DeleteAuthenticationのRPCを追加

db/migrations/000003_add_column_constraints_to_user_authentications.down.sql

@@ -0,0 +1,7 @@
+BEGIN;
+
+ALTER TABLE user_authentications DROP CONSTRAINT uq_user_authentications_provider_social_id;
+
+ALTER TABLE user_authentications DROP CONSTRAINT uq_user_authentications_user_id_provider;
+
+COMMIT;

db/migrations/000003_add_column_constraints_to_user_authentications.up.sql

@@ -0,0 +1,7 @@
+BEGIN;
+
+ALTER TABLE user_authentications ADD CONSTRAINT uq_user_authentications_provider_social_id UNIQUE (provider, social_id);
+
+ALTER TABLE user_authentications ADD CONSTRAINT uq_user_authentications_user_id_provider UNIQUE (user_id, provider);
+
+COMMIT;

entity/error.go

@@ -7,3 +7,5 @@ var ErrUserNotFound = errors.New("user not found")
 var ErrUserAlreadyExists = errors.New("user already exists")
 
 var ErrAuthenticationAlreadyExists = errors.New("authentication already exists")
+
+var ErrAuthenticationNotFound = errors.New("authentication not found")

port/interface.go

@@ -29,4 +29,8 @@ type IRepository interface {
 	// If the user does not exist, return ErrUserNotFound.
 	// If the authentication is already registered, return ErrAuthenticationAlreadyExists.
 	AddAuthentication(ctx context.Context, id string, a *entity.Authentication) error
+
+	// DeleteAuthentication deletes the authentication specified by the given userID and provider.
+	// If the corresponding authentication does not exist, return ErrAuthenticationNotFound.
+	DeleteAuthentication(ctx context.Context, userID string, provider entity.Provider) error
 }

repository/repository.go

@@ -194,6 +194,30 @@ func (r *Repository) AddAuthentication(ctx context.Context, id string, a *entity
 	return nil
 }
 
+func (r *Repository) DeleteAuthentication(ctx context.Context, userID string, provider entity.Provider) error {
+	failed := func(err error) error {
+		return fmt.Errorf("Repository.DeleteAuthentication %q %q -> %w", userID, provider, err)
+	}
+
+	var aid string
+	query := "SELECT id FROM user_authentications WHERE user_id = $1 AND provider = $2"
+	err := r.db.QueryRowContext(ctx, query, userID, provider).Scan(&aid)
+	if err != nil {
+		if err == sql.ErrNoRows {
+			return failed(entity.ErrAuthenticationNotFound)
+		}
+		return failed(err)
+	}
+
+	query = "DELETE FROM user_authentications WHERE id = $1"
+	_, err = r.db.ExecContext(ctx, query, aid)
+	if err != nil {
+		return failed(err)
+	}
+
+	return nil
+}
+
 // getUserIDByAuthentication returns the id of the user authorized by the given authentication.
 // If the corresponding user does not exist, return ErrUserNotFound.
 func (r *Repository) getUserIDByAuthentication(ctx context.Context, a *entity.Authentication) (id string, err error) {

server/converter/error.go

@@ -14,6 +14,8 @@ func ToGRPCError(err error, log func(err error)) error {
 		return status.Error(codes.NotFound, "指定されたユーザーが見つかりませんでした")
 	case errors.Is(err, entity.ErrAuthenticationAlreadyExists):
 		return status.Error(codes.AlreadyExists, "認証情報が既に登録されています")
+	case errors.Is(err, entity.ErrAuthenticationNotFound):
+		return status.Error(codes.NotFound, "指定された認証情報が見つかりませんでした")
 	default:
 		log(err)
 		return status.Error(codes.Internal, "サーバー内で問題が発生しました")

server/pb/UserService.proto

@@ -6,6 +6,11 @@ service UserService {
   rpc AddAuthentication(AddAuthenticationRequest) returns (AddAuthenticationResponse);
   rpc GetUser(GetUserRequest) returns (GetUserResponse);
   rpc DeleteUser(DeleteUserRequest) returns (DeleteUserResponse);
+
+  // 紐付けアカウントが1つだけの場合はエラーになる
+  // 紐付けアカウントが2つ以上の場合は指定された紐付けアカウントの紐付けを解除する（hard delete）
+  // 指定されたプロバイダがユーザーに紐づいていない場合はエラーになる
+  rpc DeleteAuthentication(DeleteAuthenticationRequest) returns (DeleteAuthenticationResponse);
 }
 
 enum Provider {
@@ -29,7 +34,6 @@ message GetOrCreateUserResponse {
 }
 
 message AddAuthenticationRequest {
-
   string id = 1;
   Provider provider = 2;
   string socialId = 3;
@@ -50,4 +54,11 @@ message DeleteUserRequest {
   string id = 1;
 }
 
-message DeleteUserResponse {}
+message DeleteUserResponse {}
+
+message DeleteAuthenticationRequest {
+  string id = 1;
+  Provider provider = 2;
+}
+
+message DeleteAuthenticationResponse {}