extending functionality.
Facade	Provide a unified interface to a set of interfaces in a subsystem. Facade defines a higher-level interface that makes the subsystem easier to use.
Flyweight	Use sharing to support large numbers of similar objects efficiently.
Proxy	Provide a surrogate or placeholder for another object to control access to it.

Behavioral

Name	Description
Chain of Responsibility	Avoid coupling the sender of a request to its receiver by giving more than one object a chance to handle the request. Chain the receiving objects and pass the request along the chain until an object handles it.
Command	Encapsulate a request as an object, thereby allowing for the parameterization of clients with different requests, and the queuing or logging of requests. It also allows for the support of undoable operations.
Interpreter	Given a language, define a representation for its grammar along with an interpreter that uses the representation to interpret sentences in the language.
Iterator	Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
Mediator	Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it allows their interaction to vary independently.
Memento	Without violating encapsulation, capture and externalize an object's internal state allowing the object to be restored to this state later.
Observer	Define a one-to-many dependency between objects where a state change in one object results in all its dependents being notified and updated automatically.
State	Allow an object to alter its behavior when its internal state changes. The object will appear to change its class.
Strategy	Define a family of algorithms, encapsulate each one, and make them interchangeable. Strategy lets the algorithm vary independently from clients that use it.
Template Method	Define the skeleton of an algorithm in an operation, deferring some steps to subclasses. Template method lets subclasses redefine certain steps of an algorithm without changing the algorithm's structure.
Visitor	Represent an operation to be performed on the elements of an object structure. Visitor lets a new operation be defined without changing the classes of the elements on which it operates.

Go Versions Supported

The most recent major version of Go is supported. You can see which versions are currently supported by looking at the lines following go: in .travis.yml.

go-patterns's Issues

Implement Visitor behavioral design pattern

Implement Visitor behavioral design pattern

Extension interface pattern

Russ Cox describes it in this video, I think it would be a great addition to the list.

question ?

nice resource :)
I am new to Golang.. but shouldn't Postman extend Worker in the Template Method pattern ?

Real world simple examples

Thanks for sharing this.

One suggestion: real world simple examples can help in better understanding of the patterns.

Some patterns are just telling what it does without bringing out the benefit of the pattern.

Using table driven test and go-capturer can help

I was practicing some patterns in my own repo and this repo has been really helpful in telling the basics in just few minutes. Thanks @bvwells

Just some suggestion to make it more easy to read:

1. Table driven tests at many places can simplify reading tests. Example.
2. Using go-capturer library (or keeping a copy of it in this repo) can also make testing easier to read and would reduce a lot of boilerplate code. Example.

Go - Concurrency Design Patterns

I think it'd be great if someone could add a concurrency design patterns section/part (goroutine & channels, select, fan-In & fan-out, mutex, etc.)!

Implement Interpreter behavioral design pattern

Implement Interpreter behavioral design pattern

Naming conventions are not idiomatic

Some naming conventions follow the java kind of naming convention like .
a.GetResult() instead of a.Result()

A good video on naming convention in go: https://www.youtube.com/watch?v=MzTcsI6tn-0&t=78s

"Write go like go team"

Implement Memento behavioral design pattern

Implement Memento behavioral design pattern

Implement Mediator behavioral design pattern

Implement Mediator behavioral design pattern

Implement Command behavioral design pattern

Implement Command behavioral design pattern

Implement Template Method behavioral design pattern

Implement Template Method behavioral design pattern

Implement State behavioral design pattern

Implement State behavioral design pattern

Implement Iterator behavioral design pattern

Implement Iterator behavioral design pattern