github.com/operandinc/gqlgen@v0.16.1/main.go

package main

import (
	"bytes"
	"errors"
	"fmt"
	"html/template"
	"io/fs"
	"io/ioutil"
	"log"
	"os"
	"path/filepath"

	"github.com/operandinc/gqlgen/api"
	"github.com/operandinc/gqlgen/codegen/config"
	"github.com/operandinc/gqlgen/graphql"
	"github.com/operandinc/gqlgen/internal/code"
	"github.com/operandinc/gqlgen/plugin/servergen"
	"github.com/urfave/cli/v2"
)

var configTemplate = template.Must(template.New("name").Parse(
	`# Where are all the schema files located? globs are supported eg  src/**/*.graphqls
schema:
  - graph/*.graphqls

# Where should the generated server code go?
exec:
  filename: graph/generated/generated.go
  package: generated

# Uncomment to enable federation
# federation:
#   filename: graph/generated/federation.go
#   package: generated

# Where should any generated models go?
model:
  filename: graph/model/models_gen.go
  package: model

# Where should the resolver implementations go?
resolver:
  layout: follow-schema
  dir: graph
  package: graph

# Optional: turn on use ` + "`" + `gqlgen:"fieldName"` + "`" + ` tags in your models
# struct_tag: json

# Optional: turn on to use []Thing instead of []*Thing
# omit_slice_element_pointers: false

# Optional: set to speed up generation time by not performing a final validation pass.
# skip_validation: true

# gqlgen will search for any type names in the schema in these go packages
# if they match it will use them, otherwise it will generate them.
autobind:
#  - "{{.}}/graph/model"

# This section declares type mapping between the GraphQL and go type systems
#
# The first line in each type will be used as defaults for resolver arguments and
# modelgen, the others will be allowed when binding to fields. Configure them to
# your liking
models:
  ID:
    model:
      - github.com/operandinc/gqlgen/graphql.ID
      - github.com/operandinc/gqlgen/graphql.Int
      - github.com/operandinc/gqlgen/graphql.Int64
      - github.com/operandinc/gqlgen/graphql.Int32
  Int:
    model:
      - github.com/operandinc/gqlgen/graphql.Int
      - github.com/operandinc/gqlgen/graphql.Int64
      - github.com/operandinc/gqlgen/graphql.Int32
`))

var schemaDefault = `# GraphQL schema example
#
# https://gqlgen.com/getting-started/

type Todo {
  id: ID!
  text: String!
  done: Boolean!
  user: User!
}

type User {
  id: ID!
  name: String!
}

type Query {
  todos: [Todo!]!
}

input NewTodo {
  text: String!
  userId: String!
}

type Mutation {
  createTodo(input: NewTodo!): Todo!
}
`

func executeConfigTemplate(pkgName string) string {
	var buf bytes.Buffer
	if err := configTemplate.Execute(&buf, pkgName); err != nil {
		panic(err)
	}

	return buf.String()
}

func fileExists(filename string) bool {
	_, err := os.Stat(filename)
	return !errors.Is(err, fs.ErrNotExist)
}

func initFile(filename, contents string) error {
	if err := os.MkdirAll(filepath.Dir(filename), 0o755); err != nil {
		return fmt.Errorf("unable to create directory for file '%s': %w\n", filename, err)
	}
	if err := ioutil.WriteFile(filename, []byte(contents), 0o644); err != nil {
		return fmt.Errorf("unable to write file '%s': %w\n", filename, err)
	}

	return nil
}

var initCmd = &cli.Command{
	Name:  "init",
	Usage: "create a new gqlgen project",
	Flags: []cli.Flag{
		&cli.BoolFlag{Name: "verbose, v", Usage: "show logs"},
		&cli.StringFlag{Name: "config, c", Usage: "the config filename", Value: "gqlgen.yml"},
		&cli.StringFlag{Name: "server", Usage: "where to write the server stub to", Value: "server.go"},
		&cli.StringFlag{Name: "schema", Usage: "where to write the schema stub to", Value: "graph/schema.graphqls"},
	},
	Action: func(ctx *cli.Context) error {
		configFilename := ctx.String("config")
		serverFilename := ctx.String("server")
		schemaFilename := ctx.String("schema")

		pkgName := code.ImportPathForDir(".")
		if pkgName == "" {
			return fmt.Errorf("unable to determine import path for current directory, you probably need to run go mod init first")
		}

		// check schema and config don't already exist
		for _, filename := range []string{configFilename, schemaFilename, serverFilename} {
			if fileExists(filename) {
				return fmt.Errorf("%s already exists", filename)
			}
		}
		_, err := config.LoadConfigFromDefaultLocations()
		if err == nil {
			return fmt.Errorf("gqlgen.yml already exists in a parent directory\n")
		}

		// create config
		fmt.Println("Creating", configFilename)
		if err := initFile(configFilename, executeConfigTemplate(pkgName)); err != nil {
			return err
		}

		// create schema
		fmt.Println("Creating", schemaFilename)
		if err := initFile(schemaFilename, schemaDefault); err != nil {
			return err
		}

		// create the package directory with a temporary file so that go recognises it as a package
		// and autobinding doesn't error out
		tmpPackageNameFile := "graph/model/_tmp_gqlgen_init.go"
		if err := initFile(tmpPackageNameFile, "package model"); err != nil {
			return err
		}
		defer os.Remove(tmpPackageNameFile)

		var cfg *config.Config
		if cfg, err = config.LoadConfig(configFilename); err != nil {
			panic(err)
		}

		fmt.Println("Creating", serverFilename)
		fmt.Println("Generating...")
		if err := api.Generate(cfg, api.AddPlugin(servergen.New(serverFilename))); err != nil {
			fmt.Fprintln(os.Stderr, err.Error())
		}

		fmt.Printf("\nExec \"go run ./%s\" to start GraphQL server\n", serverFilename)
		return nil
	},
}

var generateCmd = &cli.Command{
	Name:  "generate",
	Usage: "generate a graphql server based on schema",
	Flags: []cli.Flag{
		&cli.BoolFlag{Name: "verbose, v", Usage: "show logs"},
		&cli.StringFlag{Name: "config, c", Usage: "the config filename"},
	},
	Action: func(ctx *cli.Context) error {
		var cfg *config.Config
		var err error
		if configFilename := ctx.String("config"); configFilename != "" {
			cfg, err = config.LoadConfig(configFilename)
			if err != nil {
				return err
			}
		} else {
			cfg, err = config.LoadConfigFromDefaultLocations()
			if errors.Is(err, fs.ErrNotExist) {
				cfg, err = config.LoadDefaultConfig()
			}

			if err != nil {
				return err
			}
		}

		if err = api.Generate(cfg); err != nil {
			return err
		}
		return nil
	},
}

var versionCmd = &cli.Command{
	Name:  "version",
	Usage: "print the version string",
	Action: func(ctx *cli.Context) error {
		fmt.Println(graphql.Version)
		return nil
	},
}

func main() {
	app := cli.NewApp()
	app.Name = "gqlgen"
	app.Usage = generateCmd.Usage
	app.Description = "This is a library for quickly creating strictly typed graphql servers in golang. See https://gqlgen.com/ for a getting started guide."
	app.HideVersion = true
	app.Flags = generateCmd.Flags
	app.Version = graphql.Version
	app.Before = func(context *cli.Context) error {
		if context.Bool("verbose") {
			log.SetFlags(0)
		} else {
			log.SetOutput(ioutil.Discard)
		}
		return nil
	}

	app.Action = generateCmd.Action
	app.Commands = []*cli.Command{
		generateCmd,
		initCmd,
		versionCmd,
	}

	if err := app.Run(os.Args); err != nil {
		fmt.Fprint(os.Stderr, err.Error()+"\n")
		os.Exit(1)
	}
}