Add support for mime types and checksums to import/export

sync/util.go

@@ -0,0 +1,147 @@
+package sync
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+
+	"github.com/safing/jess/filesig"
+	"github.com/safing/portbase/api"
+	"github.com/safing/portbase/formats/dsd"
+)
+
+// Type is the type of an export.
+type Type string
+
+// Export Types.
+const (
+	TypeProfile       = "profile"
+	TypeSettings      = "settings"
+	TypeSingleSetting = "single-setting"
+)
+
+// Export IDs.
+const (
+	ExportTargetGlobal = "global"
+)
+
+// Messages.
+var (
+	MsgNone           = ""
+	MsgValid          = "Import is valid."
+	MsgSuccess        = "Import successful."
+	MsgRequireRestart = "Import successful. Restart required for setting to take effect."
+)
+
+// ExportRequest is a request for an export.
+type ExportRequest struct {
+	From string `json:"from"`
+	Key  string `json:"key"`
+}
+
+// ImportRequest is a request to import an export.
+type ImportRequest struct {
+	// Where the export should be import to.
+	Target string `json:"target"`
+	// Only validate, but do not actually change anything.
+	ValidateOnly bool `json:"validate_only"`
+
+	RawExport string `json:"raw_export"`
+	RawMime   string `json:"raw_mime"`
+}
+
+// ImportResult is returned by successful import operations.
+type ImportResult struct {
+	RestartRequired  bool `json:"restart_required"`
+	ReplacesExisting bool `json:"replaces_existing"`
+}
+
+// Errors.
+var (
+	ErrMismatch = api.ErrorWithStatus(
+		errors.New("the supplied export cannot be imported here"),
+		http.StatusPreconditionFailed,
+	)
+	ErrSettingNotFound = api.ErrorWithStatus(
+		errors.New("setting not found"),
+		http.StatusPreconditionFailed,
+	)
+	ErrTargetNotFound = api.ErrorWithStatus(
+		errors.New("import/export target does not exist"),
+		http.StatusGone,
+	)
+	ErrUnchanged = api.ErrorWithStatus(
+		errors.New("cannot export unchanged setting"),
+		http.StatusGone,
+	)
+	ErrNotSettablePerApp = api.ErrorWithStatus(
+		errors.New("cannot be set per app"),
+		http.StatusGone,
+	)
+	ErrInvalidImportRequest = api.ErrorWithStatus(
+		errors.New("invalid import request"),
+		http.StatusUnprocessableEntity,
+	)
+	ErrInvalidSettingValue = api.ErrorWithStatus(
+		errors.New("invalid setting value"),
+		http.StatusUnprocessableEntity,
+	)
+	ErrInvalidProfileData = api.ErrorWithStatus(
+		errors.New("invalid profile data"),
+		http.StatusUnprocessableEntity,
+	)
+	ErrImportFailed = api.ErrorWithStatus(
+		errors.New("import failed"),
+		http.StatusInternalServerError,
+	)
+	ErrExportFailed = api.ErrorWithStatus(
+		errors.New("export failed"),
+		http.StatusInternalServerError,
+	)
+)
+
+func serializeExport(export any, ar *api.Request) ([]byte, error) {
+	// Serialize data.
+	data, mimeType, format, err := dsd.MimeDump(export, ar.Header.Get("Accept"))
+	if err != nil {
+		return nil, fmt.Errorf("failed to serialize data: %w", err)
+	}
+	ar.ResponseHeader.Set("Content-Type", mimeType)
+
+	// Add checksum.
+	switch format {
+	case dsd.JSON:
+		data, err = filesig.AddJSONChecksum(data)
+	case dsd.YAML:
+		data, err = filesig.AddYAMLChecksum(data, filesig.TextPlacementTop)
+	default:
+		return nil, dsd.ErrIncompatibleFormat
+	}
+	if err != nil {
+		return nil, fmt.Errorf("failed to add checksum: %w", err)
+	}
+
+	return data, nil
+}
+
+func parseExport(request *ImportRequest, export any) error {
+	format, err := dsd.MimeLoad([]byte(request.RawExport), request.RawMime, export)
+	if err != nil {
+		return fmt.Errorf("%w: failed to parse export: %w", ErrInvalidImportRequest, err)
+	}
+
+	// Verify checksum, if available.
+	switch format {
+	case dsd.JSON:
+		err = filesig.VerifyJSONChecksum([]byte(request.RawExport))
+	case dsd.YAML:
+		err = filesig.VerifyYAMLChecksum([]byte(request.RawExport))
+	default:
+		// Checksums not supported.
+	}
+	if err != nil && errors.Is(err, filesig.ErrChecksumMissing) {
+		return fmt.Errorf("failed to verify checksum: %w", err)
+	}
+
+	return nil
+}