Prachi,
I feel your struggle. It is easier for end user to perceive Python 2 and
Python 3 as different languages, not as versions of one language. They
usually installed alongside each other; their updates are handled
separately. On most systems they have their respective shell commands:
`python2` and `python3`.
Shell command `python` can be viewed as an alias of either `python2` or
`python3`. I use an Arch Linux derivative, where `python` is `python3`.
Most other GNU/Linux OSes use `python` as an alias of `python2`. I am
not sure about MacOS. On Windows the latest Python distribution
installed overrule PATH environment variables, so it impossible to
predict the “default” Python version (2 or 3).
Luckily, virtualenv was introduced to leverage all these issues. It is
able to handle multiple isolated Python environments, where the `python`
command is set upon the creation of the environment, while the
environment-specific package dependencies are handled transparently with
pip.
But the use of pyignite should not be limited to virtualenv. There are
many cases when the use of virtualenv is discouraged or even impossible.
For example, when deploying Python app into an OS-level container or
similar isolating environment, virtualenv would be just a useless
overhead. There are also non-standard Python distributions (used mostly
on Windows) that do not support virtualenv.
I am sorry, that users who are not proficient in Python can have so many
problems with following my documentation. But still it seems obvious for
me, that all the details of organizing user's own Python environment are
out of pyignite documentation's scope. The only thing I can suggest to
improve my documentation in this regard is putting a big bold foreword
like this:
It is assumed in this document that you know how to install
and use Python 3 on your system. Please consult your OS manual pages
or documentations of your specific Python 3 distribution regarding
the details of organizing your Python 3 environment. The use of
virualenv for development with pyignite is highly recommended.
But, frankly, I have not seen such disclaimers in the wild and not sure
if it would be useful. It is very vague and do not cover any of the
potential pitfalls.
I am sorry for giving such a lengthy explanation here, though I've been
asked a very specific question. I understand you may not have time to
invest in learning virtualenv. If so, you did everything right, just use
`python3` command for launching examples:
```
$ python3 get_and_put.py
```
On 9/21/18 10:34 AM, Prachi Garg wrote:
Hi Dmitry,
Sorry, I am not familiar with Python.
So there are more issues...
1. The version on my mac remains 2.7.10 even though I tried to link to
the new version.
~$ python --version
Python 2.7.10
~$ brew unlink python && brew link --overwrite python3
Unlinking /usr/local/Cellar/python/3.7.0. <http://3.7.0.>.. 25 symlinks
removed
Linking /usr/local/Cellar/python/3.7.0. <http://3.7.0.>.. 25 symlinks
created
~$ python --version
Python 2.7.10
2. Then I tried to update /pip/, uninstall and re-install /pyignite/
~$ pip install -U pip
-bash: /Library/Frameworks/Python.framework/Versions/3.7/bin/pip: No
such file or directory
~$ pip3 install -U pip
Requirement already up-to-date: pip in
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages
(18.0)
~$ pip3 uninstall pyignite
Uninstalling pyignite-0.3.0:
Would remove:
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pyignite-0.3.0.dist-info/*
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pyignite/*
Proceed (y/n)? y
Successfully uninstalled pyignite-0.3.0
~$ pip3 install pyignite
Collecting pyignite
Using cached
https://files.pythonhosted.org/packages/f1/0f/5669cd63fb37fa2025110f61598450567d04a72c8cf5b76bb0ca20c21734/pyignite-0.3.0-py3-none-any.whl
Requirement already satisfied: attrs==18.1.0 in
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages
(from pyignite) (18.1.0)
Requirement already satisfied: typing==3.6.4 in
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages
(from pyignite) (3.6.4)
Installing collected packages: pyignite
Successfully installed pyignite-0.3.0
How can I fix this?
On Wed, Sep 19, 2018 at 6:43 PM, Dmitry Melnichuk
<dmitry.melnic...@nobitlost.com <mailto:dmitry.melnic...@nobitlost.com>>
wrote:
Prachi,
This line in your message
> Requirement already satisfied: pyignite in
> ./Downloads/ignite-python/modules/platforms/python (0.3.1)
looks like you already did an installation of pyignite in this
environment before (maybe with "pip install -e <location of
setup.py>") from 'Downloads' folder, then delete or move downloaded
copy, and than tried to install pyignite again, this time from PyPI
("pip install <package name>").
pip does not work this way. You should either undo the previous
install ("pip uninstall <package name>"), use "--update" argument
("pip install --update <package_name>"), or even better − use
virtualenv to create a disposable Python environment for every
experiment. I provided a link to virtualenv manual in the README
file and in docs, in the 'Basics → Testing' section.
> Also, the installation instruction you have provided are for unix users.
> What are the installation instructions for Windows users?
I tried to be OS-agnostic in the docs. Please tell me, what part of
my instructions does not work on Windows.
On 9/20/18 7:32 AM, Prachi Garg wrote:
Hi Dmitry,
I tried to follow the instructions for the Python thin client
installation [1].
~$ pip install pyignite
Requirement already satisfied: pyignite in
./Downloads/ignite-python/modules/platforms/python (0.3.1)
Requirement already satisfied: typing==3.6.4 in
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages
(from pyignite) (3.6.4)
Requirement already satisfied: attrs==18.1.0 in
/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages
(from pyignite) (18.1.0)
But when I try to run an example, I get an error.
~/Downloads/ignite-python/modules/platforms/python/examples$
python get_and_put.py
Traceback (most recent call last):
File "get_and_put.py", line 16, in <module>
from pyignite import Client
ImportError: No module named pyignite
What else need to be done? I am documenting the instructions on
readme.io <http://readme.io> <http://readme.io>, but I need to
be able to run a few examples first.
Also, the installation instruction you have provided are for
unix users. What are the installation instructions for Windows
users?
[1]
https://apache-ignite-binary-protocol-client.readthedocs.io/en/latest/readme.html#installation
<https://apache-ignite-binary-protocol-client.readthedocs.io/en/latest/readme.html#installation>
