Govy library is released along with a binary which comes as a sidekick.

Currently it has a single subcommand, inferpath.

Usage of govy:
  govy <subcommand> [flags]
Subcommands:
  inferpath

In order to install govy binary, run:

go install github.com/nobl9/govy/cmd/govy@latest

Alternatively you can use tools.go file, as described in Go wiki.

//go:build tools

package main

import (
	_ "github.com/nobl9/govy/cmd/govy"
)

inferpath is a code generator that can be used to infer relative property paths for govy getter expressions. It searches for invocations of govy.PropertyRules constructors, like govy.For, and follows the AST to find the path returned from govy.PropertyGetter.

It produces a single file with code registering all inferred paths. It is important to make sure the generated file is loaded BEFORE any govy.PropertyRules constructors are called. Otherwise the inferred paths will not be available to the govy package.

The generated paths are relative fragments such as name or students[0].index. They do not include a leading $ root segment.

To generate a file with inferred paths, run the following command from the root of your project:

govy inferpath -dir <directory> -pkg <package> -filename <filename>

The following flags are available:

Usage of govy inferpath:
  -dir string
        directory path to save the generated file
  -filename string
        generated file name (default "govy_inferred_paths.go")
  -pkg string
        package name of the generated file

// Code generated by "govy inferpath -dir . -pkg main"; DO NOT EDIT.

package main

import (
	"github.com/nobl9/govy/pkg/govyconfig"
	"github.com/nobl9/govy/pkg/jsonpath"
)

func init() {
	inferredPaths := map[string]govyconfig.InferredPath{
		"student/nested.go:13": {
			Path: jsonpath.Parse("name"),
			File: "student/nested.go",
			Line: 13,
		},
		"university/university.go:13": {
			Path: jsonpath.Parse("name"),
			File: "university/university.go",
			Line: 13,
		},
		"validation.go:11": {
			Path: jsonpath.Parse("name"),
			File: "validation.go",
			Line: 11,
		},
		"validation.go:13": {
			Path: jsonpath.Parse("university.name"),
			File: "validation.go",
			Line: 13,
		},
		"validation.go:15": {
			Path: jsonpath.Parse("university"),
			File: "validation.go",
			Line: 15,
		},
	}
	for _, path := range inferredPaths {
		govyconfig.SetInferredPath(path)
	}
}