gog

README

gog

code generation for Go (WIP)

generates:

• Builder - gog:builder
• Getters - gog:getters
• AllArgsContructor - gog:allArgsContructor
• RequiredArgsContructor - gog:requiredArgsContructor
• Value Objects - gog:value
• Record - gog:record

Instalation

go install github.com/quintans/gog@latest

Quick Start

Comment your struct, with the generator tag // gog:record and then execute go generate ./....

Using go generate ./... will only process files annotated with //go:generate gog . Running gog -d <some dir>/... will recursively scan the directories looking for go code with a recognizable tag // gog:

a source file named src.go with

//go:generate gog

// gog:record
type Foo struct {
	// gog:@required
	name  string
	value int64
}

will generate a file src_gog.go with

// Code generated by gog; DO NOT EDIT.
// Version: x.x.x
package p

import (
	"errors"
	"fmt"
)

// Generated by gog:record

func NewFoo(
	name string,
	value int64,
) (Foo, error) {
	if name == "" {
		return Foo{}, errors.New("Foo.name cannot be empty")
	}
	f := Foo{
		name:  name,
		value: value,
	}

	return f, nil
}

func MustNewFoo(
	name string,
	value int64,
) Foo {
	f, err := NewFoo(
		name,
		value,
	)
	if err != nil {
		panic(err)
	}
	return f
}

func (f Foo) Name() string {
	return f.name
}

func (f Foo) Value() int64 {
	return f.value
}

func (f Foo) IsZero() bool {
	return f == Foo{}
}

func (f Foo) String() string {
	return fmt.Sprintf("Foo{name: %+v, value: %+v}", f.name, f.value)
}

(see the tests in package plugins for more examples)

it is also possible to extend this create your own plugins like the one in here

Guide

gog:allArgsConstructor

generates constructor that includes all the fields

struct comment: gog:allArgsConstructor

field comments:

• gog:@required - if present validates that field is non zero

if the unexported method validate of the strut is present it will additionally call it as part of the constructor. The signature is assumed to be validate() error

gog:getters

generates getters for all fields

struct comment: gog:getters

field comments:

• gog:@ignore - if present the getter for the field will not be generated

gog:record

generates the same as allArgsConstructor and getters with the additional methods IsZero() bool and String() string.

If any of the methods already exist in the initial struct declaration, like IsZero() bool, String() string they will not be generated.

if the unexported method validate of the strut is present it will additionally call it as part of the build call. The signature is assumed to be validate() error

gog:builder

generates a builder function for the annotated struct. No direct setter can be done on the original struct.

If an unexported setter exists it will be set the value on the target struct. If the setter returns an error the Build() function will also return an error.

if the unexported method validate of the strut is present it will additionally call it as part of the build call. The signature is assumed to be validate() error