{"record":{"id":"de30cb58e78242b1","repo":"Textualize/rich","slug":"unable-to-get-the-total-number-of-bytes-please-sp","errorCode":null,"errorMessage":"unable to get the total number of bytes, please specify 'total'","messagePattern":"unable to get the total number of bytes, please specify 'total'","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"rich/progress.py","lineNumber":1267,"sourceCode":"            total (int, optional): Total number of bytes to read. This must be provided unless a task with a total is also given.\n            task_id (TaskID): Task to track. Default is new task.\n            description (str, optional): Description of task, if new task is created.\n\n        Returns:\n            BinaryIO: A readable file-like object in binary mode.\n\n        Raises:\n            ValueError: When no total value can be extracted from the arguments or the task.\n        \"\"\"\n        # attempt to recover the total from the task\n        total_bytes: Optional[float] = None\n        if total is not None:\n            total_bytes = total\n        elif task_id is not None:\n            with self._lock:\n                total_bytes = self._tasks[task_id].total\n        if total_bytes is None:\n            raise ValueError(\n                f\"unable to get the total number of bytes, please specify 'total'\"\n            )\n\n        # update total of task or create new task\n        if task_id is None:\n            task_id = self.add_task(description, total=total_bytes)\n        else:\n            self.update(task_id, total=total_bytes)\n\n        return _Reader(file, self, task_id, close_handle=False)\n\n    @typing.overload\n    def open(\n        self,\n        file: Union[str, \"PathLike[str]\", bytes],\n        mode: Literal[\"rb\"],\n        buffering: int = -1,\n        encoding: Optional[str] = None,","sourceCodeStart":1249,"sourceCodeEnd":1285,"githubUrl":"https://github.com/Textualize/rich/blob/9d8f9a372cc5916fd4781fec207ced7ddac2f08f/rich/progress.py#L1249-L1285","documentation":"Progress.wrap_file() needs a total byte count to build a progress bar. It first uses the explicit total= argument, then falls back to the task's existing .total (when task_id= is given). If both are None it raises ValueError telling you to specify 'total'. Unlike Progress.open(), wrap_file does not stat the file for you.","triggerScenarios":"progress.wrap_file(file) with no total= and no task_id=; or progress.wrap_file(file, task_id=tid) where the referenced task was created without a total (e.g. add_task('x', total=None) or add_task with start=False and no total). Also when the caller assumed wrap_file would use file size automatically.","commonSituations":"Streaming a non-seekable object (BytesIO without total, a socket, a generator-backed file-like object) where size is unknowable; migrating from Progress.open() (which stats the file) to wrap_file() and dropping total=; using an indeterminate task and then passing it via task_id=.","solutions":["Pass total= explicitly: progress.wrap_file(file, total=expected_size, task_id=tid).","If the file is seekable, compute the size yourself: total=f.seek(0, os.SEEK_END); f.seek(0).","If size is genuinely unknown, use add_task(total=None) with the wrapper omitted — rich renders an indeterminate (spinner) bar — or track completed bytes via progress.update()."],"exampleFix":"# before\nreader = progress.wrap_file(f, task_id=tid)  # ValueError: unable to get total\n\n# after\nimport os\ntotal = os.fstat(f.fileno()).st_size\nreader = progress.wrap_file(f, total=total, task_id=tid)","handlingStrategy":"validation","validationCode":"import os\n\ndef wrap_with_total(progress, file, task_id=None, description='Reading'):\n    total = getattr(file, 'total', None)\n    if total is None and hasattr(file, 'fileno'):\n        try:\n            total = os.fstat(file.fileno()).st_size\n        except (OSError, ValueError):\n            total = 0\n    if total is None:\n        raise ValueError('cannot determine total size for wrap_file')\n    return progress.wrap_file(file, total=total, task_id=task_id, description=description)","typeGuard":null,"tryCatchPattern":"try:\n    reader = progress.wrap_file(f, task_id=tid)\nexcept ValueError:\n    # fall back to indeterminate task\n    tid = progress.add_task('reading', total=None)\n    reader = f","preventionTips":["Always pass total= to wrap_file unless you are certain the task already has one.","Prefer Progress.open() for real files — it stats the size for you.","For unknown-size streams, use an indeterminate task (total=None) instead of wrap_file."],"tags":["rich","progress","wrap-file","total-required","valueerror"],"backgroundTag":null,"analyzedSha":"9d8f9a372cc5916fd4781fec207ced7ddac2f08f","analyzedAt":"2026-08-15T03:30:11.781Z","schemaVersion":2},"datasetVersion":"2026-08-15T22:17:37.221Z"}