stash/vendor/github.com/Yamashou/gqlgenc/generator/generater.go

package generator

import (
	"context"
	"fmt"

	"github.com/99designs/gqlgen/api"
	"github.com/99designs/gqlgen/plugin"
	"github.com/99designs/gqlgen/plugin/modelgen"
	"github.com/Yamashou/gqlgenc/config"
)

// mutateHook adds the "omitempty" option to optional field from input type model as defined in graphql schema
// For more info see https://github.com/99designs/gqlgen/blob/master/docs/content/recipes/modelgen-hook.md
func mutateHook(cfg *config.Config) func(b *modelgen.ModelBuild) *modelgen.ModelBuild {
	return func(build *modelgen.ModelBuild) *modelgen.ModelBuild {
		for _, model := range build.Models {
			// only handle input type model
			if schemaModel, ok := cfg.GQLConfig.Schema.Types[model.Name]; ok && schemaModel.IsInputType() {
				for _, field := range model.Fields {
					// find field in graphql schema
					for _, def := range schemaModel.Fields {
						if def.Name == field.Name {
							// only add 'omitempty' on optional field as defined in graphql schema
							if !def.Type.NonNull {
								field.Tag = `json:"` + field.Name + `,omitempty"`
							}

							break
						}
					}
				}
			}
		}

		return build
	}
}

func Generate(ctx context.Context, cfg *config.Config, option ...api.Option) error {
	var plugins []plugin.Plugin
	if cfg.Model.IsDefined() {
		p := modelgen.Plugin{
			MutateHook: mutateHook(cfg),
		}
		plugins = append(plugins, &p)
	}
	for _, o := range option {
		o(cfg.GQLConfig, &plugins)
	}

	if err := cfg.LoadSchema(ctx); err != nil {
		return fmt.Errorf("failed to load schema: %w", err)
	}

	if err := cfg.GQLConfig.Init(); err != nil {
		return fmt.Errorf("generating core failed: %w", err)
	}

	for _, p := range plugins {
		if mut, ok := p.(plugin.ConfigMutator); ok {
			err := mut.MutateConfig(cfg.GQLConfig)
			if err != nil {
				return fmt.Errorf("%s failed: %w", p.Name(), err)
			}
		}
	}

	return nil
}