Replace Paste.Content field by P.URL and FU.PasteID

internal/db/db.go

@@ -35,7 +35,11 @@ var (
 		LogLevel:      logger.Warn,
 		Colorful:      true,
 	})
-	gormConfig = gorm.Config{Logger: gormLogger, PrepareStmt: true}
+	gormConfig = gorm.Config{
+		Logger:                                   gormLogger,
+		PrepareStmt:                              true,
+		DisableForeignKeyConstraintWhenMigrating: true,
+	}
 )
 
 // OpenDBFromEnvironment tries to open an SQL database, described by

internal/db/fileupload.go

@@ -38,6 +38,8 @@ type FileUpload struct {
 	// UUID publically identifies this FileUpload.
 	PubID uuid.UUID `gorm:"uniqueIndex"`
 
+	PasteID uint
+
 	// FileName contains the original filename of this FileUpload.
 	FileName string
 

internal/db/migrate.go

@@ -38,8 +38,69 @@ func Gormigrate(db *gorm.DB) *gormigrate.Gormigrate {
 				}
 				return tx.AutoMigrate(&FileUpload{}, &Paste{})
 			},
-			Rollback: func(tx *gorm.DB) error {
-				return tx.Migrator().DropTable(&FileUpload{}, &Paste{})
+		},
+		{
+			ID: "202107231722",
+			Migrate: func(tx *gorm.DB) error {
+				// Update the schema
+				type FileUpload struct {
+					ID          uint            `gorm:"primaryKey"`
+					State       FileUploadState `gorm:"index"`
+					PubID       uuid.UUID       `gorm:"uniqueIndex"`
+					PasteID     uint
+					FileName    string
+					ContentType string
+					Checksum    uint32
+					CreatedAt   time.Time
+					UpdatedAt   time.Time
+					DeletedAt   gorm.DeletedAt
+				}
+				type Paste struct {
+					ID          uint       `gorm:"primaryKey"`
+					Type        PasteType  `gorm:"index"`
+					State       PasteState `gorm:"index"`
+					Content     []byte
+					URL         string
+					FileUpload  *FileUpload
+					Key         string `gorm:"uniqueIndex"`
+					DeleteToken string
+					CreatedAt   time.Time
+					UpdatedAt   time.Time
+					DeletedAt   gorm.DeletedAt
+				}
+				err := tx.AutoMigrate(&FileUpload{}, &Paste{})
+				if err != nil {
+					return err
+				}
+
+				// Migrate the data
+				pastes := make([]Paste, 0)
+				if err := tx.Model(&Paste{}).Find(&pastes).Error; err != nil {
+					return err
+				}
+				for _, p := range pastes {
+					switch p.Type {
+					case PasteTypeRedirect:
+						p.URL = string(p.Content)
+						tx.Model(p).Select("Content", "URL").Updates(p)
+					case PasteTypeFileUpload:
+						var id uuid.UUID
+						var fus []FileUpload
+						copy(id[:], p.Content)
+						if err := db.Unscoped().Limit(1).Where("pub_id = ?", id).Find(&fus).Error; err != nil {
+							return err
+						}
+						p.FileUpload = &fus[0]
+						tx.Model(p).Select("Content", "FileUpload").Updates(p)
+					default:
+						continue
+					}
+				}
+
+				// Currently there is a bug in GORM, which causes a nil ptr
+				// dereference when you try dropping a column in an sqlite3
+				// database.
+				return nil
 			},
 		},
 	})

internal/db/paste.go

@@ -8,9 +8,9 @@ import (
 	"strings"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/pkg/errors"
 	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
 )
 
 // PasteType describes the type of Paste (i.e. file, redirect, [...]).
@@ -24,7 +24,8 @@ type Paste struct {
 	ID          uint       `gorm:"primaryKey"`
 	Type        PasteType  `gorm:"index"`
 	State       PasteState `gorm:"index"`
-	Content     []byte
+	URL         string
+	FileUpload  *FileUpload
 	Key         string `gorm:"uniqueIndex"`
 	DeleteToken string
 	CreatedAt   time.Time
@@ -146,7 +147,7 @@ func ValidatePasteKey(key string) error {
 // the key format first.
 func GetPasteNoValidate(db *gorm.DB, key string) (*Paste, error) {
 	var ps []Paste
-	if err := db.Unscoped().Limit(1).Where("key = ?", key).Find(&ps).Error; err != nil {
+	if err := db.Unscoped().Preload(clause.Associations).Where("key = ?", key).Find(&ps).Error; err != nil {
 		return nil, err
 	}
 	if len(ps) == 0 {
@@ -163,16 +164,8 @@ func (p *Paste) Save(db *gorm.DB) error {
 // Delete deletes this Paste from the database.
 func (p *Paste) Delete(db *gorm.DB, fs *FileStore) error {
 	// Remove the (maybe) attached file
-	if p.Type == PasteTypeFileUpload {
-		fuID, err := uuid.FromBytes(p.Content)
-		if err != nil {
-			return errors.Wrap(err, "failed to parse uuid")
-		}
-		fu, err := GetFileUpload(db, fuID)
-		if err != nil {
-			return errors.Wrap(err, "failed to find file in database")
-		}
-		if err := fu.Delete(db, fs); err != nil {
+	if p.FileUpload != nil {
+		if err := p.FileUpload.Delete(db, fs); err != nil {
 			return errors.Wrap(err, "failed to remove file")
 		}
 	}
@@ -180,7 +173,9 @@ func (p *Paste) Delete(db *gorm.DB, fs *FileStore) error {
 	// Wipe the old paste
 	p.Type = PasteTypeUndef
 	p.State = PasteStateDeleted
-	p.Content = []byte{}
+	p.URL = ""
+	p.FileUpload = nil
+
 	if err := db.Save(&p).Error; err != nil {
 		return errors.Wrap(err, "failed to wipe paste in database")
 	}
@@ -199,10 +194,9 @@ func (p *Paste) RedirectURL() *url.URL {
 	if p.Type != PasteTypeRedirect {
 		panic("expected p.Type to be PasteTypeRedirect")
 	}
-	rawurl := string(p.Content)
-	urlParse, err := url.Parse(rawurl)
+	urlParse, err := url.Parse(p.URL)
 	if err != nil {
-		panic(errors.Wrapf(err, "invalid URL ('%v') in database for key '%v'", rawurl, p.Key))
+		panic(errors.Wrapf(err, "invalid URL ('%v') in database for key '%v'", p.URL, p.Key))
 	}
 	return urlParse
 }