How to check if python package is latest version p

问题:

How do you check if a package is at its latest version programmatically in a script and return a true or false?

I can check with a script like this:

package='gekko'
import pip
if hasattr(pip, 'main'):
    from pip import main as pipmain
else:
    from pip._internal import main as pipmain
pipmain(['search','gekko'])

or with command line:

(base) C:\User>pip search gekko
gekko (0.2.3)  - Machine learning and optimization for dynamic systems
  INSTALLED: 0.2.3 (latest)

But how do I check programmatically and return true or false?

回答1:

Fast Version (Checking the package only)

The code below calls the package with an unavailable version like pip install package_name==random. The call returns all the available versions. The program reads the latest version.

The program then runs pip show package_name and gets the current version of the package.

If it finds a match, it returns True, otherwise False.

This is a reliable option given that it stands on pip

import subprocess
import sys
def check(name):
    latest_version = str(subprocess.run([sys.executable, '-m', 'pip', 'install', '{}==random'.format(name)], capture_output=True, text=True))
    latest_version = latest_version[latest_version.find('(from versions:')+15:]
    latest_version = latest_version[:latest_version.find(')')]
    latest_version = latest_version.replace(' ','').split(',')[-1]

    current_version = str(subprocess.run([sys.executable, '-m', 'pip', 'show', '{}'.format(name)], capture_output=True, text=True))
    current_version = current_version[current_version.find('Version:')+8:]
    current_version = current_version[:current_version.find('\\n')].replace(' ','') 

    if latest_version == current_version:
        return True
    else:
        return False

The following code calls for pip list --outdated:

import subprocess
import sys

def check(name):
    reqs = subprocess.check_output([sys.executable, '-m', 'pip', 'list','--outdated'])
    outdated_packages = [r.decode().split('==')[0] for r in reqs.split()]
    return name in outdated_packages

回答2:

My project johnnydep has this feature.

In shell:

pip install --upgrade pip johnnydep
pip install gekko==0.2.0

In Python:

>>> from johnnydep.lib import JohnnyDist
>>> dist = JohnnyDist("gekko")
>>> dist.version_installed  
'0.2.0'
>>> dist.version_latest 
'0.2.3'

回答3:

Edit: Remove pip search

Thanks for the several suggestions. Here is a new version that doesn't use pip search but instead pulls the latest version directly from pypi as proposed by Daniel Hill. This also resolves the issue with the substring false matches.

def check(name):
    import subprocess
    import sys
    import json
    import urllib.request

    # create dictionary of package versions
    pkgs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze'])
    keys = [p.decode().split('==')[0] for p in pkgs.split()]
    values = [p.decode().split('==')[1] for p in pkgs.split()]
    d = dict(zip(keys, values)) # dictionary of all package versions

    # retrieve info on latest version
    contents = urllib.request.urlopen('https://pypi.org/pypi/'+name+'/json').read()
    data = json.loads(contents)
    latest_version = data['info']['version']

    if d[name]==latest_version:
        print('Latest version (' + d[name] + ') of '+str(name)+' is installed')
        return True
    else:
        print('Version ' + d[name] + ' of '+str(name)+' not the latest '+latest_version)
        return False

print(check('gekko'))

Original Response

Here is a fast solution that retrieves latest version information on only the gekko package of interest.

def check(name):
    import subprocess
    import sys
    # create dictionary of package versions
    pkgs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze'])
    keys = [p.decode().split('==')[0] for p in pkgs.split()]
    values = [p.decode().split('==')[1] for p in pkgs.split()]
    d = dict(zip(keys, values)) # dictionary of all package versions

    # retrieve info on latest version
    s = subprocess.check_output([sys.executable, '-m', 'pip', 'search', name])

    if d[name] in s.decode():  # weakness
        print('Latest version (' + d[name] + ') of '+str(name)+' is installed')
        return True
    else:
        print(s.decode())
        return False

print(check('gekko'))

This produces the message Latest version (0.2.3) of gekko is installed and returns True to indicate latest version (or False if not the latest version). This may not be the best solution because it only checks for a version substring with if d[name] in s.decode(): but it is faster than pip list --outdated that checks all the packages. This isn't the most reliable method because it will return an incorrect True if current installed version is 0.2.3 but latest version is 0.2.30 or 0.2.3a. An improvement would be to programmatically get the latest version and do a direct comparison.

回答4:

Latest version:

My project luddite has this feature:

>>> import luddite
>>> luddite.get_version_pypi("gekko")
'0.2.3'

Installed version:

The canonical way to check installed version is just to access the __version__ attribute of the top-level namespace:

>>> import gekko
>>> gekko.__version__
'0.2.0'

Unfortunately not all projects set this attribute. When they don't, you can use pkg_resources to dig it out from the metadata:

>>> import pkg_resources
>>> pkg_resources.get_distribution("gekko").version
'0.2.0'

回答5:

This should do the trick at least for demo purposes. Simply call isLatestVersion with the name of the package you would like to check. If you are using this somewhere important you would want to try/catch the url request as internet access may not be available. Also note that if the package is not installed isLatestVersion will return False.

This is tested for Python 3.7.4 and Pip 19.0.3.

import pip
import subprocess
import json
import urllib.request
from pip._internal.operations.freeze import freeze

def isLatestVersion(pkgName):
    # Get the currently installed version
    current_version = ''
    for requirement in freeze(local_only=False):
        pkg = requirement.split('==')
        if pkg[0] == pkgName:
            current_version = pkg[1]

    # Check pypi for the latest version number
    contents = urllib.request.urlopen('https://pypi.org/pypi/'+pkgName+'/json').read()
    data = json.loads(contents)
    latest_version = data['info']['version']

    return latest_version == current_version

回答6:

It's not hard to write a simple script yourself by querying the PyPI API. With the latest Python 3.8, it's possible using only the standard library (when using Python 3.7 or older, you'll have to install the importlib_metadata backport):

# check_version.py

import json
import urllib.request
import sys

try:
    from importlib.metadata import version
except ImportError:
    from importlib_metadata import version

from distutils.version import LooseVersion


if __name__ == '__main__':
    name = sys.argv[1]
    installed_version = LooseVersion(version(name))

    # fetch package metadata from PyPI
    pypi_url = f'https://pypi.org/pypi/{name}/json'
    response = urllib.request.urlopen(pypi_url).read().decode()
    latest_version = max(LooseVersion(s) for s in json.loads(response)['releases'].keys())

    print('package:', name, 'installed:', installed_version, 'latest:', latest_version)

Usage example:

$ python check_version.py setuptools
package: setuptools installed: 41.2.0 latest: 41.6.0

If you're happen to have packaging installed, it's a better alternative to distutils.version for version parsing:

from distutils.version import LooseVersion

...

LooseVersion(s)

becomes

from packaging.version import parse

...

parse(s)