[performance] add user cache and database (#879)

* go fmt

* add + use user cache and database

* fix import

* update tests

* remove unused relation

internal/db/bundb/user.go

@@ -0,0 +1,151 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package bundb
+
+import (
+	"context"
+	"time"
+
+	"github.com/superseriousbusiness/gotosocial/internal/cache"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/uptrace/bun"
+)
+
+type userDB struct {
+	conn  *DBConn
+	cache *cache.UserCache
+}
+
+func (u *userDB) newUserQ(user *gtsmodel.User) *bun.SelectQuery {
+	return u.conn.
+		NewSelect().
+		Model(user).
+		Relation("Account")
+}
+
+func (u *userDB) getUser(ctx context.Context, cacheGet func() (*gtsmodel.User, bool), dbQuery func(*gtsmodel.User) error) (*gtsmodel.User, db.Error) {
+	// Attempt to fetch cached user
+	user, cached := cacheGet()
+
+	if !cached {
+		user = &gtsmodel.User{}
+
+		// Not cached! Perform database query
+		err := dbQuery(user)
+		if err != nil {
+			return nil, u.conn.ProcessError(err)
+		}
+
+		// Place in the cache
+		u.cache.Put(user)
+	}
+
+	return user, nil
+}
+
+func (u *userDB) GetUserByID(ctx context.Context, id string) (*gtsmodel.User, db.Error) {
+	return u.getUser(
+		ctx,
+		func() (*gtsmodel.User, bool) {
+			return u.cache.GetByID(id)
+		},
+		func(user *gtsmodel.User) error {
+			return u.newUserQ(user).Where("user.id = ?", id).Scan(ctx)
+		},
+	)
+}
+
+func (u *userDB) GetUserByAccountID(ctx context.Context, accountID string) (*gtsmodel.User, db.Error) {
+	return u.getUser(
+		ctx,
+		func() (*gtsmodel.User, bool) {
+			return u.cache.GetByAccountID(accountID)
+		},
+		func(user *gtsmodel.User) error {
+			return u.newUserQ(user).Where("user.account_id = ?", accountID).Scan(ctx)
+		},
+	)
+}
+
+func (u *userDB) GetUserByEmailAddress(ctx context.Context, emailAddress string) (*gtsmodel.User, db.Error) {
+	return u.getUser(
+		ctx,
+		func() (*gtsmodel.User, bool) {
+			return u.cache.GetByEmail(emailAddress)
+		},
+		func(user *gtsmodel.User) error {
+			return u.newUserQ(user).Where("user.email = ?", emailAddress).Scan(ctx)
+		},
+	)
+}
+
+func (u *userDB) GetUserByConfirmationToken(ctx context.Context, confirmationToken string) (*gtsmodel.User, db.Error) {
+	return u.getUser(
+		ctx,
+		func() (*gtsmodel.User, bool) {
+			return u.cache.GetByConfirmationToken(confirmationToken)
+		},
+		func(user *gtsmodel.User) error {
+			return u.newUserQ(user).Where("user.confirmation_token = ?", confirmationToken).Scan(ctx)
+		},
+	)
+}
+
+func (u *userDB) PutUser(ctx context.Context, user *gtsmodel.User) (*gtsmodel.User, db.Error) {
+	if _, err := u.conn.
+		NewInsert().
+		Model(user).
+		Exec(ctx); err != nil {
+		return nil, u.conn.ProcessError(err)
+	}
+
+	u.cache.Put(user)
+	return user, nil
+}
+
+func (u *userDB) UpdateUser(ctx context.Context, user *gtsmodel.User, columns ...string) (*gtsmodel.User, db.Error) {
+	// Update the user's last-updated
+	user.UpdatedAt = time.Now()
+
+	if _, err := u.conn.
+		NewUpdate().
+		Model(user).
+		WherePK().
+		Column(columns...).
+		Exec(ctx); err != nil {
+		return nil, u.conn.ProcessError(err)
+	}
+
+	u.cache.Invalidate(user.ID)
+	return user, nil
+}
+
+func (u *userDB) DeleteUserByID(ctx context.Context, userID string) db.Error {
+	if _, err := u.conn.
+		NewDelete().
+		Model(&gtsmodel.User{ID: userID}).
+		WherePK().
+		Exec(ctx); err != nil {
+		return u.conn.ProcessError(err)
+	}
+
+	u.cache.Invalidate(userID)
+	return nil
+}