goenv2系に更新して最新のGoをインストール

Golang

チュートリアル

https://zenn.dev/hsaki/books/golang-graphql/viewer/tutorial

既存環境削除

% brew remove go

# GOROOT設定されているか確認
$ echo $GOROOT
# 設定されていたらディレクトリ削除、GOROOT設定されていない場合は不要
$ rm -rf $GOROOT

# GOPATH設定されているか確認
$ echo $GOPATH
# 設定されていたらディレクトリ削除、GOPATH設定されていない場合は不要
$ rm -rf $GOPATH

環境変数削除
# GOROOT,GOPATHの設定箇所削除
$ vi ~/.zshrc

% brew uninstall goenv

$ brew install --HEAD goenv
% goenv -v
goenv 2.0.6

$ brew update && brew upgrade goenv
$ cd $GOENV_ROOT
$ git pull origin master

インストールできるバージョン確認
$ goenv install -l
バージョンを指定してインストール
$ goenv install 1.18

$ goenv global 1.18.10

goenv2系の場合
$ vi ~/.zshrc

以下を追記

export GOENV_ROOT="$HOME/.goenv"
export PATH="$GOENV_ROOT/bin:$PATH"
eval "$(goenv init -)"
export PATH="$GOROOT/bin:$PATH"
export PATH="$PATH:$GOPATH/bin"

$ source ~/.zshrc

% cd /Users/kanehiroyuu/Documents/develop.nosync/study-graphql
% go install github.com/99designs/gqlgen@latest
% gqlgen version
v0.17.30

% go mod init my_gql_server
go: /Users/kanehiroyuu/Documents/develop.nosync/study-graphql/go.mod already exists

% go get -u github.com/99designs/gqlgen
サンプルアプリ作成
% gqlgen init
% go mod tidy

Query
query {
  todos {
    id
    text
    done
    user {
      name
    }
  }
}

Response
{
  "data": {
    "todos": [
      {
        "id": "TODO-1",
        "text": "My Todo 1",
        "done": true,
        "user": {
          "name": "hsaki"
        }
      },
      {
        "id": "TODO-2",
        "text": "My Todo 2",
        "done": false,
        "user": {
          "name": "hsaki"
        }
      }
    ]
  }
}

参考になった

・Interfaceはメソッドの塊です。
・Interfaceが期待するメソッド（例ではFuncA,FuncB）をすべて満たした変数には、自動的にInterfaceが実装されます。
・Interfaceを満たした変数はInterfaceへ代入することができます。

https://cloudsmith.co.jp/blog/backend/go/2021/08/1847845.html

type Hoge interface {
	FuncA()
        FuncB()
}

type Foo struct {}

func (f *Foo) FuncA() {}
func (f *Foo) FuncB() {}

func main() {
        var hoge Hoge
        hoge = Foo{..}       // HogeインターフェースにFoo構造体を代入できる
}

https://github.com/saki-engineering/graphql-sample/blob/main/graph/services/users.go

package services

import (
	"context"

	"github.com/saki-engineering/graphql-sample/graph/db"
	"github.com/saki-engineering/graphql-sample/graph/model"

	"github.com/volatiletech/sqlboiler/v4/boil"
	"github.com/volatiletech/sqlboiler/v4/queries/qm"
)

type userService struct {
	exec boil.ContextExecutor
}

func convertUser(user *db.User) *model.User {
	return &model.User{
		ID:   user.ID,
		Name: user.Name,
	}
}

func convertUserSlice(users db.UserSlice) []*model.User {
	result := make([]*model.User, 0, len(users))
	for _, user := range users {
		result = append(result, convertUser(user))
	}
	return result
}

func (u *userService) GetUserByID(ctx context.Context, id string) (*model.User, error) {
	user, err := db.FindUser(ctx, u.exec, id,
		db.UserTableColumns.ID, db.UserTableColumns.Name,
	)
	if err != nil {
		return nil, err
	}
	return convertUser(user), nil
}

func (u *userService) GetUserByName(ctx context.Context, name string) (*model.User, error) {
	user, err := db.Users(
		qm.Select(db.UserTableColumns.ID, db.UserTableColumns.Name),
		db.UserWhere.Name.EQ(name),
		// qm.Where("name = ?", name),
	).One(ctx, u.exec)
	if err != nil {
		return nil, err
	}
	return convertUser(user), nil
}

func (u *userService) ListUsersByID(ctx context.Context, IDs []string) ([]*model.User, error) {
	users, err := db.Users(
		qm.Select(db.UserTableColumns.ID, db.UserTableColumns.Name),
		db.UserWhere.ID.IN(IDs),
	).All(ctx, u.exec)
	if err != nil {
		return nil, err
	}
	return convertUserSlice(users), nil
}

https://github.com/saki-engineering/graphql-sample/blob/main/graph/services/service.go

package services

import (
	"context"

	"github.com/saki-engineering/graphql-sample/graph/model"

	"github.com/volatiletech/sqlboiler/v4/boil"
)

//go:generate mockgen -source=$GOFILE -package=$GOPACKAGE -destination=../../mock/$GOPACKAGE/service_mock.go
type Services interface {
	UserService
	RepoService
	IssueService
	PullRequestService
	ProjectService
	ProjectItemService
}

type UserService interface {
	GetUserByID(ctx context.Context, id string) (*model.User, error)
	GetUserByName(ctx context.Context, name string) (*model.User, error)
	ListUsersByID(ctx context.Context, IDs []string) ([]*model.User, error)
}

type RepoService interface {
	GetRepoByID(ctx context.Context, id string) (*model.Repository, error)
	GetRepoByFullName(ctx context.Context, owner, name string) (*model.Repository, error)
}

type IssueService interface {
	GetIssueByID(ctx context.Context, id string) (*model.Issue, error)
	GetIssueByRepoAndNumber(ctx context.Context, repoID string, number int) (*model.Issue, error)
	ListIssueInRepository(ctx context.Context, repoID string, after *string, before *string, first *int, last *int) (*model.IssueConnection, error)
}

type PullRequestService interface {
	GetPullRequestByID(ctx context.Context, id string) (*model.PullRequest, error)
	GetPullRequestByRepoAndNumber(ctx context.Context, repoID string, number int) (*model.PullRequest, error)
	ListPullRequestInRepository(ctx context.Context, repoID string, after *string, before *string, first *int, last *int) (*model.PullRequestConnection, error)
}

type ProjectService interface {
	GetProjectByID(ctx context.Context, id string) (*model.ProjectV2, error)
	GetProjectByOwnerAndNumber(ctx context.Context, ownerID string, number int) (*model.ProjectV2, error)
	ListProjectByOwner(ctx context.Context, ownerID string, after *string, before *string, first *int, last *int) (*model.ProjectV2Connection, error)
}

type ProjectItemService interface {
	GetProjectItemByID(ctx context.Context, id string) (*model.ProjectV2Item, error)
	ListProjectItemOwnedByProject(ctx context.Context, projectID string, after *string, before *string, first *int, last *int) (*model.ProjectV2ItemConnection, error)
	ListProjectItemOwnedByIssue(ctx context.Context, issueID string, after *string, before *string, first *int, last *int) (*model.ProjectV2ItemConnection, error)
	ListProjectItemOwnedByPullRequest(ctx context.Context, pullRequestID string, after *string, before *string, first *int, last *int) (*model.ProjectV2ItemConnection, error)
	AddIssueInProjectV2(ctx context.Context, projectID, issueID string) (*model.ProjectV2Item, error)
	AddPullRequestInProjectV2(ctx context.Context, projectID, pullRequestID string) (*model.ProjectV2Item, error)
}

type services struct {
	*userService
	*repoService
	*issueService
	*pullRequestService
	*projectService
	*projectItemService
}

func New(exec boil.ContextExecutor) Services {
	return &services{
		userService:        &userService{exec: exec},
		repoService:        &repoService{exec: exec},
		issueService:       &issueService{exec: exec},
		pullRequestService: &pullRequestService{exec: exec},
		projectService:     &projectService{exec: exec},
		projectItemService: &projectItemService{exec: exec},
	}
}