go-struct-builder

go-struct-builder

go-struct-builder is a tool that implements builder pattern for structs by using codegen

Installation

Go 1.18+

go install github.com/slavaavr/go-struct-builder/cmd/gosb@v1.0.0

Quick start

• To generate a struct builder add the appropriate go:generate comment:

// input.go - file where struct is located

//go:generate gosb -source=input.go
type A struct {
	F1 int
	F2 string
}

Then run the command:

go generate ./...

That's it. Examples can be found in the testdata folder.

Required / Optional fields

• There are two types of struct fields: required and optional. By default, every pointer** value is optional and the rest of them are required. To change the default behaviour add the appropriate struct tags:

//go:generate gosb -source=input.go
type B struct {
	F1 *int `gosb:"required"`
	F2 string `gosb:"optional"`
}

Generated builder will check if required fields were provided.

• For a private struct a private builder will be generated.
• If struct has private fields, along with the builder getter methods will be generated.

** and the Option type fromgithub.com/samber/mo package.

Flags

The gosb command is used to generate builder pattern for structs annotated with go:generate gosb comment. It supports the following flags:

• -source: A file containing struct the builder must be generated for
• -features: Comma separated list of features:
  • ptr: Generates additional method for every pointer field without the pointer in the argument
  • arr: Generates additional method for every array field by using vararg in the argument
  • opt: Generates additional method for every Option field provided by the github.com/samber/mo library by unwrapping the Option type and setting a value directly