Memory Tempfile

2.2.3 · active · verified Thu Apr 16

memory-tempfile (version 2.2.3) is a Python library that provides helper functions to identify and utilize paths on Linux-based operating systems where RAM-based temporary files can be created. It extends Python's standard `tempfile` module to prioritize memory-backed filesystems like `tmpfs` or `ramfs` for temporary storage, aiming to improve performance by avoiding disk I/O. The project has a stable, albeit infrequent, release history with the current version released in 2019.

Common errors

```
RuntimeError: No suitable memory-based tempdir found
```
cause This error occurs when `memory-tempfile` cannot locate an existing and accessible memory-backed filesystem (like tmpfs or ramfs) to use for temporary files, and the `fallback` option was explicitly set to `False`.

fix Initialize `MemoryTempfile` with `fallback=True` to allow it to use the system's default temporary directory if a memory-based one isn't available: `tempfile_manager = MemoryTempfile(fallback=True)`. Alternatively, provide a specific fallback path: `tempfile_manager = MemoryTempfile(fallback='/var/tmp')`.
```
Permission denied: '/run/user/1000/...' (or similar path)
```
cause Despite being a memory-based path, underlying filesystem permissions can still prevent the user from creating or writing files. This could be due to incorrect user permissions or restrictive system configurations.

fix Verify the permissions of the identified temporary directory (e.g., `/run/user/<your_uid>`, `/dev/shm`) for the user running the Python process. If using custom `preferred_paths` or `additional_paths`, ensure those directories are writable. As a workaround, consider using the `fallback=True` option or specifying a known writable directory via `dir` argument to `TemporaryFile` or `TemporaryDirectory`.
```
IOError: [Errno 28] No space left on device
```
cause Even though `memory-tempfile` uses RAM-based filesystems, these filesystems typically have a configured size limit. If too many or too large temporary files are created, this limit can be exhausted, leading to 'no space left' errors.

fix Monitor the usage of your memory-based temporary filesystems (e.g., `df -h /dev/shm` on Linux). Ensure proper cleanup of temporary files, especially when not using context managers. If large files are expected, increase the size limit of the tmpfs mount (usually done via `/etc/fstab`) or consider `fallback=True`.

Warnings

gotcha The `memory-tempfile` library is currently designed and tested for Linux-only environments. Its core functionality relies on identifying and using specific Linux-based RAM filesystems (e.g., tmpfs, ramfs).
Fix: Ensure deployment on Linux systems. If cross-platform memory-backed temporary storage is needed, consider alternative solutions or platform-specific logic.
breaking If no suitable memory-based filesystem path (like tmpfs or ramfs) is found, and the `fallback` argument to `MemoryTempfile` constructor is set to `False`, a `RuntimeError` will be raised.
Fix: Set `fallback=True` to allow falling back to the default system temporary directory, or provide a specific fallback path (e.g., `fallback='/path/to/disk/temp'`). Check `MemoryTempfile().tempdir` before creating files if `fallback=False` is critical.
gotcha Paths containing the string `{uid}` (e.g., `/run/user/{uid}`) are automatically replaced by the current user's ID by the library. This behavior is intentional but developers should be aware of this dynamic path resolution.
Fix: Account for `{uid}` replacement in path expectations, especially if constructing paths manually or validating them. The resolved path can be accessed via `tempfile_manager.tempdir`.

Install

pip install memory-tempfile Install with pip

Imports

MemoryTempfile

from memory_tempfile import MemoryTempfile

Quickstart

This example demonstrates how to create a temporary file and a temporary directory using `MemoryTempfile`, which will attempt to use a RAM-based filesystem. The resources are automatically cleaned up using context managers.

from memory_tempfile import MemoryTempfile
import os

tempfile_manager = MemoryTempfile()

# Create a temporary file in a memory-backed filesystem
with tempfile_manager.TemporaryFile(mode='w+t') as tf:
    tf.write('Hello from memory tempfile!')
    tf.seek(0)
    content = tf.read()
    print(f"Read from temp file: {content}")

# Create a temporary directory in a memory-backed filesystem
with tempfile_manager.TemporaryDirectory() as td:
    print(f"Temporary directory created at: {td}")
    # You can create files inside this directory
    file_path = os.path.join(td, 'my_data.txt')
    with open(file_path, 'w') as f:
        f.write('Data in temp directory.')
    print(f"File created in temp directory: {file_path}")
# Directory and its contents are automatically removed when exiting the 'with' block

view raw JSON →