Python – How to upgrade all Python packages with pip

pippython

Is it possible to upgrade all Python packages at one time with pip?

Note: that there is a feature request for this on the official issue tracker.

Best Answer

There isn't a built-in flag yet, but you can use

pip list --outdated --format=freeze | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

Note: there are infinite potential variations for this. I'm trying to keep this answer short and simple, but please do suggest variations in the comments!

In older version of pip, you can use this instead:

pip freeze --local | grep -v '^\-e' | cut -d = -f 1  | xargs -n1 pip install -U

The grep is to skip editable ("-e") package definitions, as suggested by @jawache. (Yes, you could replace grep+cut with sed or awk or perl or...).

The -n1 flag for xargs prevents stopping everything if updating one package fails (thanks @andsens).

Related Solutions

Python – How to safely create a nested directory in Python

On Python ≥ 3.5, use pathlib.Path.mkdir:

from pathlib import Path
Path("/my/directory").mkdir(parents=True, exist_ok=True)

For older versions of Python, I see two answers with good qualities, each with a small flaw, so I will give my take on it:

Try os.path.exists, and consider os.makedirs for the creation.

import os
if not os.path.exists(directory):
    os.makedirs(directory)

As noted in comments and elsewhere, there's a race condition – if the directory is created between the os.path.exists and the os.makedirs calls, the os.makedirs will fail with an OSError. Unfortunately, blanket-catching OSError and continuing is not foolproof, as it will ignore a failure to create the directory due to other factors, such as insufficient permissions, full disk, etc.

One option would be to trap the OSError and examine the embedded error code (see Is there a cross-platform way of getting information from Python’s OSError):

import os, errno

try:
    os.makedirs(directory)
except OSError as e:
    if e.errno != errno.EEXIST:
        raise

Alternatively, there could be a second os.path.exists, but suppose another created the directory after the first check, then removed it before the second one – we could still be fooled.

Depending on the application, the danger of concurrent operations may be more or less than the danger posed by other factors such as file permissions. The developer would have to know more about the particular application being developed and its expected environment before choosing an implementation.

Modern versions of Python improve this code quite a bit, both by exposing FileExistsError (in 3.3+)...

try:
    os.makedirs("path/to/directory")
except FileExistsError:
    # directory already exists
    pass

...and by allowing a keyword argument to os.makedirs called exist_ok (in 3.2+).

os.makedirs("path/to/directory", exist_ok=True)  # succeeds even if directory exists.

Python – Convert bytes to a string

You need to decode the bytes object to produce a string:

>>> b"abcde"
b'abcde'

# utf-8 is used here because it is a very common encoding, but you
# need to use the encoding your data is actually in.
>>> b"abcde".decode("utf-8") 
'abcde'

Best Answer

Related Solutions

Python – How to safely create a nested directory in Python

Python – Convert bytes to a string

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