storage

type FileID string

type FileMeta struct {
	FileID           FileID    `gorm:"primaryKey;column:file_id" json:"file_id"`
	Provider         string    `gorm:"column:provider" json:"provider"`
	Identifier       string    `gorm:"column:identifier" json:"identifier"`
	OriginalFilename string    `json:"original_filename" gorm:"column:original_filename"`
	ContentType      string    `json:"content_type" gorm:"column:content_type"`
	ContentLength    int64     `json:"content_length" gorm:"column:content_length"`
	Md5Checksum      string    `json:"md5_checksum" gorm:"column:md5_checksum"`
	Finished         bool      `json:"finished" gorm:"column:finished"`
	CreatedAt        time.Time `json:"created_at" gorm:"column:created_at"`
	UpdatedAt        time.Time `json:"updated_at" gorm:"column:updated_at"`
}

type IFileMetaRepository interface {
	scene.Named
	// Store will store the metadata in the repository
	// will overwrite the old metadata if exists
	Store(meta FileMeta) error
	Load(fileId FileID) (meta FileMeta, err error)
	Delete(fileId FileID) error
	List(provider string, offset, limit int64) (model.PaginationResult[FileMeta], error)
}

type IStorageProvider interface {
	scene.Named
	// ProviderName return provider name in fileId
	ProviderName() string
	// HealthCheck will check if this Storage provider is accessible
	HealthCheck() error
	// Meta will return any possible metadata can be found, as a fallback option if IFileMetaRepository failed
	Meta(fileId FileID) (meta FileMeta, err error)
	Load(fileId FileID, offset, length int64) (reader io.ReadCloser, err error)
	LoadAll(fileId FileID) (reader io.ReadCloser, err error)
	// Store will store the data in the storage at path and return the fileId,
	// if path not exists, it will create the path.
	Store(fileId FileID, data io.Reader) (err error)
	Delete(fileId FileID) error
	// Multipart related
	InitMultipartStore(fileId FileID) (uploadId string, err error)
	StorePart(uploadId string, partNumber int, data io.Reader) error
	CompleteMultipartStore(uploadId string) error
	AbortMultipartStore(uploadId string) error
	// GetPublicURL get public url which can be access in public network
	GetPublicURL(fileId FileID) (url string, err error)
}

type IStorageService interface {
	scene.Service
	ListProviders() []string
	// ListMeta will list meta from specific provider.
	ListMeta(provider string, offset, limit int64) (model.PaginationResult[FileMeta], error)
	// Meta return the meta given a fileId
	Meta(fileId FileID) (meta FileMeta, err error)
	// Load will load file stream at offset with length.
	// Caller must close the returned reader.
	Load(fileId FileID, offset, length int64) (reader io.ReadCloser, err error)
	// LoadAll will load full file stream.
	// Caller must close the returned reader.
	LoadAll(fileId FileID) (reader io.ReadCloser, err error)
	Delete(fileId FileID) error
	// Store will store data at default provider
	// it calls StoreAt internally
	// Store consumes data from reader until EOF.
	Store(data io.Reader, meta FileMeta) (fileId FileID, err error)
	// StoreAt will store data using the given provider and identifier.
	// If provider is empty, the service default provider will be used.
	// If identifier is empty, the service will generate one internally.
	StoreAt(provider, identifier string, data io.Reader, meta FileMeta) (fileId FileID, err error)
	// Multipart related
	// InitMultipartStore will initialize a multipart upload using the given provider and identifier.
	// If provider is empty, the service default provider will be used.
	// If identifier is empty, the service will generate one internally.
	// It returns both the resolved file id and the upload id.
	InitMultipartStore(provider, identifier string, meta FileMeta) (fileId FileID, uploadId string, err error)
	StorePart(uploadId string, partNumber int, data io.Reader) error
	StorePartReader(uploadId string, partNumber int, data io.Reader) error
	CompleteMultipartStore(uploadId string) error
	AbortMultiPartStore(uploadId string) error
	// GetPublicURL get public url which can be access in public network
	GetPublicURL(fileId FileID) (url string, err error)
}

type IUploadSessionTracker interface {
	scene.Named
	Save(uploadId string, session UploadSession) error
	Get(uploadId string) (UploadSession, error)
	Delete(uploadId string) error
}

type IoInterface interface {
	io.Reader
	io.Seeker
}

type UploadSession struct {
	FileID  FileID    `json:"file_id"`
	Created time.Time `json:"created"`
}