refactor(backend): switch to DDD

backend/internal/domain/entity.go

@@ -52,7 +52,6 @@ type (
 		Creator   User            `json:"creator"`
 		Notes     pgtype.Text     `json:"notes"`
 		Metadata  json.RawMessage `json:"metadata"`
-		Tags      []TagCore       `json:"tags"`
 		Viewed    int             `json:"viewed"`
 	}
 )

backend/internal/domain/errors.go

@@ -0,0 +1,46 @@
+package domain
+
+type ErrorCode string
+
+const (
+	// File errors
+	ErrFileNotFound     ErrorCode = "FILE_NOT_FOUND"
+	ErrMIMENotSupported ErrorCode = "MIME_NOT_SUPPORTEDF"
+
+	// Tag errors
+	ErrTagNotFound ErrorCode = "TAG_NOT_FOUND"
+
+	// General errors
+	ErrValidation ErrorCode = "VALIDATION_ERROR"
+	ErrInternal   ErrorCode = "INTERNAL_SERVER_ERROR"
+)
+
+type DomainError struct {
+	Err     error     `json:"-"`
+	Code    ErrorCode `json:"code"`
+	Message string    `json:"message"`
+	Details []any     `json:"-"`
+}
+
+func (e *DomainError) Error() string {
+	if e.Err != nil {
+		return e.Message + ": " + e.Err.Error()
+	}
+	return e.Message
+}
+
+func NewDomainError(err error, code ErrorCode, details ...any) *DomainError {
+	return &DomainError{
+		Err:     err,
+		Code:    code,
+		Details: details,
+	}
+}
+
+func NewUnexpectedError(err error) *DomainError {
+	return &DomainError{
+		Err:     err,
+		Code:    ErrInternal,
+		Message: "An unexpected error occured",
+	}
+}

backend/internal/domain/repositories.go

@@ -0,0 +1,16 @@
+package domain
+
+import (
+	"context"
+	"encoding/json"
+	"time"
+)
+
+type FileRepository interface {
+	GetAccess(ctx context.Context, user_id int, file_id string) (canView, canEdit bool, domainErr *DomainError)
+	GetSlice(ctx context.Context, user_id int, filter, sort string, limit, offset int) (files Slice[FileItem], domainErr *DomainError)
+	Get(ctx context.Context, user_id int, file_id string) (file FileFull, domainErr *DomainError)
+	Add(ctx context.Context, user_id int, name, mime string, datetime time.Time, notes string, metadata json.RawMessage) (file FileCore, domainErr *DomainError)
+	Update(ctx context.Context, user_id int, file_id string, updates map[string]interface{}) (domainErr *DomainError)
+	Delete(ctx context.Context, user_id int, file_id string) (domainErr *DomainError)
+}

backend/internal/infrastructure/persistence/postgres/db.go

@@ -0,0 +1,50 @@
+package postgres
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"tanabata/internal/domain"
+)
+
+// Initialize PostgreSQL database driver
+func New(dbURL string) (*pgxpool.Pool, error) {
+	poolConfig, err := pgxpool.ParseConfig(dbURL)
+	if err != nil {
+		return nil, fmt.Errorf("error while parsing connection string: %w", err)
+	}
+
+	poolConfig.MaxConns = 100
+	poolConfig.MinConns = 0
+	poolConfig.MaxConnLifetime = time.Hour
+	poolConfig.HealthCheckPeriod = 30 * time.Second
+
+	db, err := pgxpool.NewWithConfig(context.Background(), poolConfig)
+	if err != nil {
+		return nil, fmt.Errorf("error while initializing DB connections pool: %w", err)
+	}
+	return db, nil
+}
+
+// Transaction wrapper
+func transaction(ctx context.Context, db *pgxpool.Pool, handler func(context.Context, pgx.Tx) *domain.DomainError) (domainErr *domain.DomainError) {
+	tx, err := db.Begin(ctx)
+	if err != nil {
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	domainErr = handler(ctx, tx)
+	if domainErr != nil {
+		tx.Rollback(ctx)
+		return
+	}
+	err = tx.Commit(ctx)
+	if err != nil {
+		domainErr = domain.NewUnexpectedError(err)
+	}
+	return
+}

backend/internal/infrastructure/persistence/postgres/file_repository.go

@@ -0,0 +1,272 @@
+package postgres
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgconn"
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"tanabata/internal/domain"
+)
+
+type FileRepository struct {
+	db *pgxpool.Pool
+}
+
+func NewFileRepository(db *pgxpool.Pool) *FileRepository {
+	return &FileRepository{db: db}
+}
+
+// Check if user can view file
+func (s *FileRepository) GetAccess(ctx context.Context, user_id int, file_id string) (canView, canEdit bool, domainErr *domain.DomainError) {
+	row := s.db.QueryRow(ctx, `
+		SELECT 
+			COALESCE(a.view, FALSE) OR f.creator_id=$1 OR COALESCE(u.is_admin, FALSE),
+			COALESCE(a.edit, FALSE) OR f.creator_id=$1 OR COALESCE(u.is_admin, FALSE)
+		FROM data.files f
+		LEFT JOIN acl.files a ON a.file_id=f.id AND a.user_id=$1
+		LEFT JOIN system.users u ON u.id=$1
+		WHERE f.id=$2
+		`, user_id, file_id)
+	err := row.Scan(&canView, &canEdit)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			domainErr = domain.NewDomainError(err, domain.ErrFileNotFound, file_id)
+			return
+		}
+		var pgErr *pgconn.PgError
+		if errors.As(err, &pgErr) && (pgErr.Code == "22P02" || pgErr.Code == "22007") {
+			domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+	}
+	return
+}
+
+// Get a set of files
+func (s *FileRepository) GetSlice(ctx context.Context, user_id int, filter, sort string, limit, offset int) (files domain.Slice[domain.FileItem], domainErr *domain.DomainError) {
+	filterCond, err := filterToSQL(filter)
+	if err != nil {
+		domainErr = domain.NewDomainError(err, domain.ErrValidation, "filter", err.Error())
+		return
+	}
+	sortExpr, err := sortToSQL(sort)
+	if err != nil {
+		domainErr = domain.NewDomainError(err, domain.ErrValidation, "sort param", err.Error())
+		return
+	}
+	// prepare query
+	query := `
+	SELECT
+		f.id,
+		f.name,
+		m.name,
+		m.extension,
+		uuid_extract_timestamp(f.id),
+		u.name,
+		u.is_admin
+	FROM data.files f
+	JOIN system.mime m ON m.id=f.mime_id
+	JOIN system.users u ON u.id=f.creator_id
+	WHERE NOT f.is_deleted AND (f.creator_id=$1 OR (SELECT view FROM acl.files WHERE file_id=f.id AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1)) AND
+	`
+	query += filterCond
+	queryCount := query
+	query += sortExpr
+	if limit >= 0 {
+		query += fmt.Sprintf(" LIMIT %d", limit)
+	}
+	if offset > 0 {
+		query += fmt.Sprintf(" OFFSET %d", offset)
+	}
+	// execute query
+	domainErr = transaction(ctx, s.db, func(ctx context.Context, tx pgx.Tx) (domainErr *domain.DomainError) {
+		rows, err := tx.Query(ctx, query, user_id)
+		if err != nil && !errors.Is(err, pgx.ErrNoRows) {
+			var pgErr *pgconn.PgError
+			if errors.As(err, &pgErr) {
+				switch pgErr.Code {
+				case "22P02", "22007":
+					domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+					return
+				case "42P10":
+					domainErr = domain.NewDomainError(err, domain.ErrValidation, "sort field", sort[1:])
+					return
+				}
+			}
+			domainErr = domain.NewUnexpectedError(err)
+			return
+		}
+		defer rows.Close()
+		count := 0
+		for rows.Next() {
+			var file domain.FileItem
+			err = rows.Scan(&file.ID, &file.Name, &file.MIME.Name, &file.MIME.Extension, &file.CreatedAt, &file.Creator.Name, &file.Creator.IsAdmin)
+			if err != nil {
+				domainErr = domain.NewUnexpectedError(err)
+				return
+			}
+			files.Data = append(files.Data, file)
+			count++
+		}
+		err = rows.Err()
+		if err != nil {
+			domainErr = domain.NewUnexpectedError(err)
+			return
+		}
+		files.Pagination.Limit = limit
+		files.Pagination.Offset = offset
+		files.Pagination.Count = count
+		row := tx.QueryRow(ctx, fmt.Sprintf("SELECT COUNT(*) FROM (%s) tmp", queryCount), user_id)
+		err = row.Scan(&files.Pagination.Total)
+		if err != nil {
+			domainErr = domain.NewUnexpectedError(err)
+		}
+		return
+	})
+	return
+}
+
+// Get file
+func (s *FileRepository) Get(ctx context.Context, user_id int, file_id string) (file domain.FileFull, domainErr *domain.DomainError) {
+	row := s.db.QueryRow(ctx, `
+		SELECT
+			f.id,
+			f.name,
+			m.name,
+			m.extension,
+			uuid_extract_timestamp(f.id),
+			u.name,
+			u.is_admin,
+			f.notes,
+			f.metadata,
+			(SELECT COUNT(*) FROM activity.file_views fv WHERE fv.file_id=$2 AND fv.user_id=$1)
+		FROM data.files f
+		JOIN system.mime m ON m.id=f.mime_id
+		JOIN system.users u ON u.id=f.creator_id
+		WHERE NOT f.is_deleted AND f.id=$2 AND (f.creator_id=$1 OR (SELECT view FROM acl.files WHERE file_id=$2 AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))
+		`, user_id, file_id)
+	err := row.Scan(&file.ID, &file.Name, &file.MIME.Name, &file.MIME.Extension, &file.CreatedAt, &file.Creator.Name, &file.Creator.IsAdmin, &file.Notes, &file.Metadata, &file.Viewed)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			domainErr = domain.NewDomainError(err, domain.ErrFileNotFound, file_id)
+			return
+		}
+		var pgErr *pgconn.PgError
+		if errors.As(err, &pgErr) && (pgErr.Code == "22P02" || pgErr.Code == "22007") {
+			domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	return
+}
+
+// Add file
+func (s *FileRepository) Add(ctx context.Context, user_id int, name, mime string, datetime time.Time, notes string, metadata json.RawMessage) (file domain.FileCore, domainErr *domain.DomainError) {
+	var mime_id int
+	var extension string
+	row := s.db.QueryRow(ctx, "SELECT id, extension FROM system.mime WHERE name=$1", mime)
+	err := row.Scan(&mime_id, &extension)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			domainErr = domain.NewDomainError(err, domain.ErrMIMENotSupported, mime)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	row = s.db.QueryRow(ctx, `
+	INSERT INTO data.files (name, mime_id, datetime, creator_id, notes, metadata)
+	VALUES (NULLIF($1, ''), $2, $3, $4, NULLIF($5 ,''), $6)
+	RETURNING id
+	`, name, mime_id, datetime, user_id, notes, metadata)
+	err = row.Scan(&file.ID)
+	if err != nil {
+		var pgErr *pgconn.PgError
+		if errors.As(err, &pgErr) && (pgErr.Code == "22P02" || pgErr.Code == "22007") {
+			domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	file.Name.String = name
+	file.Name.Valid = (name != "")
+	file.MIME.Name = mime
+	file.MIME.Extension = extension
+	return
+}
+
+// Update file
+func (s *FileRepository) Update(ctx context.Context, user_id int, file_id string, updates map[string]interface{}) (domainErr *domain.DomainError) {
+	if len(updates) == 0 {
+		domainErr = domain.NewDomainError(errors.ErrUnsupported, domain.ErrValidation, "request body", "no fields provided for update")
+		return
+	}
+	writableFields := map[string]bool{
+		"name":     true,
+		"datetime": true,
+		"notes":    true,
+		"metadata": true,
+	}
+	query := "UPDATE data.files SET"
+	newValues := []interface{}{user_id}
+	count := 2
+	for field, value := range updates {
+		if !writableFields[field] {
+			domainErr = domain.NewDomainError(errors.ErrUnsupported, domain.ErrValidation, "field", field)
+			return
+		}
+		query += fmt.Sprintf(" %s=NULLIF($%d, '')", field, count)
+		newValues = append(newValues, value)
+		count++
+	}
+	query += fmt.Sprintf(
+		" WHERE id=$%d AND (creator_id=$1 OR (SELECT edit FROM acl.files WHERE file_id=$%d AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))",
+		count, count)
+	newValues = append(newValues, file_id)
+	commandTag, err := s.db.Exec(ctx, query, newValues...)
+	if err != nil {
+		var pgErr *pgconn.PgError
+		if errors.As(err, &pgErr) && (pgErr.Code == "22P02" || pgErr.Code == "22007") {
+			domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	if commandTag.RowsAffected() == 0 {
+		domainErr = domain.NewDomainError(err, domain.ErrFileNotFound, file_id)
+		return
+	}
+	return
+}
+
+// Delete file
+func (s *FileRepository) Delete(ctx context.Context, user_id int, file_id string) (domainErr *domain.DomainError) {
+	commandTag, err := s.db.Exec(ctx,
+		"DELETE FROM data.files WHERE id=$2 AND (creator_id=$1 OR (SELECT edit FROM acl.files WHERE file_id=$2 AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))",
+		user_id, file_id)
+	if err != nil {
+		var pgErr *pgconn.PgError
+		if errors.As(err, &pgErr) && (pgErr.Code == "22P02" || pgErr.Code == "22007") {
+			domainErr = domain.NewDomainError(err, domain.ErrValidation, "format", pgErr.Message)
+			return
+		}
+		domainErr = domain.NewUnexpectedError(err)
+		return
+	}
+	if commandTag.RowsAffected() == 0 {
+		domainErr = domain.NewDomainError(err, domain.ErrFileNotFound, file_id)
+		return
+	}
+	return
+}

backend/internal/infrastructure/persistence/postgres/utils.go

@@ -1,21 +1,52 @@
 package postgres
 
 import (
+	"errors"
 	"fmt"
 	"net/http"
 	"strconv"
 	"strings"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/jackc/pgx/v5/pgconn"
 )
 
+// Handle database error
+func handleDBError(errIn error) (statusCode int, err error) {
+	if errIn == nil {
+		statusCode = http.StatusOK
+		return
+	}
+	if errors.Is(errIn, pgx.ErrNoRows) {
+		err = fmt.Errorf("not found")
+		statusCode = http.StatusNotFound
+		return
+	}
+	var pgErr *pgconn.PgError
+	if errors.As(errIn, &pgErr) {
+		switch pgErr.Code {
+		case "22P02", "22007": // Invalid data format
+			err = fmt.Errorf("%s", pgErr.Message)
+			statusCode = http.StatusBadRequest
+			return
+		case "23505": // Unique constraint violation
+			err = fmt.Errorf("already exists")
+			statusCode = http.StatusConflict
+			return
+		}
+	}
+	return http.StatusInternalServerError, errIn
+}
+
 // Convert "filter" URL param to SQL "WHERE" condition
-func filterToSQL(filter string) (sql string, statusCode int, err error) {
+func filterToSQL(filter string) (sql string, err error) {
 	// filterTokens := strings.Split(string(filter), ";")
 	sql = "(true)"
 	return
 }
 
 // Convert "sort" URL param to SQL "ORDER BY"
-func sortToSQL(sort string) (sql string, statusCode int, err error) {
+func sortToSQL(sort string) (sql string, err error) {
 	if sort == "" {
 		return
 	}
@@ -32,7 +63,6 @@ func sortToSQL(sort string) (sql string, statusCode int, err error) {
 			sortOrder = "DESC"
 		default:
 			err = fmt.Errorf("invalid sorting order mark: %q", sortOrder)
-			statusCode = http.StatusBadRequest
 			return
 		}
 		// validate sorting column
@@ -40,7 +70,6 @@ func sortToSQL(sort string) (sql string, statusCode int, err error) {
 		n, err = strconv.Atoi(sortColumn)
 		if err != nil || n < 0 {
 			err = fmt.Errorf("invalid sorting column: %q", sortColumn)
-			statusCode = http.StatusBadRequest
 			return
 		}
 		// add sorting option to query

backend/internal/interfaces/rest/handlers/error_handler.go

@@ -0,0 +1,44 @@
+package rest
+
+import (
+	"fmt"
+	"net/http"
+
+	"tanabata/internal/domain"
+)
+
+type ErrorResponse struct {
+	Error   string `json:"error"`
+	Code    string `json:"code,omitempty"`
+	Message string `json:"message,omitempty"`
+}
+
+type ErrorMapper struct{}
+
+func (m *ErrorMapper) MapError(err domain.DomainError) (int, ErrorResponse) {
+	switch err.Code {
+	case domain.ErrFileNotFound:
+		return http.StatusNotFound, ErrorResponse{
+			Error:   "Not Found",
+			Code:    string(err.Code),
+			Message: fmt.Sprintf("File %q not found", err.Details...),
+		}
+	case domain.ErrMIMENotSupported:
+		return http.StatusNotFound, ErrorResponse{
+			Error:   "MIME not supported",
+			Code:    string(err.Code),
+			Message: fmt.Sprintf("MIME not supported: %q", err.Details...),
+		}
+	case domain.ErrValidation:
+		return http.StatusNotFound, ErrorResponse{
+			Error:   "Bad Request",
+			Code:    string(err.Code),
+			Message: fmt.Sprintf("Invalid %s: %s", err.Details...),
+		}
+	}
+	return http.StatusInternalServerError, ErrorResponse{
+		Error:   "Internal Server Error",
+		Code:    string(err.Code),
+		Message: "An unexpected error occured",
+	}
+}

backend/internal/storage/postgres/files.go

@@ -1,259 +0,0 @@
-package postgres
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"net/http"
-	"time"
-
-	"github.com/jackc/pgx/v5"
-
-	"tanabata/internal/domain"
-)
-
-// Check if user can view file
-func FileGetAccess(user_id int, file_id string) (canView, canEdit bool, err error) {
-	ctx := context.Background()
-	row := connPool.QueryRow(ctx, `
-		SELECT 
-			COALESCE(a.view, FALSE) OR f.creator_id=$1 OR COALESCE(u.is_admin, FALSE),
-			COALESCE(a.edit, FALSE) OR f.creator_id=$1 OR COALESCE(u.is_admin, FALSE)
-		FROM data.files f
-		LEFT JOIN acl.files a ON a.file_id=f.id AND a.user_id=$1
-		LEFT JOIN system.users u ON u.id=$1
-		WHERE f.id=$2
-		`, user_id, file_id)
-	err = row.Scan(&canView, &canEdit)
-	return
-}
-
-// Get a set of files
-func FileGetSlice(user_id int, filter, sort string, limit, offset int) (files domain.Slice[domain.FileItem], statusCode int, err error) {
-	filterCond, statusCode, err := filterToSQL(filter)
-	if err != nil {
-		return
-	}
-	sortExpr, statusCode, err := sortToSQL(sort)
-	if err != nil {
-		return
-	}
-	// prepare query
-	query := `
-	SELECT
-		f.id,
-		f.name,
-		m.name,
-		m.extension,
-		uuid_extract_timestamp(f.id),
-		u.name,
-		u.is_admin
-	FROM data.files f
-	JOIN system.mime m ON m.id=f.mime_id
-	JOIN system.users u ON u.id=f.creator_id
-	WHERE NOT f.is_deleted AND (f.creator_id=$1 OR (SELECT view FROM acl.files WHERE file_id=f.id AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1)) AND
-	`
-	query += filterCond
-	queryCount := query
-	query += sortExpr
-	if limit >= 0 {
-		query += fmt.Sprintf(" LIMIT %d", limit)
-	}
-	if offset > 0 {
-		query += fmt.Sprintf(" OFFSET %d", offset)
-	}
-	// execute query
-	statusCode, err = transaction(func(ctx context.Context, tx pgx.Tx) (statusCode int, err error) {
-		rows, err := tx.Query(ctx, query, user_id)
-		if err != nil {
-			statusCode, err = handleDBError(err)
-			return
-		}
-		defer rows.Close()
-		count := 0
-		for rows.Next() {
-			var file domain.FileItem
-			err = rows.Scan(&file.ID, &file.Name, &file.MIME.Name, &file.MIME.Extension, &file.CreatedAt, &file.Creator.Name, &file.Creator.IsAdmin)
-			if err != nil {
-				statusCode = http.StatusInternalServerError
-				return
-			}
-			files.Data = append(files.Data, file)
-			count++
-		}
-		err = rows.Err()
-		if err != nil {
-			statusCode = http.StatusInternalServerError
-			return
-		}
-		files.Pagination.Limit = limit
-		files.Pagination.Offset = offset
-		files.Pagination.Count = count
-		row := tx.QueryRow(ctx, fmt.Sprintf("SELECT COUNT(*) FROM (%s) tmp", queryCount), user_id)
-		err = row.Scan(&files.Pagination.Total)
-		if err != nil {
-			statusCode = http.StatusInternalServerError
-		}
-		return
-	})
-	if err == nil {
-		statusCode = http.StatusOK
-	}
-	return
-}
-
-// Get file
-func FileGet(user_id int, file_id string) (file domain.FileFull, statusCode int, err error) {
-	ctx := context.Background()
-	row := connPool.QueryRow(ctx, `
-		SELECT
-			f.id,
-			f.name,
-			m.name,
-			m.extension,
-			uuid_extract_timestamp(f.id),
-			u.name,
-			u.is_admin,
-			f.notes,
-			f.metadata,
-			(SELECT COUNT(*) FROM activity.file_views fv WHERE fv.file_id=$2 AND fv.user_id=$1)
-		FROM data.files f
-		JOIN system.mime m ON m.id=f.mime_id
-		JOIN system.users u ON u.id=f.creator_id
-		WHERE NOT f.is_deleted AND f.id=$2 AND (f.creator_id=$1 OR (SELECT view FROM acl.files WHERE file_id=$2 AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))
-		`, user_id, file_id)
-	err = row.Scan(&file.ID, &file.Name, &file.MIME.Name, &file.MIME.Extension, &file.CreatedAt, &file.Creator.Name, &file.Creator.IsAdmin, &file.Notes, &file.Metadata, &file.Viewed)
-	if err != nil {
-		statusCode, err = handleDBError(err)
-		return
-	}
-	rows, err := connPool.Query(ctx, `
-		SELECT
-			t.id,
-			t.name,
-			COALESCE(t.color, c.color)
-		FROM data.tags t
-		LEFT JOIN data.categories c ON c.id=t.category_id
-		JOIN data.file_tag ft ON ft.tag_id=t.id
-		WHERE ft.file_id=$1
-		`, file_id)
-	if err != nil {
-		statusCode, err = handleDBError(err)
-		return
-	}
-	defer rows.Close()
-	for rows.Next() {
-		var tag domain.TagCore
-		err = rows.Scan(&tag.ID, &tag.Name, &tag.Color)
-		if err != nil {
-			statusCode = http.StatusInternalServerError
-			return
-		}
-		file.Tags = append(file.Tags, tag)
-	}
-	err = rows.Err()
-	if err != nil {
-		statusCode = http.StatusInternalServerError
-		return
-	}
-	statusCode = http.StatusOK
-	return
-}
-
-// Add file
-func FileAdd(user_id int, name, mime string, datetime time.Time, notes string, metadata json.RawMessage) (file domain.FileCore, statusCode int, err error) {
-	ctx := context.Background()
-	var mime_id int
-	var extension string
-	row := connPool.QueryRow(ctx, "SELECT id, extension FROM system.mime WHERE name=$1", mime)
-	err = row.Scan(&mime_id, &extension)
-	if err != nil {
-		if err == pgx.ErrNoRows {
-			err = fmt.Errorf("unsupported file type: %q", mime)
-			statusCode = http.StatusBadRequest
-		} else {
-			statusCode, err = handleDBError(err)
-		}
-		return
-	}
-	row = connPool.QueryRow(ctx, `
-	INSERT INTO data.files (name, mime_id, datetime, creator_id, notes, metadata)
-	VALUES (NULLIF($1, ''), $2, $3, $4, NULLIF($5 ,''), $6)
-	RETURNING id
-	`, name, mime_id, datetime, user_id, notes, metadata)
-	err = row.Scan(&file.ID)
-	if err != nil {
-		statusCode, err = handleDBError(err)
-		return
-	}
-	file.Name.String = name
-	file.Name.Valid = (name != "")
-	file.MIME.Name = mime
-	file.MIME.Extension = extension
-	statusCode = http.StatusOK
-	return
-}
-
-// Update file
-func FileUpdate(user_id int, file_id string, updates map[string]interface{}) (statusCode int, err error) {
-	if len(updates) == 0 {
-		err = fmt.Errorf("no fields provided for update")
-		statusCode = http.StatusBadRequest
-		return
-	}
-	writableFields := map[string]bool{
-		"name":     true,
-		"datetime": true,
-		"notes":    true,
-		"metadata": true,
-	}
-	query := "UPDATE data.files SET"
-	newValues := []interface{}{user_id}
-	count := 2
-	for field, value := range updates {
-		if !writableFields[field] {
-			err = fmt.Errorf("invalid field: %q", field)
-			statusCode = http.StatusBadRequest
-			return
-		}
-		query += fmt.Sprintf(" %s=NULLIF($%d, '')", field, count)
-		newValues = append(newValues, value)
-		count++
-	}
-	query += fmt.Sprintf(
-		" WHERE id=$%d AND (creator_id=$1 OR (SELECT edit FROM acl.files WHERE file_id=$%d AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))",
-		count, count)
-	newValues = append(newValues, file_id)
-	ctx := context.Background()
-	commandTag, err := connPool.Exec(ctx, query, newValues...)
-	if err != nil {
-		statusCode, err = handleDBError(err)
-		return
-	}
-	if commandTag.RowsAffected() == 0 {
-		err = fmt.Errorf("not found")
-		statusCode = http.StatusNotFound
-		return
-	}
-	statusCode = http.StatusNoContent
-	return
-}
-
-// Delete file
-func FileDelete(user_id int, file_id string) (statusCode int, err error) {
-	ctx := context.Background()
-	commandTag, err := connPool.Exec(ctx,
-		"DELETE FROM data.files WHERE id=$2 AND (creator_id=$1 OR (SELECT edit FROM acl.files WHERE file_id=$2 AND user_id=$1) OR (SELECT is_admin FROM system.users WHERE id=$1))",
-		user_id, file_id)
-	if err != nil {
-		statusCode, err = handleDBError(err)
-		return
-	}
-	if commandTag.RowsAffected() == 0 {
-		err = fmt.Errorf("not found")
-		statusCode = http.StatusNotFound
-		return
-	}
-	statusCode = http.StatusNoContent
-	return
-}

backend/internal/storage/postgres/store.go

@@ -1,79 +0,0 @@
-package postgres
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net/http"
-	"time"
-
-	"github.com/jackc/pgx/v5"
-	"github.com/jackc/pgx/v5/pgconn"
-	"github.com/jackc/pgx/v5/pgxpool"
-)
-
-var connPool *pgxpool.Pool
-
-func InitDB(connString string) error {
-	poolConfig, err := pgxpool.ParseConfig(connString)
-	if err != nil {
-		return fmt.Errorf("error while parsing connection string: %w", err)
-	}
-
-	poolConfig.MaxConns = 100
-	poolConfig.MinConns = 0
-	poolConfig.MaxConnLifetime = time.Hour
-	poolConfig.HealthCheckPeriod = 30 * time.Second
-
-	connPool, err = pgxpool.NewWithConfig(context.Background(), poolConfig)
-	if err != nil {
-		return fmt.Errorf("error while initializing DB connections pool: %w", err)
-	}
-	return nil
-}
-
-func transaction(handler func(context.Context, pgx.Tx) (statusCode int, err error)) (statusCode int, err error) {
-	ctx := context.Background()
-	tx, err := connPool.Begin(ctx)
-	if err != nil {
-		statusCode = http.StatusInternalServerError
-		return
-	}
-	statusCode, err = handler(ctx, tx)
-	if err != nil {
-		tx.Rollback(ctx)
-		return
-	}
-	err = tx.Commit(ctx)
-	if err != nil {
-		statusCode = http.StatusInternalServerError
-	}
-	return
-}
-
-// Handle database error
-func handleDBError(errIn error) (statusCode int, err error) {
-	if errIn == nil {
-		statusCode = http.StatusOK
-		return
-	}
-	if errors.Is(errIn, pgx.ErrNoRows) {
-		err = fmt.Errorf("not found")
-		statusCode = http.StatusNotFound
-		return
-	}
-	var pgErr *pgconn.PgError
-	if errors.As(errIn, &pgErr) {
-		switch pgErr.Code {
-		case "22P02", "22007": // Invalid data format
-			err = fmt.Errorf("%s", pgErr.Message)
-			statusCode = http.StatusBadRequest
-			return
-		case "23505": // Unique constraint violation
-			err = fmt.Errorf("already exists")
-			statusCode = http.StatusConflict
-			return
-		}
-	}
-	return http.StatusInternalServerError, errIn
-}