Improve storage module

12 files changed, 499 insertions, 311 deletions

diff --git a/storage/category.go b/storage/category.go
index 72ba24b..07206c0 100644
--- a/storage/category.go
+++ b/storage/category.go
@@ -14,18 +14,18 @@ import (
 
 // AnotherCategoryExists checks if another category exists with the same title.
 func (s *Storage) AnotherCategoryExists(userID, categoryID int64, title string) bool {
-	var result int
-	query := `SELECT count(*) as c FROM categories WHERE user_id=$1 AND id != $2 AND title=$3`
+	var result bool
+	query := `SELECT true FROM categories WHERE user_id=$1 AND id != $2 AND title=$3`
 	s.db.QueryRow(query, userID, categoryID, title).Scan(&result)
-	return result >= 1
+	return result
 }
 
 // CategoryExists checks if the given category exists into the database.
 func (s *Storage) CategoryExists(userID, categoryID int64) bool {
-	var result int
-	query := `SELECT count(*) as c FROM categories WHERE user_id=$1 AND id=$2`
+	var result bool
+	query := `SELECT true FROM categories WHERE user_id=$1 AND id=$2`
 	s.db.QueryRow(query, userID, categoryID).Scan(&result)
-	return result >= 1
+	return result
 }
 
 // Category returns a category from the database.
@@ -34,28 +34,32 @@ func (s *Storage) Category(userID, categoryID int64) (*model.Category, error) {
 
 	query := `SELECT id, user_id, title FROM categories WHERE user_id=$1 AND id=$2`
 	err := s.db.QueryRow(query, userID, categoryID).Scan(&category.ID, &category.UserID, &category.Title)
-	if err == sql.ErrNoRows {
+
+	switch {
+	case err == sql.ErrNoRows:
 		return nil, nil
-	} else if err != nil {
-		return nil, fmt.Errorf("unable to fetch category: %v", err)
+	case err != nil:
+		return nil, fmt.Errorf(`store: unable to fetch category: %v`, err)
+	default:
+		return &category, nil
 	}
-
-	return &category, nil
 }
 
 // FirstCategory returns the first category for the given user.
 func (s *Storage) FirstCategory(userID int64) (*model.Category, error) {
-	var category model.Category
-
 	query := `SELECT id, user_id, title FROM categories WHERE user_id=$1 ORDER BY title ASC LIMIT 1`
+
+	var category model.Category
 	err := s.db.QueryRow(query, userID).Scan(&category.ID, &category.UserID, &category.Title)
-	if err == sql.ErrNoRows {
+
+	switch {
+	case err == sql.ErrNoRows:
 		return nil, nil
-	} else if err != nil {
-		return nil, fmt.Errorf("unable to fetch category: %v", err)
+	case err != nil:
+		return nil, fmt.Errorf(`store: unable to fetch category: %v`, err)
+	default:
+		return &category, nil
 	}
-
-	return &category, nil
 }
 
 // CategoryByTitle finds a category by the title.
@@ -64,13 +68,15 @@ func (s *Storage) CategoryByTitle(userID int64, title string) (*model.Category,
 
 	query := `SELECT id, user_id, title FROM categories WHERE user_id=$1 AND title=$2`
 	err := s.db.QueryRow(query, userID, title).Scan(&category.ID, &category.UserID, &category.Title)
-	if err == sql.ErrNoRows {
+
+	switch {
+	case err == sql.ErrNoRows:
 		return nil, nil
-	} else if err != nil {
-		return nil, fmt.Errorf("Unable to fetch category: %v", err)
+	case err != nil:
+		return nil, fmt.Errorf(`store: unable to fetch category: %v`, err)
+	default:
+		return &category, nil
 	}
-
-	return &category, nil
 }
 
 // Categories returns all categories that belongs to the given user.
@@ -78,7 +84,7 @@ func (s *Storage) Categories(userID int64) (model.Categories, error) {
 	query := `SELECT id, user_id, title FROM categories WHERE user_id=$1 ORDER BY title ASC`
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("Unable to fetch categories: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch categories: %v`, err)
 	}
 	defer rows.Close()
 
@@ -86,7 +92,7 @@ func (s *Storage) Categories(userID int64) (model.Categories, error) {
 	for rows.Next() {
 		var category model.Category
 		if err := rows.Scan(&category.ID, &category.UserID, &category.Title); err != nil {
-			return nil, fmt.Errorf("Unable to fetch categories row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch category row: %v`, err)
 		}
 
 		categories = append(categories, &category)
@@ -97,15 +103,21 @@ func (s *Storage) Categories(userID int64) (model.Categories, error) {
 
 // CategoriesWithFeedCount returns all categories with the number of feeds.
 func (s *Storage) CategoriesWithFeedCount(userID int64) (model.Categories, error) {
-	query := `SELECT
-		c.id, c.user_id, c.title,
-		(SELECT count(*) FROM feeds WHERE feeds.category_id=c.id) AS count
-		FROM categories c WHERE user_id=$1
-		ORDER BY c.title ASC`
+	query := `
+		SELECT
+			c.id,
+			c.user_id,
+			c.title,
+			(SELECT count(*) FROM feeds WHERE feeds.category_id=c.id) AS count
+		FROM categories c
+		WHERE
+			user_id=$1
+		ORDER BY c.title ASC
+	`
 
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("Unable to fetch categories: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch categories: %v`, err)
 	}
 	defer rows.Close()
 
@@ -113,7 +125,7 @@ func (s *Storage) CategoriesWithFeedCount(userID int64) (model.Categories, error
 	for rows.Next() {
 		var category model.Category
 		if err := rows.Scan(&category.ID, &category.UserID, &category.Title, &category.FeedCount); err != nil {
-			return nil, fmt.Errorf("Unable to fetch categories row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch category row: %v`, err)
 		}
 
 		categories = append(categories, &category)
@@ -126,10 +138,11 @@ func (s *Storage) CategoriesWithFeedCount(userID int64) (model.Categories, error
 func (s *Storage) CreateCategory(category *model.Category) error {
 	query := `
 		INSERT INTO categories
-		(user_id, title)
+			(user_id, title)
 		VALUES
-		($1, $2)
-		RETURNING id
+			($1, $2)
+		RETURNING
+			id
 	`
 	err := s.db.QueryRow(
 		query,
@@ -138,7 +151,7 @@ func (s *Storage) CreateCategory(category *model.Category) error {
 	).Scan(&category.ID)
 
 	if err != nil {
-		return fmt.Errorf("Unable to create category: %v", err)
+		return fmt.Errorf(`store: unable to create category: %v`, err)
 	}
 
 	return nil
@@ -155,7 +168,7 @@ func (s *Storage) UpdateCategory(category *model.Category) error {
 	)
 
 	if err != nil {
-		return fmt.Errorf("Unable to update category: %v", err)
+		return fmt.Errorf(`store: unable to update category: %v`, err)
 	}
 
 	return nil
@@ -163,18 +176,19 @@ func (s *Storage) UpdateCategory(category *model.Category) error {
 
 // RemoveCategory deletes a category.
 func (s *Storage) RemoveCategory(userID, categoryID int64) error {
-	result, err := s.db.Exec("DELETE FROM categories WHERE id = $1 AND user_id = $2", categoryID, userID)
+	query := `DELETE FROM categories WHERE id = $1 AND user_id = $2`
+	result, err := s.db.Exec(query, categoryID, userID)
 	if err != nil {
-		return fmt.Errorf("Unable to remove this category: %v", err)
+		return fmt.Errorf(`store: unable to remove this category: %v`, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("Unable to remove this category: %v", err)
+		return fmt.Errorf(`store: unable to remove this category: %v`, err)
 	}
 
 	if count == 0 {
-		return errors.New("no category has been removed")
+		return errors.New(`store: no category has been removed`)
 	}
 
 	return nil
diff --git a/storage/enclosure.go b/storage/enclosure.go
index 604dc02..6684c78 100644
--- a/storage/enclosure.go
+++ b/storage/enclosure.go
@@ -12,14 +12,24 @@ import (
 
 // GetEnclosures returns all attachments for the given entry.
 func (s *Storage) GetEnclosures(entryID int64) (model.EnclosureList, error) {
-	query := `SELECT
-		id, user_id, entry_id, url, size, mime_type
-		FROM enclosures
-		WHERE entry_id = $1 ORDER BY id ASC`
+	query := `
+		SELECT
+			id,
+			user_id,
+			entry_id,
+			url,
+			size,
+			mime_type
+		FROM
+			enclosures
+		WHERE
+			entry_id = $1
+		ORDER BY id ASC
+	`
 
 	rows, err := s.db.Query(query, entryID)
 	if err != nil {
-		return nil, fmt.Errorf("unable to get enclosures: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch enclosures: %v`, err)
 	}
 	defer rows.Close()
 
@@ -36,7 +46,7 @@ func (s *Storage) GetEnclosures(entryID int64) (model.EnclosureList, error) {
 		)
 
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch enclosure row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch enclosure row: %v`, err)
 		}
 
 		enclosures = append(enclosures, &enclosure)
@@ -49,10 +59,11 @@ func (s *Storage) GetEnclosures(entryID int64) (model.EnclosureList, error) {
 func (s *Storage) CreateEnclosure(enclosure *model.Enclosure) error {
 	query := `
 		INSERT INTO enclosures
-		(url, size, mime_type, entry_id, user_id)
+			(url, size, mime_type, entry_id, user_id)
 		VALUES
-		($1, $2, $3, $4, $5)
-		RETURNING id
+			($1, $2, $3, $4, $5)
+		RETURNING
+			id
 	`
 	err := s.db.QueryRow(
 		query,
@@ -64,7 +75,7 @@ func (s *Storage) CreateEnclosure(enclosure *model.Enclosure) error {
 	).Scan(&enclosure.ID)
 
 	if err != nil {
-		return fmt.Errorf("unable to create enclosure %q: %v", enclosure.URL, err)
+		return fmt.Errorf(`store: unable to create enclosure %q: %v`, enclosure.URL, err)
 	}
 
 	return nil
diff --git a/storage/entry.go b/storage/entry.go
index f36bcbe..9a717eb 100644
--- a/storage/entry.go
+++ b/storage/entry.go
@@ -22,7 +22,7 @@ func (s *Storage) CountUnreadEntries(userID int64) int {
 
 	n, err := builder.CountEntries()
 	if err != nil {
-		logger.Error("unable to count unread entries for user #%d: %v", userID, err)
+		logger.Error(`store: unable to count unread entries for user #%d: %v`, userID, err)
 		return 0
 	}
 
@@ -41,21 +41,32 @@ func (s *Storage) UpdateEntryContent(entry *model.Entry) error {
 		return err
 	}
 
-	_, err = tx.Exec(`UPDATE entries SET content=$1 WHERE id=$2 AND user_id=$3`, entry.Content, entry.ID, entry.UserID)
+	query := `
+		UPDATE
+			entries
+		SET
+			content=$1
+		WHERE
+			id=$2 AND user_id=$3
+	`
+	_, err = tx.Exec(query, entry.Content, entry.ID, entry.UserID)
 	if err != nil {
 		tx.Rollback()
-		return fmt.Errorf(`unable to update content of entry #%d: %v`, entry.ID, err)
+		return fmt.Errorf(`store: unable to update content of entry #%d: %v`, entry.ID, err)
 	}
 
-	query := `
-		UPDATE entries
-		SET document_vectors = setweight(to_tsvector(substring(coalesce(title, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce(content, '') for 1000000)), 'B')
-		WHERE id=$1 AND user_id=$2
+	query = `
+		UPDATE
+			entries
+		SET
+			document_vectors = setweight(to_tsvector(substring(coalesce(title, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce(content, '') for 1000000)), 'B')
+		WHERE
+			id=$1 AND user_id=$2
 	`
 	_, err = tx.Exec(query, entry.ID, entry.UserID)
 	if err != nil {
 		tx.Rollback()
-		return fmt.Errorf(`unable to update content of entry #%d: %v`, entry.ID, err)
+		return fmt.Errorf(`store: unable to update content of entry #%d: %v`, entry.ID, err)
 	}
 
 	return tx.Commit()
@@ -65,10 +76,11 @@ func (s *Storage) UpdateEntryContent(entry *model.Entry) error {
 func (s *Storage) createEntry(entry *model.Entry) error {
 	query := `
 		INSERT INTO entries
-		(title, hash, url, comments_url, published_at, content, author, user_id, feed_id, document_vectors)
+			(title, hash, url, comments_url, published_at, content, author, user_id, feed_id, document_vectors)
 		VALUES
-		($1, $2, $3, $4, $5, $6, $7, $8, $9, setweight(to_tsvector(substring(coalesce($1, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce($6, '') for 1000000)), 'B'))
-		RETURNING id, status
+			($1, $2, $3, $4, $5, $6, $7, $8, $9, setweight(to_tsvector(substring(coalesce($1, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce($6, '') for 1000000)), 'B'))
+		RETURNING
+			id, status
 	`
 	err := s.db.QueryRow(
 		query,
@@ -84,7 +96,7 @@ func (s *Storage) createEntry(entry *model.Entry) error {
 	).Scan(&entry.ID, &entry.Status)
 
 	if err != nil {
-		return fmt.Errorf("Unable to create entry %q (feed #%d): %v", entry.URL, entry.FeedID, err)
+		return fmt.Errorf(`store: unable to create entry %q (feed #%d): %v`, entry.URL, entry.FeedID, err)
 	}
 
 	for i := 0; i < len(entry.Enclosures); i++ {
@@ -104,11 +116,19 @@ func (s *Storage) createEntry(entry *model.Entry) error {
 // it default to time.Now() which could change the order of items on the history page.
 func (s *Storage) updateEntry(entry *model.Entry) error {
 	query := `
-		UPDATE entries SET
-		title=$1, url=$2, comments_url=$3, content=$4, author=$5,
-		document_vectors = setweight(to_tsvector(substring(coalesce($1, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce($4, '') for 1000000)), 'B')
-		WHERE user_id=$6 AND feed_id=$7 AND hash=$8
-		RETURNING id
+		UPDATE
+			entries
+		SET
+			title=$1,
+			url=$2,
+			comments_url=$3,
+			content=$4,
+			author=$5,
+			document_vectors = setweight(to_tsvector(substring(coalesce($1, '') for 1000000)), 'A') || setweight(to_tsvector(substring(coalesce($4, '') for 1000000)), 'B')
+		WHERE
+			user_id=$6 AND feed_id=$7 AND hash=$8
+		RETURNING
+			id
 	`
 	err := s.db.QueryRow(
 		query,
@@ -123,7 +143,7 @@ func (s *Storage) updateEntry(entry *model.Entry) error {
 	).Scan(&entry.ID)
 
 	if err != nil {
-		return fmt.Errorf(`unable to update entry %q: %v`, entry.URL, err)
+		return fmt.Errorf(`store: unable to update entry %q: %v`, entry.URL, err)
 	}
 
 	for _, enclosure := range entry.Enclosures {
@@ -145,12 +165,15 @@ func (s *Storage) entryExists(entry *model.Entry) bool {
 // cleanupEntries deletes from the database entries marked as "removed" and not visible anymore in the feed.
 func (s *Storage) cleanupEntries(feedID int64, entryHashes []string) error {
 	query := `
-		DELETE FROM entries
-		WHERE feed_id=$1 AND
-		id IN (SELECT id FROM entries WHERE feed_id=$2 AND status=$3 AND NOT (hash=ANY($4)))
+		DELETE FROM
+			entries
+		WHERE
+			feed_id=$1
+		AND
+			id IN (SELECT id FROM entries WHERE feed_id=$2 AND status=$3 AND NOT (hash=ANY($4)))
 	`
 	if _, err := s.db.Exec(query, feedID, feedID, model.EntryStatusRemoved, pq.Array(entryHashes)); err != nil {
-		return fmt.Errorf("unable to cleanup entries: %v", err)
+		return fmt.Errorf(`store: unable to cleanup entries: %v`, err)
 	}
 
 	return nil
@@ -179,7 +202,7 @@ func (s *Storage) UpdateEntries(userID, feedID int64, entries model.Entries, upd
 	}
 
 	if err := s.cleanupEntries(feedID, entryHashes); err != nil {
-		logger.Error("[Storage:CleanupEntries] feed #%d: %v", feedID, err)
+		logger.Error(`store: feed #%d: %v`, feedID, err)
 	}
 
 	return nil
@@ -190,12 +213,17 @@ func (s *Storage) ArchiveEntries(days int) error {
 	if days < 0 {
 		return nil
 	}
-	query := fmt.Sprintf(`
-			UPDATE entries SET status='removed'
-			WHERE id=ANY(SELECT id FROM entries WHERE status='read' AND starred is false AND published_at < now () - '%d days'::interval LIMIT 5000)
-		`, days)
-	if _, err := s.db.Exec(query); err != nil {
-		return fmt.Errorf("unable to archive read entries: %v", err)
+
+	query := `
+		UPDATE
+			entries
+		SET
+			status='removed'
+		WHERE
+			id=ANY(SELECT id FROM entries WHERE status='read' AND starred is false AND published_at < now () - '%d days'::interval LIMIT 5000)
+	`
+	if _, err := s.db.Exec(fmt.Sprintf(query, days)); err != nil {
+		return fmt.Errorf(`store: unable to archive read entries: %v`, err)
 	}
 
 	return nil
@@ -206,16 +234,16 @@ func (s *Storage) SetEntriesStatus(userID int64, entryIDs []int64, status string
 	query := `UPDATE entries SET status=$1 WHERE user_id=$2 AND id=ANY($3)`
 	result, err := s.db.Exec(query, status, userID, pq.Array(entryIDs))
 	if err != nil {
-		return fmt.Errorf("unable to update entries statuses %v: %v", entryIDs, err)
+		return fmt.Errorf(`store: unable to update entries statuses %v: %v`, entryIDs, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to update these entries %v: %v", entryIDs, err)
+		return fmt.Errorf(`store: unable to update these entries %v: %v`, entryIDs, err)
 	}
 
 	if count == 0 {
-		return errors.New("nothing has been updated")
+		return errors.New(`store: nothing has been updated`)
 	}
 
 	return nil
@@ -226,16 +254,16 @@ func (s *Storage) ToggleBookmark(userID int64, entryID int64) error {
 	query := `UPDATE entries SET starred = NOT starred WHERE user_id=$1 AND id=$2`
 	result, err := s.db.Exec(query, userID, entryID)
 	if err != nil {
-		return fmt.Errorf("unable to toggle bookmark flag for entry #%d: %v", entryID, err)
+		return fmt.Errorf(`store: unable to toggle bookmark flag for entry #%d: %v`, entryID, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to toogle bookmark flag for entry #%d: %v", entryID, err)
+		return fmt.Errorf(`store: unable to toogle bookmark flag for entry #%d: %v`, entryID, err)
 	}
 
 	if count == 0 {
-		return errors.New("nothing has been updated")
+		return errors.New(`store: nothing has been updated`)
 	}
 
 	return nil
@@ -246,7 +274,7 @@ func (s *Storage) FlushHistory(userID int64) error {
 	query := `UPDATE entries SET status=$1 WHERE user_id=$2 AND status=$3 AND starred='f'`
 	_, err := s.db.Exec(query, model.EntryStatusRemoved, userID, model.EntryStatusRead)
 	if err != nil {
-		return fmt.Errorf("unable to flush history: %v", err)
+		return fmt.Errorf(`store: unable to flush history: %v`, err)
 	}
 
 	return nil
@@ -257,7 +285,7 @@ func (s *Storage) MarkAllAsRead(userID int64) error {
 	query := `UPDATE entries SET status=$1 WHERE user_id=$2 AND status=$3`
 	result, err := s.db.Exec(query, model.EntryStatusRead, userID, model.EntryStatusUnread)
 	if err != nil {
-		return fmt.Errorf("unable to mark all entries as read: %v", err)
+		return fmt.Errorf(`store: unable to mark all entries as read: %v`, err)
 	}
 
 	count, _ := result.RowsAffected()
@@ -269,14 +297,16 @@ func (s *Storage) MarkAllAsRead(userID int64) error {
 // MarkFeedAsRead updates all feed entries to the read status.
 func (s *Storage) MarkFeedAsRead(userID, feedID int64, before time.Time) error {
 	query := `
-		UPDATE entries
-		SET status=$1
-		WHERE user_id=$2 AND feed_id=$3 AND status=$4 AND published_at < $5
+		UPDATE
+			entries
+		SET
+			status=$1
+		WHERE
+			user_id=$2 AND feed_id=$3 AND status=$4 AND published_at < $5
 	`
-
 	result, err := s.db.Exec(query, model.EntryStatusRead, userID, feedID, model.EntryStatusUnread, before)
 	if err != nil {
-		return fmt.Errorf("unable to mark feed entries as read: %v", err)
+		return fmt.Errorf(`store: unable to mark feed entries as read: %v`, err)
 	}
 
 	count, _ := result.RowsAffected()
@@ -288,15 +318,22 @@ func (s *Storage) MarkFeedAsRead(userID, feedID int64, before time.Time) error {
 // MarkCategoryAsRead updates all category entries to the read status.
 func (s *Storage) MarkCategoryAsRead(userID, categoryID int64, before time.Time) error {
 	query := `
-		UPDATE entries
-		SET status=$1
+		UPDATE
+			entries
+		SET
+			status=$1
 		WHERE
-		user_id=$2 AND status=$3 AND published_at < $4 AND feed_id IN (SELECT id FROM feeds WHERE user_id=$2 AND category_id=$5)
+			user_id=$2
+		AND
+			status=$3
+		AND
+			published_at < $4
+		AND
+			feed_id IN (SELECT id FROM feeds WHERE user_id=$2 AND category_id=$5)
 	`
-
 	result, err := s.db.Exec(query, model.EntryStatusRead, userID, model.EntryStatusUnread, before, categoryID)
 	if err != nil {
-		return fmt.Errorf("unable to mark category entries as read: %v", err)
+		return fmt.Errorf(`store: unable to mark category entries as read: %v`, err)
 	}
 
 	count, _ := result.RowsAffected()
@@ -307,8 +344,8 @@ func (s *Storage) MarkCategoryAsRead(userID, categoryID int64, before time.Time)
 
 // EntryURLExists returns true if an entry with this URL already exists.
 func (s *Storage) EntryURLExists(feedID int64, entryURL string) bool {
-	var result int
-	query := `SELECT count(*) as c FROM entries WHERE feed_id=$1 AND url=$2`
+	var result bool
+	query := `SELECT true FROM entries WHERE feed_id=$1 AND url=$2`
 	s.db.QueryRow(query, feedID, entryURL).Scan(&result)
-	return result >= 1
+	return result
 }
diff --git a/storage/entry_query_builder.go b/storage/entry_query_builder.go
index c4f6e43..66f1d64 100644
--- a/storage/entry_query_builder.go
+++ b/storage/entry_query_builder.go
@@ -12,7 +12,6 @@ import (
 	"github.com/lib/pq"
 
 	"miniflux.app/model"
-	"miniflux.app/timer"
 	"miniflux.app/timezone"
 )
 
@@ -158,8 +157,6 @@ func (e *EntryQueryBuilder) CountEntries() (count int, err error) {
 	query := `SELECT count(*) FROM entries e LEFT JOIN feeds f ON f.id=e.feed_id WHERE %s`
 	condition := e.buildCondition()
 
-	defer timer.ExecutionTime(time.Now(), fmt.Sprintf("[EntryQueryBuilder:CountEntries] %s, args=%v", condition, e.args))
-
 	err = e.store.db.QueryRow(fmt.Sprintf(query, condition), e.args...).Scan(&count)
 	if err != nil {
 		return 0, fmt.Errorf("unable to count entries: %v", err)
@@ -210,8 +207,6 @@ func (e *EntryQueryBuilder) GetEntries() (model.Entries, error) {
 	sorting := e.buildSorting()
 	query = fmt.Sprintf(query, condition, sorting)
 
-	defer timer.ExecutionTime(time.Now(), fmt.Sprintf("[EntryQueryBuilder:GetEntries] %s, args=%v, sorting=%s", condition, e.args, sorting))
-
 	rows, err := e.store.db.Query(query, e.args...)
 	if err != nil {
 		return nil, fmt.Errorf("unable to get entries: %v", err)
@@ -285,9 +280,6 @@ func (e *EntryQueryBuilder) GetEntryIDs() ([]int64, error) {
 
 	condition := e.buildCondition()
 	query = fmt.Sprintf(query, condition, e.buildSorting())
-	// log.Println(query)
-
-	defer timer.ExecutionTime(time.Now(), fmt.Sprintf("[EntryQueryBuilder:GetEntryIDs] condition=%s, args=%v", condition, e.args))
 
 	rows, err := e.store.db.Query(query, e.args...)
 	if err != nil {
diff --git a/storage/feed.go b/storage/feed.go
index 45ca9be..f6ad021 100644
--- a/storage/feed.go
+++ b/storage/feed.go
@@ -15,18 +15,18 @@ import (
 
 // FeedExists checks if the given feed exists.
 func (s *Storage) FeedExists(userID, feedID int64) bool {
-	var result int
-	query := `SELECT count(*) as c FROM feeds WHERE user_id=$1 AND id=$2`
+	var result bool
+	query := `SELECT true FROM feeds WHERE user_id=$1 AND id=$2`
 	s.db.QueryRow(query, userID, feedID).Scan(&result)
-	return result >= 1
+	return result
 }
 
 // FeedURLExists checks if feed URL already exists.
 func (s *Storage) FeedURLExists(userID int64, feedURL string) bool {
-	var result int
-	query := `SELECT count(*) as c FROM feeds WHERE user_id=$1 AND feed_url=$2`
+	var result bool
+	query := `SELECT true FROM feeds WHERE user_id=$1 AND feed_url=$2`
 	s.db.QueryRow(query, userID, feedURL).Scan(&result)
-	return result >= 1
+	return result
 }
 
 // CountFeeds returns the number of feeds that belongs to the given user.
@@ -42,8 +42,9 @@ func (s *Storage) CountFeeds(userID int64) int {
 
 // CountErrorFeeds returns the number of feeds with parse errors that belong to the given user.
 func (s *Storage) CountErrorFeeds(userID int64) int {
+	query := `SELECT count(*) FROM feeds WHERE user_id=$1 AND parsing_error_count>=$2`
 	var result int
-	err := s.db.QueryRow(`SELECT count(*) FROM feeds WHERE user_id=$1 AND parsing_error_count>=$2`, userID, maxParsingError).Scan(&result)
+	err := s.db.QueryRow(query, userID, maxParsingError).Scan(&result)
 	if err != nil {
 		return 0
 	}
@@ -54,25 +55,40 @@ func (s *Storage) CountErrorFeeds(userID int64) int {
 // Feeds returns all feeds of the given user.
 func (s *Storage) Feeds(userID int64) (model.Feeds, error) {
 	feeds := make(model.Feeds, 0)
-	query := `SELECT
-		f.id, f.feed_url, f.site_url, f.title, f.etag_header, f.last_modified_header,
-		f.user_id, f.checked_at at time zone u.timezone,
-		f.parsing_error_count, f.parsing_error_msg,
-		f.scraper_rules, f.rewrite_rules, f.crawler, f.user_agent,
-		f.username, f.password, f.disabled,
-		f.category_id, c.title as category_title,
-		fi.icon_id,
-		u.timezone
+	query := `
+		SELECT
+			f.id,
+			f.feed_url,
+			f.site_url,
+			f.title,
+			f.etag_header,
+			f.last_modified_header,
+			f.user_id,
+			f.checked_at at time zone u.timezone,
+			f.parsing_error_count,
+			f.parsing_error_msg,
+			f.scraper_rules,
+			f.rewrite_rules,
+			f.crawler,
+			f.user_agent,
+			f.username,
+			f.password,
+			f.disabled,
+			f.category_id,
+			c.title as category_title,
+			fi.icon_id,
+			u.timezone
 		FROM feeds f
 		LEFT JOIN categories c ON c.id=f.category_id
 		LEFT JOIN feed_icons fi ON fi.feed_id=f.id
 		LEFT JOIN users u ON u.id=f.user_id
-		WHERE f.user_id=$1
-		ORDER BY f.parsing_error_count DESC, lower(f.title) ASC`
-
+		WHERE
+			f.user_id=$1
+		ORDER BY f.parsing_error_count DESC, lower(f.title) ASC
+	`
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch feeds: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch feeds: %v`, err)
 	}
 	defer rows.Close()
 
@@ -107,7 +123,7 @@ func (s *Storage) Feeds(userID int64) (model.Feeds, error) {
 		)
 
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch feeds row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch feeds row: %v`, err)
 		}
 
 		if iconID != nil {
@@ -124,27 +140,35 @@ func (s *Storage) Feeds(userID int64) (model.Feeds, error) {
 // FeedsWithCounters returns all feeds of the given user with counters of read and unread entries.
 func (s *Storage) FeedsWithCounters(userID int64) (model.Feeds, error) {
 	feeds := make(model.Feeds, 0)
-	query := `SELECT
-		f.id, f.feed_url, f.site_url, f.title, f.etag_header, f.last_modified_header,
-		f.user_id, f.checked_at at time zone u.timezone,
-		f.parsing_error_count, f.parsing_error_msg,
-		f.scraper_rules, f.rewrite_rules, f.crawler, f.user_agent,
-		f.username, f.password, f.disabled,
-		f.category_id, c.title as category_title,
-		fi.icon_id,
-		u.timezone,
-        (SELECT count(*) FROM entries WHERE entries.feed_id=f.id AND status='unread') as unread_count,
-        (SELECT count(*) FROM entries WHERE entries.feed_id=f.id AND status='read') as read_count
+	query := `
+		SELECT
+			f.id,
+			f.feed_url,
+			f.site_url,
+			f.title,
+			f.etag_header,
+			f.last_modified_header,
+			f.user_id,
+			f.checked_at at time zone u.timezone,
+			f.parsing_error_count, f.parsing_error_msg,
+			f.scraper_rules, f.rewrite_rules, f.crawler, f.user_agent,
+			f.username, f.password, f.disabled,
+			f.category_id, c.title as category_title,
+			fi.icon_id,
+			u.timezone,
+			(SELECT count(*) FROM entries WHERE entries.feed_id=f.id AND status='unread') as unread_count,
+			(SELECT count(*) FROM entries WHERE entries.feed_id=f.id AND status='read') as read_count
 		FROM feeds f
 		LEFT JOIN categories c ON c.id=f.category_id
 		LEFT JOIN feed_icons fi ON fi.feed_id=f.id
 		LEFT JOIN users u ON u.id=f.user_id
-		WHERE f.user_id=$1
-		ORDER BY f.parsing_error_count DESC, unread_count DESC, lower(f.title) ASC`
-
+		WHERE
+			f.user_id=$1
+		ORDER BY f.parsing_error_count DESC, unread_count DESC, lower(f.title) ASC
+	`
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch feeds: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch feeds: %v`, err)
 	}
 	defer rows.Close()
 
@@ -181,7 +205,7 @@ func (s *Storage) FeedsWithCounters(userID int64) (model.Feeds, error) {
 		)
 
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch feeds row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch feeds row: %v`, err)
 		}
 
 		if iconID != nil {
@@ -204,19 +228,33 @@ func (s *Storage) FeedByID(userID, feedID int64) (*model.Feed, error) {
 
 	query := `
 		SELECT
-		f.id, f.feed_url, f.site_url, f.title, f.etag_header, f.last_modified_header,
-		f.user_id, f.checked_at at time zone u.timezone,
-		f.parsing_error_count, f.parsing_error_msg,
-		f.scraper_rules, f.rewrite_rules, f.crawler, f.user_agent,
-		f.username, f.password, f.disabled,
-		f.category_id, c.title as category_title,
-		fi.icon_id,
-		u.timezone
+			f.id,
+			f.feed_url,
+			f.site_url,
+			f.title,
+			f.etag_header,
+			f.last_modified_header,
+			f.user_id, f.checked_at at time zone u.timezone,
+			f.parsing_error_count,
+			f.parsing_error_msg,
+			f.scraper_rules,
+			f.rewrite_rules,
+			f.crawler,
+			f.user_agent,
+			f.username,
+			f.password,
+			f.disabled,
+			f.category_id,
+			c.title as category_title,
+			fi.icon_id,
+			u.timezone
 		FROM feeds f
 		LEFT JOIN categories c ON c.id=f.category_id
 		LEFT JOIN feed_icons fi ON fi.feed_id=f.id
 		LEFT JOIN users u ON u.id=f.user_id
-		WHERE f.user_id=$1 AND f.id=$2`
+		WHERE
+			f.user_id=$1 AND f.id=$2
+	`
 
 	err := s.db.QueryRow(query, userID, feedID).Scan(
 		&feed.ID,
@@ -246,7 +284,7 @@ func (s *Storage) FeedByID(userID, feedID int64) (*model.Feed, error) {
 	case err == sql.ErrNoRows:
 		return nil, nil
 	case err != nil:
-		return nil, fmt.Errorf("unable to fetch feed #%d: %v", feedID, err)
+		return nil, fmt.Errorf(`store: unable to fetch feed #%d: %v`, feedID, err)
 	}
 
 	if iconID != nil {
@@ -260,14 +298,25 @@ func (s *Storage) FeedByID(userID, feedID int64) (*model.Feed, error) {
 // CreateFeed creates a new feed.
 func (s *Storage) CreateFeed(feed *model.Feed) error {
 	sql := `
-		INSERT INTO feeds
-			(feed_url, site_url, title, category_id, user_id, etag_header,
-			last_modified_header, crawler, user_agent, username, password,
-			disabled)
-		VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)
-		RETURNING id
+		INSERT INTO feeds (
+			feed_url,
+			site_url,
+			title,
+			category_id,
+			user_id,
+			etag_header,
+			last_modified_header,
+			crawler,
+			user_agent,
+			username,
+			password,
+			disabled
+		)
+		VALUES
+			($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)
+		RETURNING
+			id
 	`
-
 	err := s.db.QueryRow(
 		sql,
 		feed.FeedURL,
@@ -284,7 +333,7 @@ func (s *Storage) CreateFeed(feed *model.Feed) error {
 		feed.Disabled,
 	).Scan(&feed.ID)
 	if err != nil {
-		return fmt.Errorf("unable to create feed %q: %v", feed.FeedURL, err)
+		return fmt.Errorf(`store: unable to create feed %q: %v`, feed.FeedURL, err)
 	}
 
 	for i := 0; i < len(feed.Entries); i++ {
@@ -305,7 +354,9 @@ func (s *Storage) CreateFeed(feed *model.Feed) error {
 // UpdateFeed updates an existing feed.
 func (s *Storage) UpdateFeed(feed *model.Feed) (err error) {
 	query := `
-		UPDATE feeds SET
+		UPDATE
+			feeds
+		SET
 			feed_url=$1,
 			site_url=$2,
 			title=$3,
@@ -325,7 +376,6 @@ func (s *Storage) UpdateFeed(feed *model.Feed) (err error) {
 		WHERE
 			id=$17 AND user_id=$18
 	`
-
 	_, err = s.db.Exec(query,
 		feed.FeedURL,
 		feed.SiteURL,
@@ -348,7 +398,7 @@ func (s *Storage) UpdateFeed(feed *model.Feed) (err error) {
 	)
 
 	if err != nil {
-		return fmt.Errorf("unable to update feed #%d (%s): %v", feed.ID, feed.FeedURL, err)
+		return fmt.Errorf(`store: unable to update feed #%d (%s): %v`, feed.ID, feed.FeedURL, err)
 	}
 
 	return nil
@@ -357,13 +407,15 @@ func (s *Storage) UpdateFeed(feed *model.Feed) (err error) {
 // UpdateFeedError updates feed errors.
 func (s *Storage) UpdateFeedError(feed *model.Feed) (err error) {
 	query := `
-		UPDATE feeds
+		UPDATE
+			feeds
 		SET
 			parsing_error_msg=$1,
 			parsing_error_count=$2,
 			checked_at=$3
-		WHERE id=$4 AND user_id=$5`
-
+		WHERE
+			id=$4 AND user_id=$5
+	`
 	_, err = s.db.Exec(query,
 		feed.ParsingErrorMsg,
 		feed.ParsingErrorCount,
@@ -373,7 +425,7 @@ func (s *Storage) UpdateFeedError(feed *model.Feed) (err error) {
 	)
 
 	if err != nil {
-		return fmt.Errorf("unable to update feed error #%d (%s): %v", feed.ID, feed.FeedURL, err)
+		return fmt.Errorf(`store: unable to update feed error #%d (%s): %v`, feed.ID, feed.FeedURL, err)
 	}
 
 	return nil
@@ -381,18 +433,19 @@ func (s *Storage) UpdateFeedError(feed *model.Feed) (err error) {
 
 // RemoveFeed removes a feed.
 func (s *Storage) RemoveFeed(userID, feedID int64) error {
-	result, err := s.db.Exec("DELETE FROM feeds WHERE id = $1 AND user_id = $2", feedID, userID)
+	query := `DELETE FROM feeds WHERE id = $1 AND user_id = $2`
+	result, err := s.db.Exec(query, feedID, userID)
 	if err != nil {
-		return fmt.Errorf("unable to remove feed #%d: %v", feedID, err)
+		return fmt.Errorf(`store: unable to remove feed #%d: %v`, feedID, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to remove feed #%d: %v", feedID, err)
+		return fmt.Errorf(`store: unable to remove feed #%d: %v`, feedID, err)
 	}
 
 	if count == 0 {
-		return errors.New("no feed has been removed")
+		return errors.New(`store: no feed has been removed`)
 	}
 
 	return nil
diff --git a/storage/icon.go b/storage/icon.go
index 7ad7d06..af7f323 100644
--- a/storage/icon.go
+++ b/storage/icon.go
@@ -14,10 +14,10 @@ import (
 
 // HasIcon checks if the given feed has an icon.
 func (s *Storage) HasIcon(feedID int64) bool {
-	var result int
-	query := `SELECT count(*) as c FROM feed_icons WHERE feed_id=$1`
+	var result bool
+	query := `SELECT true FROM feed_icons WHERE feed_id=$1`
 	s.db.QueryRow(query, feedID).Scan(&result)
-	return result == 1
+	return result
 }
 
 // IconByID returns an icon by the ID.
@@ -38,18 +38,21 @@ func (s *Storage) IconByID(iconID int64) (*model.Icon, error) {
 func (s *Storage) IconByFeedID(userID, feedID int64) (*model.Icon, error) {
 	query := `
 		SELECT
-		icons.id, icons.hash, icons.mime_type, icons.content
+			icons.id,
+			icons.hash,
+			icons.mime_type,
+			icons.content
 		FROM icons
 		LEFT JOIN feed_icons ON feed_icons.icon_id=icons.id
 		LEFT JOIN feeds ON feeds.id=feed_icons.feed_id
-		WHERE feeds.user_id=$1 AND feeds.id=$2
+		WHERE
+			feeds.user_id=$1 AND feeds.id=$2
 		LIMIT 1
 	`
-
 	var icon model.Icon
 	err := s.db.QueryRow(query, userID, feedID).Scan(&icon.ID, &icon.Hash, &icon.MimeType, &icon.Content)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch icon: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch icon: %v`, err)
 	}
 
 	return &icon, nil
@@ -61,7 +64,7 @@ func (s *Storage) IconByHash(icon *model.Icon) error {
 	if err == sql.ErrNoRows {
 		return nil
 	} else if err != nil {
-		return fmt.Errorf("Unable to fetch icon by hash: %v", err)
+		return fmt.Errorf(`store: unable to fetch icon by hash: %v`, err)
 	}
 
 	return nil
@@ -71,10 +74,11 @@ func (s *Storage) IconByHash(icon *model.Icon) error {
 func (s *Storage) CreateIcon(icon *model.Icon) error {
 	query := `
 		INSERT INTO icons
-		(hash, mime_type, content)
+			(hash, mime_type, content)
 		VALUES
-		($1, $2, $3)
-		RETURNING id
+			($1, $2, $3)
+		RETURNING
+			id
 	`
 	err := s.db.QueryRow(
 		query,
@@ -84,7 +88,7 @@ func (s *Storage) CreateIcon(icon *model.Icon) error {
 	).Scan(&icon.ID)
 
 	if err != nil {
-		return fmt.Errorf("Unable to create icon: %v", err)
+		return fmt.Errorf(`store: unable to create icon: %v`, err)
 	}
 
 	return nil
@@ -106,7 +110,7 @@ func (s *Storage) CreateFeedIcon(feedID int64, icon *model.Icon) error {
 
 	_, err = s.db.Exec(`INSERT INTO feed_icons (feed_id, icon_id) VALUES ($1, $2)`, feedID, icon.ID)
 	if err != nil {
-		return fmt.Errorf("unable to create feed icon: %v", err)
+		return fmt.Errorf(`store: unable to create feed icon: %v`, err)
 	}
 
 	return nil
@@ -116,16 +120,19 @@ func (s *Storage) CreateFeedIcon(feedID int64, icon *model.Icon) error {
 func (s *Storage) Icons(userID int64) (model.Icons, error) {
 	query := `
 		SELECT
-		icons.id, icons.hash, icons.mime_type, icons.content
+			icons.id,
+			icons.hash,
+			icons.mime_type,
+			icons.content
 		FROM icons
 		LEFT JOIN feed_icons ON feed_icons.icon_id=icons.id
 		LEFT JOIN feeds ON feeds.id=feed_icons.feed_id
-		WHERE feeds.user_id=$1
+		WHERE
+			feeds.user_id=$1
 	`
-
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch icons: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch icons: %v`, err)
 	}
 	defer rows.Close()
 
@@ -134,7 +141,7 @@ func (s *Storage) Icons(userID int64) (model.Icons, error) {
 		var icon model.Icon
 		err := rows.Scan(&icon.ID, &icon.Hash, &icon.MimeType, &icon.Content)
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch icons row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch icons row: %v`, err)
 		}
 		icons = append(icons, &icon)
 	}
diff --git a/storage/integration.go b/storage/integration.go
index 98d15e8..e9653d3 100644
--- a/storage/integration.go
+++ b/storage/integration.go
@@ -13,16 +13,10 @@ import (
 
 // HasDuplicateFeverUsername checks if another user have the same fever username.
 func (s *Storage) HasDuplicateFeverUsername(userID int64, feverUsername string) bool {
-	query := `
-		SELECT
-			count(*) as c
-		FROM integrations
-		WHERE user_id != $1 AND fever_username=$2
-	`
-
-	var result int
+	query := `SELECT true FROM integrations WHERE user_id != $1 AND fever_username=$2`
+	var result bool
 	s.db.QueryRow(query, userID, feverUsername).Scan(&result)
-	return result >= 1
+	return result
 }
 
 // UserByFeverToken returns a user by using the Fever API token.
@@ -32,7 +26,8 @@ func (s *Storage) UserByFeverToken(token string) (*model.User, error) {
 			users.id, users.is_admin, users.timezone
 		FROM users
 		LEFT JOIN integrations ON integrations.user_id=users.id
-		WHERE integrations.fever_enabled='t' AND lower(integrations.fever_token)=lower($1)
+		WHERE
+			integrations.fever_enabled='t' AND lower(integrations.fever_token)=lower($1)
 	`
 
 	var user model.User
@@ -42,14 +37,15 @@ func (s *Storage) UserByFeverToken(token string) (*model.User, error) {
 		return nil, nil
 	case err != nil:
 		return nil, fmt.Errorf("unable to fetch user: %v", err)
+	default:
+		return &user, nil
 	}
-
-	return &user, nil
 }
 
 // Integration returns user integration settings.
 func (s *Storage) Integration(userID int64) (*model.Integration, error) {
-	query := `SELECT
+	query := `
+		SELECT
 			user_id,
 			pinboard_enabled,
 			pinboard_token,
@@ -74,8 +70,10 @@ func (s *Storage) Integration(userID int64) (*model.Integration, error) {
 			pocket_enabled,
 			pocket_access_token,
 			pocket_consumer_key
-		FROM integrations
-		WHERE user_id=$1
+		FROM
+			integrations
+		WHERE
+			user_id=$1
 	`
 	var integration model.Integration
 	err := s.db.QueryRow(query, userID).Scan(
@@ -108,16 +106,18 @@ func (s *Storage) Integration(userID int64) (*model.Integration, error) {
 	case err == sql.ErrNoRows:
 		return &integration, nil
 	case err != nil:
-		return &integration, fmt.Errorf("unable to fetch integration row: %v", err)
+		return &integration, fmt.Errorf(`store: unable to fetch integration row: %v`, err)
+	default:
+		return &integration, nil
 	}
-
-	return &integration, nil
 }
 
 // UpdateIntegration saves user integration settings.
 func (s *Storage) UpdateIntegration(integration *model.Integration) error {
 	query := `
-		UPDATE integrations SET
+		UPDATE
+			integrations
+		SET
 			pinboard_enabled=$1,
 			pinboard_token=$2,
 			pinboard_tags=$3,
@@ -141,7 +141,8 @@ func (s *Storage) UpdateIntegration(integration *model.Integration) error {
 			pocket_enabled=$21,
 			pocket_access_token=$22,
 			pocket_consumer_key=$23
-		WHERE user_id=$24
+		WHERE
+			user_id=$24
 	`
 	_, err := s.db.Exec(
 		query,
@@ -172,7 +173,7 @@ func (s *Storage) UpdateIntegration(integration *model.Integration) error {
 	)
 
 	if err != nil {
-		return fmt.Errorf("unable to update integration row: %v", err)
+		return fmt.Errorf(`store: unable to update integration row: %v`, err)
 	}
 
 	return nil
@@ -183,7 +184,7 @@ func (s *Storage) CreateIntegration(userID int64) error {
 	query := `INSERT INTO integrations (user_id) VALUES ($1)`
 	_, err := s.db.Exec(query, userID)
 	if err != nil {
-		return fmt.Errorf("unable to create integration row: %v", err)
+		return fmt.Errorf(`store: unable to create integration row: %v`, err)
 	}
 
 	return nil
@@ -192,11 +193,15 @@ func (s *Storage) CreateIntegration(userID int64) error {
 // HasSaveEntry returns true if the given user can save articles to third-parties.
 func (s *Storage) HasSaveEntry(userID int64) (result bool) {
 	query := `
-		SELECT true FROM integrations
-		WHERE user_id=$1 AND
-		(pinboard_enabled='t' OR instapaper_enabled='t' OR wallabag_enabled='t' OR nunux_keeper_enabled='t' OR pocket_enabled='t')
+		SELECT
+			true
+		FROM
+			integrations
+		WHERE
+			user_id=$1
+		AND
+			(pinboard_enabled='t' OR instapaper_enabled='t' OR wallabag_enabled='t' OR nunux_keeper_enabled='t' OR pocket_enabled='t')
 	`
-
 	if err := s.db.QueryRow(query, userID).Scan(&result); err != nil {
 		result = false
 	}
diff --git a/storage/job.go b/storage/job.go
index c231c97..3d795dd 100644
--- a/storage/job.go
+++ b/storage/job.go
@@ -16,12 +16,14 @@ const maxParsingError = 3
 func (s *Storage) NewBatch(batchSize int) (jobs model.JobList, err error) {
 	query := `
 		SELECT
-		id, user_id
-		FROM feeds
-		WHERE parsing_error_count < $1 AND disabled is false
+			id,
+			user_id
+		FROM
+			feeds
+		WHERE
+			parsing_error_count < $1 AND disabled is false
 		ORDER BY checked_at ASC LIMIT %d
 	`
-
 	return s.fetchBatchRows(fmt.Sprintf(query, batchSize), maxParsingError)
 }
 
@@ -31,26 +33,28 @@ func (s *Storage) NewUserBatch(userID int64, batchSize int) (jobs model.JobList,
 	// user refresh manually all his feeds to force a refresh.
 	query := `
 		SELECT
-		id, user_id
-		FROM feeds
-		WHERE user_id=$1 AND disabled is false
+			id,
+			user_id
+		FROM
+			feeds
+		WHERE
+			user_id=$1 AND disabled is false
 		ORDER BY checked_at ASC LIMIT %d
 	`
-
 	return s.fetchBatchRows(fmt.Sprintf(query, batchSize), userID)
 }
 
 func (s *Storage) fetchBatchRows(query string, args ...interface{}) (jobs model.JobList, err error) {
 	rows, err := s.db.Query(query, args...)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch batch of jobs: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch batch of jobs: %v`, err)
 	}
 	defer rows.Close()
 
 	for rows.Next() {
 		var job model.Job
 		if err := rows.Scan(&job.FeedID, &job.UserID); err != nil {
-			return nil, fmt.Errorf("unable to fetch job: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch job: %v`, err)
 		}
 
 		jobs = append(jobs, job)
diff --git a/storage/session.go b/storage/session.go
index f57d2eb..f57b68e 100644
--- a/storage/session.go
+++ b/storage/session.go
@@ -44,9 +44,10 @@ func (s *Storage) CreateAppSession() (*model.Session, error) {
 }
 
 func (s *Storage) createAppSession(session *model.Session) (*model.Session, error) {
-	_, err := s.db.Exec(`INSERT INTO sessions (id, data) VALUES ($1, $2)`, session.ID, session.Data)
+	query := `INSERT INTO sessions (id, data) VALUES ($1, $2)`
+	_, err := s.db.Exec(query, session.ID, session.Data)
 	if err != nil {
-		return nil, fmt.Errorf("unable to create app session: %v", err)
+		return nil, fmt.Errorf(`store: unable to create app session: %v`, err)
 	}
 
 	return session, nil
@@ -54,13 +55,17 @@ func (s *Storage) createAppSession(session *model.Session) (*model.Session, erro
 
 // UpdateAppSessionField updates only one session field.
 func (s *Storage) UpdateAppSessionField(sessionID, field string, value interface{}) error {
-	query := `UPDATE sessions
-		SET data = jsonb_set(data, '{%s}', to_jsonb($1::text), true)
-		WHERE id=$2`
-
+	query := `
+		UPDATE
+			sessions
+		SET
+			data = jsonb_set(data, '{%s}', to_jsonb($1::text), true)
+		WHERE
+			id=$2
+	`
 	_, err := s.db.Exec(fmt.Sprintf(query, field), value, sessionID)
 	if err != nil {
-		return fmt.Errorf("unable to update session field: %v", err)
+		return fmt.Errorf(`store: unable to update session field: %v`, err)
 	}
 
 	return nil
@@ -76,13 +81,14 @@ func (s *Storage) AppSession(id string) (*model.Session, error) {
 		&session.Data,
 	)
 
-	if err == sql.ErrNoRows {
-		return nil, fmt.Errorf("session not found: %s", id)
-	} else if err != nil {
-		return nil, fmt.Errorf("unable to fetch session: %v", err)
+	switch {
+	case err == sql.ErrNoRows:
+		return nil, fmt.Errorf(`store: session not found: %s`, id)
+	case err != nil:
+		return nil, fmt.Errorf(`store: unable to fetch session: %v`, err)
+	default:
+		return &session, nil
 	}
-
-	return &session, nil
 }
 
 // FlushAllSessions removes all sessions from the database.
@@ -102,10 +108,13 @@ func (s *Storage) FlushAllSessions() (err error) {
 
 // CleanOldSessions removes sessions older than specified days.
 func (s *Storage) CleanOldSessions(days int) int64 {
-	query := fmt.Sprintf(`DELETE FROM sessions
-		WHERE id IN (SELECT id FROM sessions WHERE created_at < now() - interval '%d days')`, days)
-
-	result, err := s.db.Exec(query)
+	query := `
+		DELETE FROM
+			sessions
+		WHERE
+			id IN (SELECT id FROM sessions WHERE created_at < now() - interval '%d days')
+	`
+	result, err := s.db.Exec(fmt.Sprintf(query, days))
 	if err != nil {
 		return 0
 	}
diff --git a/storage/timezone.go b/storage/timezone.go
index e5174ca..d21ac26 100644
--- a/storage/timezone.go
+++ b/storage/timezone.go
@@ -14,14 +14,14 @@ func (s *Storage) Timezones() (map[string]string, error) {
 	timezones := make(map[string]string)
 	rows, err := s.db.Query(`SELECT name FROM pg_timezone_names() ORDER BY name ASC`)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch timezones: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch timezones: %v`, err)
 	}
 	defer rows.Close()
 
 	for rows.Next() {
 		var timezone string
 		if err := rows.Scan(&timezone); err != nil {
-			return nil, fmt.Errorf("unable to fetch timezones row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch timezones row: %v`, err)
 		}
 
 		if !strings.HasPrefix(timezone, "posix") && !strings.HasPrefix(timezone, "SystemV") && timezone != "localtime" {
diff --git a/storage/user.go b/storage/user.go
index cd85f8d..39b50ef 100644
--- a/storage/user.go
+++ b/storage/user.go
@@ -18,10 +18,10 @@ import (
 
 // SetLastLogin updates the last login date of a user.
 func (s *Storage) SetLastLogin(userID int64) error {
-	query := "UPDATE users SET last_login_at=now() WHERE id=$1"
+	query := `UPDATE users SET last_login_at=now() WHERE id=$1`
 	_, err := s.db.Exec(query, userID)
 	if err != nil {
-		return fmt.Errorf("unable to update last login date: %v", err)
+		return fmt.Errorf(`store: unable to update last login date: %v`, err)
 	}
 
 	return nil
@@ -29,16 +29,16 @@ func (s *Storage) SetLastLogin(userID int64) error {
 
 // UserExists checks if a user exists by using the given username.
 func (s *Storage) UserExists(username string) bool {
-	var result int
-	s.db.QueryRow(`SELECT count(*) as c FROM users WHERE username=LOWER($1)`, username).Scan(&result)
-	return result >= 1
+	var result bool
+	s.db.QueryRow(`SELECT true FROM users WHERE username=LOWER($1)`, username).Scan(&result)
+	return result
 }
 
 // AnotherUserExists checks if another user exists with the given username.
 func (s *Storage) AnotherUserExists(userID int64, username string) bool {
-	var result int
-	s.db.QueryRow(`SELECT count(*) as c FROM users WHERE id != $1 AND username=LOWER($2)`, userID, username).Scan(&result)
-	return result >= 1
+	var result bool
+	s.db.QueryRow(`SELECT true FROM users WHERE id != $1 AND username=LOWER($2)`, userID, username).Scan(&result)
+	return result
 }
 
 // CreateUser creates a new user.
@@ -79,7 +79,7 @@ func (s *Storage) CreateUser(user *model.User) (err error) {
 		&user.KeyboardShortcuts,
 	)
 	if err != nil {
-		return fmt.Errorf("unable to create user: %v", err)
+		return fmt.Errorf(`store: unable to create user: %v`, err)
 	}
 
 	s.CreateCategory(&model.Category{Title: "All", UserID: user.ID})
@@ -92,7 +92,7 @@ func (s *Storage) UpdateExtraField(userID int64, field, value string) error {
 	query := fmt.Sprintf(`UPDATE users SET extra = hstore('%s', $1) WHERE id=$2`, field)
 	_, err := s.db.Exec(query, value, userID)
 	if err != nil {
-		return fmt.Errorf("unable to update user extra field: %v", err)
+		return fmt.Errorf(`store: unable to update user extra field: %v`, err)
 	}
 	return nil
 }
@@ -102,7 +102,7 @@ func (s *Storage) RemoveExtraField(userID int64, field string) error {
 	query := `UPDATE users SET extra = delete(extra, $1) WHERE id=$2`
 	_, err := s.db.Exec(query, field, userID)
 	if err != nil {
-		return fmt.Errorf("unable to remove user extra field: %v", err)
+		return fmt.Errorf(`store: unable to remove user extra field: %v`, err)
 	}
 	return nil
 }
@@ -142,7 +142,7 @@ func (s *Storage) UpdateUser(user *model.User) error {
 			user.ID,
 		)
 		if err != nil {
-			return fmt.Errorf("unable to update user: %v", err)
+			return fmt.Errorf(`store: unable to update user: %v`, err)
 		}
 	} else {
 		query := `
@@ -171,7 +171,7 @@ func (s *Storage) UpdateUser(user *model.User) error {
 		)
 
 		if err != nil {
-			return fmt.Errorf("unable to update user: %v", err)
+			return fmt.Errorf(`store: unable to update user: %v`, err)
 		}
 	}
 
@@ -192,14 +192,21 @@ func (s *Storage) UserLanguage(userID int64) (language string) {
 func (s *Storage) UserByID(userID int64) (*model.User, error) {
 	query := `
 		SELECT
-			id, username, is_admin, theme, language, timezone, entry_direction, keyboard_shortcuts,
-			last_login_at, extra
+			id,
+			username,
+			is_admin,
+			theme,
+			language,
+			timezone,
+			entry_direction,
+			keyboard_shortcuts,
+			last_login_at,
+			extra
 		FROM
 			users
 		WHERE
 			id = $1
 	`
-
 	return s.fetchUser(query, userID)
 }
 
@@ -207,14 +214,21 @@ func (s *Storage) UserByID(userID int64) (*model.User, error) {
 func (s *Storage) UserByUsername(username string) (*model.User, error) {
 	query := `
 		SELECT
-			id, username, is_admin, theme, language, timezone, entry_direction, keyboard_shortcuts,
-			last_login_at, extra
+			id,
+			username,
+			is_admin,
+			theme,
+			language,
+			timezone,
+			entry_direction,
+			keyboard_shortcuts,
+			last_login_at,
+			extra
 		FROM
 			users
 		WHERE
 			username=LOWER($1)
 	`
-
 	return s.fetchUser(query, username)
 }
 
@@ -222,14 +236,21 @@ func (s *Storage) UserByUsername(username string) (*model.User, error) {
 func (s *Storage) UserByExtraField(field, value string) (*model.User, error) {
 	query := `
 		SELECT
-			id, username, is_admin, theme, language, timezone, entry_direction, keyboard_shortcuts,
-			last_login_at, extra
+			id,
+			username,
+			is_admin,
+			theme,
+			language,
+			timezone,
+			entry_direction,
+			keyboard_shortcuts,
+			last_login_at,
+			extra
 		FROM
 			users
 		WHERE
 			extra->$1=$2
 	`
-
 	return s.fetchUser(query, field, value)
 }
 
@@ -253,7 +274,7 @@ func (s *Storage) fetchUser(query string, args ...interface{}) (*model.User, err
 	if err == sql.ErrNoRows {
 		return nil, nil
 	} else if err != nil {
-		return nil, fmt.Errorf("unable to fetch user: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch user: %v`, err)
 	}
 
 	for key, value := range extra.Map {
@@ -269,16 +290,16 @@ func (s *Storage) fetchUser(query string, args ...interface{}) (*model.User, err
 func (s *Storage) RemoveUser(userID int64) error {
 	result, err := s.db.Exec("DELETE FROM users WHERE id = $1", userID)
 	if err != nil {
-		return fmt.Errorf("unable to remove this user: %v", err)
+		return fmt.Errorf(`store: unable to remove this user: %v`, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to remove this user: %v", err)
+		return fmt.Errorf(`store: unable to remove this user: %v`, err)
 	}
 
 	if count == 0 {
-		return errors.New("nothing has been removed")
+		return errors.New(`store: nothing has been removed`)
 	}
 
 	return nil
@@ -288,16 +309,23 @@ func (s *Storage) RemoveUser(userID int64) error {
 func (s *Storage) Users() (model.Users, error) {
 	query := `
 		SELECT
-			id, username, is_admin, theme, language, timezone, entry_direction, keyboard_shortcuts,
-			last_login_at, extra
+			id,
+			username,
+			is_admin,
+			theme,
+			language,
+			timezone,
+			entry_direction,
+			keyboard_shortcuts,
+			last_login_at,
+			extra
 		FROM
 			users
 		ORDER BY username ASC
 	`
-
 	rows, err := s.db.Query(query)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch users: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch users: %v`, err)
 	}
 	defer rows.Close()
 
@@ -319,7 +347,7 @@ func (s *Storage) Users() (model.Users, error) {
 		)
 
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch users row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch users row: %v`, err)
 		}
 
 		for key, value := range extra.Map {
@@ -341,13 +369,13 @@ func (s *Storage) CheckPassword(username, password string) error {
 
 	err := s.db.QueryRow("SELECT password FROM users WHERE username=$1", username).Scan(&hash)
 	if err == sql.ErrNoRows {
-		return fmt.Errorf("unable to find this user: %s", username)
+		return fmt.Errorf(`store: unable to find this user: %s`, username)
 	} else if err != nil {
-		return fmt.Errorf("unable to fetch user: %v", err)
+		return fmt.Errorf(`store: unable to fetch user: %v`, err)
 	}
 
 	if err := bcrypt.CompareHashAndPassword([]byte(hash), []byte(password)); err != nil {
-		return fmt.Errorf(`invalid password for "%s" (%v)`, username, err)
+		return fmt.Errorf(`store: invalid password for "%s" (%v)`, username, err)
 	}
 
 	return nil
@@ -362,7 +390,7 @@ func (s *Storage) HasPassword(userID int64) (bool, error) {
 	if err == sql.ErrNoRows {
 		return false, nil
 	} else if err != nil {
-		return false, fmt.Errorf("unable to execute query: %v", err)
+		return false, fmt.Errorf(`store: unable to execute query: %v`, err)
 	}
 
 	if result {
diff --git a/storage/user_session.go b/storage/user_session.go
index 5fa0f0a..603a875 100644
--- a/storage/user_session.go
+++ b/storage/user_session.go
@@ -14,13 +14,22 @@ import (
 
 // UserSessions returns the list of sessions for the given user.
 func (s *Storage) UserSessions(userID int64) (model.UserSessions, error) {
-	query := `SELECT
-		id, user_id, token, created_at, user_agent, ip
-		FROM user_sessions
-		WHERE user_id=$1 ORDER BY id DESC`
+	query := `
+		SELECT
+			id,
+			user_id,
+			token,
+			created_at,
+			user_agent,
+			ip
+		FROM
+			user_sessions
+		WHERE
+			user_id=$1 ORDER BY id DESC
+	`
 	rows, err := s.db.Query(query, userID)
 	if err != nil {
-		return nil, fmt.Errorf("unable to fetch user sessions: %v", err)
+		return nil, fmt.Errorf(`store: unable to fetch user sessions: %v`, err)
 	}
 	defer rows.Close()
 
@@ -37,7 +46,7 @@ func (s *Storage) UserSessions(userID int64) (model.UserSessions, error) {
 		)
 
 		if err != nil {
-			return nil, fmt.Errorf("unable to fetch user session row: %v", err)
+			return nil, fmt.Errorf(`store: unable to fetch user session row: %v`, err)
 		}
 
 		sessions = append(sessions, &session)
@@ -48,16 +57,17 @@ func (s *Storage) UserSessions(userID int64) (model.UserSessions, error) {
 
 // CreateUserSession creates a new sessions.
 func (s *Storage) CreateUserSession(username, userAgent, ip string) (sessionID string, userID int64, err error) {
-	err = s.db.QueryRow("SELECT id FROM users WHERE username = LOWER($1)", username).Scan(&userID)
+	query := `SELECT id FROM users WHERE username = LOWER($1)`
+	err = s.db.QueryRow(query, username).Scan(&userID)
 	if err != nil {
-		return "", 0, fmt.Errorf("unable to fetch user ID: %v", err)
+		return "", 0, fmt.Errorf(`store: unable to fetch user ID: %v`, err)
 	}
 
 	token := crypto.GenerateRandomString(64)
-	query := "INSERT INTO user_sessions (token, user_id, user_agent, ip) VALUES ($1, $2, $3, $4)"
+	query = `INSERT INTO user_sessions (token, user_id, user_agent, ip) VALUES ($1, $2, $3, $4)`
 	_, err = s.db.Exec(query, token, userID, userAgent, ip)
 	if err != nil {
-		return "", 0, fmt.Errorf("unable to create user session: %v", err)
+		return "", 0, fmt.Errorf(`store: unable to create user session: %v`, err)
 	}
 
 	return token, userID, nil
@@ -67,7 +77,19 @@ func (s *Storage) CreateUserSession(username, userAgent, ip string) (sessionID s
 func (s *Storage) UserSessionByToken(token string) (*model.UserSession, error) {
 	var session model.UserSession
 
-	query := "SELECT id, user_id, token, created_at, user_agent, ip FROM user_sessions WHERE token = $1"
+	query := `
+		SELECT
+			id,
+			user_id,
+			token,
+			created_at,
+			user_agent,
+			ip 
+		FROM
+			user_sessions
+		WHERE
+			token = $1
+	`
 	err := s.db.QueryRow(query, token).Scan(
 		&session.ID,
 		&session.UserID,
@@ -77,29 +99,31 @@ func (s *Storage) UserSessionByToken(token string) (*model.UserSession, error) {
 		&session.IP,
 	)
 
-	if err == sql.ErrNoRows {
+	switch {
+	case err == sql.ErrNoRows:
 		return nil, nil
-	} else if err != nil {
-		return nil, fmt.Errorf("unable to fetch user session: %v", err)
+	case err != nil:
+		return nil, fmt.Errorf(`store: unable to fetch user session: %v`, err)
+	default:
+		return &session, nil
 	}
-
-	return &session, nil
 }
 
 // RemoveUserSessionByToken remove a session by using the token.
 func (s *Storage) RemoveUserSessionByToken(userID int64, token string) error {
-	result, err := s.db.Exec(`DELETE FROM user_sessions WHERE user_id=$1 AND token=$2`, userID, token)
+	query := `DELETE FROM user_sessions WHERE user_id=$1 AND token=$2`
+	result, err := s.db.Exec(query, userID, token)
 	if err != nil {
-		return fmt.Errorf("unable to remove this user session: %v", err)
+		return fmt.Errorf(`store: unable to remove this user session: %v`, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to remove this user session: %v", err)
+		return fmt.Errorf(`store: unable to remove this user session: %v`, err)
 	}
 
 	if count != 1 {
-		return fmt.Errorf("nothing has been removed")
+		return fmt.Errorf(`store: nothing has been removed`)
 	}
 
 	return nil
@@ -107,18 +131,19 @@ func (s *Storage) RemoveUserSessionByToken(userID int64, token string) error {
 
 // RemoveUserSessionByID remove a session by using the ID.
 func (s *Storage) RemoveUserSessionByID(userID, sessionID int64) error {
-	result, err := s.db.Exec(`DELETE FROM user_sessions WHERE user_id=$1 AND id=$2`, userID, sessionID)
+	query := `DELETE FROM user_sessions WHERE user_id=$1 AND id=$2`
+	result, err := s.db.Exec(query, userID, sessionID)
 	if err != nil {
-		return fmt.Errorf("unable to remove this user session: %v", err)
+		return fmt.Errorf(`store: unable to remove this user session: %v`, err)
 	}
 
 	count, err := result.RowsAffected()
 	if err != nil {
-		return fmt.Errorf("unable to remove this user session: %v", err)
+		return fmt.Errorf(`store: unable to remove this user session: %v`, err)
 	}
 
 	if count != 1 {
-		return fmt.Errorf("nothing has been removed")
+		return fmt.Errorf(`store: nothing has been removed`)
 	}
 
 	return nil
@@ -126,10 +151,13 @@ func (s *Storage) RemoveUserSessionByID(userID, sessionID int64) error {
 
 // CleanOldUserSessions removes user sessions older than specified days.
 func (s *Storage) CleanOldUserSessions(days int) int64 {
-	query := fmt.Sprintf(`DELETE FROM user_sessions
-		WHERE id IN (SELECT id FROM user_sessions WHERE created_at < now() - interval '%d days')`, days)
-
-	result, err := s.db.Exec(query)
+	query := `
+		DELETE FROM
+			user_sessions
+		WHERE
+			id IN (SELECT id FROM user_sessions WHERE created_at < now() - interval '%d days')
+	`
+	result, err := s.db.Exec(fmt.Sprintf(query, days))
 	if err != nil {
 		return 0
 	}