I'm using Linux Mint 20.2 with two directories / and /home.
I used the following command to install virtualenv:
>>> sudo pip3 install virtualenv
It worked fine and it installed in the following path:
>>> virtualenv --version
virtualenv 20.0.17 from /usr/lib/python3/dist-packages/virtualenv/__init__.py
But when I tried to create an environment I got the following error:
>>> python3 -m venv article
The virtual environment was not created successfully because ensurepip is not
available. On Debian/Ubuntu systems, you need to install the python3-venv
package using the following command.
apt install python3.8-venv
You may need to use sudo with that command. After installing the python3-venv
package, recreate your virtual environment.
Failing command: ['/home/username/article_tools/article/bin/python3', '-Im', 'ensurepip', '--upgrade', '--default-pip']
When I tried to uninstall it to install it using [b]sudo apt install python3.8-venv[/b], I got the following error:
>>> sudo pip3 uninstall virtualenv
Found existing installation: virtualenv 20.0.17
Not uninstalling virtualenv at /usr/lib/python3/dist-packages, outside environment /usr
Can't uninstall 'virtualenv'. No files were found to uninstall.
How can I fix it? By fix, I mean installing virtualenv in a way that I don't get such errors.
The fundamental problem here seems to be that you are mixing up two different packages.
Python 3 comes with a built-in virtual environment module venv which is however not installed by default on Debian-based platforms. Like the error message says, apt-get install -y python3-venv will install this package, which you can then use with python3 -m venv.
virtualenv is a separate third-party package which you invoke with the command virtualenv. It's not a bad alternative, but if you are only just learning, I would suggest you simply ignore it for the time being.
I'm using virtualenv and I need to install "psycopg2".
I have done the following:
pip install http://pypi.python.org/packages/source/p/psycopg2/psycopg2-2.4.tar.gz#md5=24f4368e2cfdc1a2b03282ddda814160
And I have the following messages:
Downloading/unpacking http://pypi.python.org/packages/source/p/psycopg2/psycopg2
-2.4.tar.gz#md5=24f4368e2cfdc1a2b03282ddda814160
Downloading psycopg2-2.4.tar.gz (607Kb): 607Kb downloaded
Running setup.py egg_info for package from http://pypi.python.org/packages/sou
rce/p/psycopg2/psycopg2-2.4.tar.gz#md5=24f4368e2cfdc1a2b03282ddda814160
Error: pg_config executable not found.
Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:
python setup.py build_ext --pg-config /path/to/pg_config build ...
or with the pg_config option in 'setup.cfg'.
Complete output from command python setup.py egg_info:
running egg_info
creating pip-egg-info\psycopg2.egg-info
writing pip-egg-info\psycopg2.egg-info\PKG-INFO
writing top-level names to pip-egg-info\psycopg2.egg-info\top_level.txt
writing dependency_links to pip-egg-info\psycopg2.egg-info\dependency_links.txt
writing manifest file 'pip-egg-info\psycopg2.egg-info\SOURCES.txt'
warning: manifest_maker: standard file '-c' not found
Error: pg_config executable not found.
Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:
python setup.py build_ext --pg-config /path/to/pg_config build ...
or with the pg_config option in 'setup.cfg'.
----------------------------------------
Command python setup.py egg_info failed with error code 1
Storing complete log in C:\Documents and Settings\anlopes\Application Data\pip\p
ip.log
My question, I only need to do this to get the psycopg2 working?
python setup.py build_ext --pg-config /path/to/pg_config build ...
Note: Since a while back, there are binary wheels for Windows in PyPI, so this should no longer be an issue for Windows users. Below are solutions for Linux, Mac users, since lots of them find this post through web searches.
Option 1
Install the psycopg2-binary PyPI package instead, it has Python wheels for Linux and Mac OS.
pip install psycopg2-binary
Option 2
Install the prerequsisites for building the psycopg2 package from source:
Debian/Ubuntu
Python 3
sudo apt install libpq-dev python3-dev
You might need to install python3.8-dev or similar for e.g. Python 3.8.
Python 2
sudo apt install libpq-dev python-dev
If that's not enough, try
sudo apt install build-essential
or
sudo apt install postgresql-server-dev-all
as well before installing psycopg2 again.
CentOS 6
See Banjer's answer
macOS
See nichochar's answer
On CentOS, you need the postgres dev packages:
sudo yum install python-devel postgresql-devel
That was the solution on CentOS 6 at least.
If you're on a mac you can use homebrew
brew install postgresql
And all other options are here: http://www.postgresql.org/download/macosx/
On Mac Mavericks with Postgres.app version 9.3.2.0 RC2 I needed to use the following code after installing Postgres:
sudo PATH=$PATH:/Applications/Postgres.app/Contents/Versions/9.3/bin pip install psycopg2
I recently configured psycopg2 on a windows machine. The easiest install is using a windows executable binary. You can find it at http://stickpeople.com/projects/python/win-psycopg/.
To install the native binary in a virtual envrionment, use easy_install:
C:\virtualenv\Scripts\> activate.bat
(virtualenv) C:\virtualenv\Scripts\> easy_install psycopg2-2.5.win32-py2.7-pg9.2.4-release.exe
For Python 3 you should use sudo apt-get install libpq-dev python3-dev under Debian.
This is what worked for me (On RHEL, CentOS:
sudo yum install postgresql postgresql-devel python-devel
And now include the path to your postgresql binary dir with you pip install:
sudo PATH=$PATH:/usr/pgsql-9.3/bin/ pip install psycopg2
Make sure to include the correct path. Thats all :)
UPDATE: For python 3, please install python3-devel instead of python-devel
The answers so far are too much like magic recipes. The error that you received tells you that pip cannot find a needed part of the PostgreSQL Query library. Possibly this is because you have it installed in a non-standard place for your OS which is why the message suggests using the --pg-config option.
But a more common reason is that you don't have libpq installed at all. This commonly happens on machines where you do NOT have PostgreSQL server installed because you only want to run client apps, not the server itself. Each OS/distro is different, for instance on Debian/Ubuntu you need to install libpq-dev. This allows you to compile and link code against the PostgreSQL Query library.
Most of the answers also suggest installing a Python dev library. Be careful. If you are only using the default Python installed by your distro, that will work, but if you have a newer version, it could cause problems. If you have built Python on this machine then you already have the dev libraries needed for compiling C/C++ libraries to interface with Python. As long as you are using the correct pip version, the one installed in the same bin folder as the python binary, then you are all set. No need to install the old version.
If you using Mac OS, you should install PostgreSQL from source.
After installation is finished, you need to add this path using:
export PATH=/local/pgsql/bin:$PATH
or you can append the path like this:
export PATH=.../:usr/local/pgsql/bin
in your .profile file or .zshrc file.
This maybe vary by operating system.
You can follow the installation process from http://www.thegeekstuff.com/2009/04/linux-postgresql-install-and-configure-from-source/
On Debian/Ubuntu:
First install and build dependencies of psycopg2 package:
# apt-get build-dep python-psycopg2
Then in your virtual environment, compile and install psycopg2 module:
(env)$ pip install psycopg2
Run below commands and you should be fine
$ apt-get update
$ apt install python3-dev libpq-dev
$ pip3 install psycopg2
I've done this before where in windows you install first into your base python installation.
Then, you manually copy the installed psycopg2 to the virtualenv install.
It's not pretty, but it works.
Before you can install psycopg2 you will need to install the python-dev package.
If you're working from Linux (and possibly other systems but i can't speak from experience) you will need to make sure to be quite exact about what version of python your running when installing the dev package.
For example when I used the command:
sudo apt-get install python3-dev
I still ran into the same error when trying to
pip install psycopg2
As I am using python 3.7 I needed to use the command
sudo apt-get install python3.7-dev
Once I did this I ran into no more issues. Obviously if your on python version 3.5 you would change that 7 to a 5.
Besides installing the required packages, I also needed to manually add PostgreSQL bin directory to PATH.
$vi ~/.bash_profile
Add PATH=/usr/pgsql-9.2/bin:$PATH before export PATH.
$source ~/.bash_profile
$pip install psycopg2
For MacOS,
Use the below command to install psycopg2, works like charm!!!
env LDFLAGS="-I/usr/local/opt/openssl/include -L/usr/local/opt/openssl/lib" pip install psycopg2
On windows XP you get this error if postgres is not installed ...
I installed Postgresql92 using the RedHat / CentOS repository on PG's downloads site http://www.postgresql.org/download/linux/redhat/
To get pg_config, I had to add /usr/pgsql-9.2/bin to PATH.
On Fedora 24: For Python 3.x
sudo dnf install postgresql-devel python3-devel
sudo dnf install redhat-rpm-config
Activate your Virtual Environment:
pip install psycopg2
Psycopg2 Depends on Postgres Libraries.
On Ubuntu You can use:
apt-get install libpq-dev
Then:
pip install psycopg2
I've been battling with this for days, and have finally figured out how to get the "pip install psycopg2" command to run in a virtualenv in Windows (running Cygwin).
I was hitting the "pg_config executable not found." error, but I had already downloaded and installed postgres in Windows. It installed in Cygwin as well; running "which pg_config" in Cygwin gave "/usr/bin/pg_config", and running "pg_config" gave sane output -- however the version installed with Cygwin is:
VERSION = PostgreSQL 8.2.11
This won't work with the current version of psycopg2, which appears to require at least 9.1. When I added "c:\Program Files\PostgreSQL\9.2\bin" to my Windows path, the Cygwin pip installer was able to find the correct version of PostgreSQL, and I was able to successfully install the module using pip. (This is probably preferable to using the Cygwin version of PostgreSQL anyway, as the native version will run much quicker).
On OpenSUSE 13.2, this fixed it:
sudo zypper in postgresql-devel
For lowly Windows users were stuck having to install psycopg2 from the link below, just install it to whatever Python installation you have setup. It will place the folder named "psycopg2" in the site-packages folder of your python installation.
After that, just copy that folder to the site-packages directory of your virtualenv and you will have no problems.
here is the link you can find the executable to install psycopg2
http://www.lfd.uci.edu/~gohlke/pythonlibs/
On Ubuntu I just needed the postgres dev package:
sudo apt-get install postgresql-server-dev-all
*Tested in a virtualenv
I could install it in a windows machine and using Anaconda/Spyder with python 2.7 through the following commands:
!pip install psycopg2
Then to establish the connection to the database:
import psycopg2
conn = psycopg2.connect(dbname='dbname',host='host_name',port='port_number', user='user_name', password='password')
In Arch base distributions:
sudo pacman -S python-psycopg2
pip2 install psycopg2 # Use pip or pip3 to python3
On OSX 10.11.6 (El Capitan)
brew install postgresql
PATH=$PATH:/Library/PostgreSQL/9.4/bin pip install psycopg2
On OSX with macports:
sudo port install postgresql96
export PATH=/opt/local/lib/postgresql96/bin:$PATH
if pip is not working than you can download .whl file from here https://pypi.python.org/pypi/psycopg2
extract it..
than python setup.py install
I was having this problem, the main reason was with 2 equal versions installed. One by postgres.app and one by HomeBrew.
If you choose to keep only the APP:
brew unlink postgresql
pip3 install psycopg2
Installation on MacOS
Following are the steps, which worked for me and my team members while installing psycopg2 on Mac OS Big Sur and which we have extensively tested for Big Sur. Before starting make sure you have the Xcode command-line tool installed. If not, then install it from the Apple Developer site. The below steps assume you have homebrew installed. If you have not installed homebrew then install it. Last but not the least, it also assumes you already have PostgreSQL installed in your system, if not then install it. Different people have different preferences but the default installation method on the official PostgreSQL site via Enterprise DB installer is the best method for the majority of people.
Put up the linkage to pg_config file in your .zshrc file by: export PATH="$PATH:/Library/PostgreSQL/12/bin:$PATH". This way you are having linkage with the pg_config file in the /Library/PostgreSQL/12/bin folder. So if your PostgreSQL installation is via other means, like Postgres.app or Postgres installation via homebrew, then you need to have in your .zshrc file the link to pg_config file from the bin folder of that PostgreSQL installation as psycopg2 relies on that.
Install OpenSSL via Homebrew using the command brew install openssl. The reason for this is that libpq, the library which is the basis of psycopg2, uses openssl - psycopg2 doesn't use it directly. After installing put the following commands in your .zshrc file:
export PATH="/usr/local/opt/openssl#1.1/bin:$PATH"
export LDFLAGS="-L/usr/local/opt/openssl#1.1/lib"
export CPPFLAGS="-I/usr/local/opt/openssl#1.1/include"
By doing this you are creating necessary linkages in your directory. These commands are suggested by brew while you install openssl and have been directly picked up from there.
Now comes the most important step, which is to install libpq using the command brew install libpq. This installs libpq library. As per the documentation
libpq is the C application programmer's interface to PostgreSQL. libpq is a set of library functions that allow client programs to pass queries to the PostgreSQL backend server and to receive the results of these queries.
Link libpq using brew link libpq, if this doesn't work then use the command: brew link libpq --force.
Also put in your .zshrc file the following export PATH="/usr/local/opt/libpq/bin:$PATH". This creates all the necessary linkages for libpq library .
Now restart the terminal or use the following command source ~/.zshrc.
This works even when you are working in conda environment.
N.B. pip install psycopg2-binaryshould be avoided because as per the developers of the psycopg2 library
The use of the -binary packages in production is discouraged because in the past they proved unreliable in multithread environments. This might have been fixed in more recent versions but I have never managed to reproduce the failure.
I'm trying to install via pip some libraries but I'm having some problems.
When I try to install some of them I require for my project I get this message:
$ sudo pip install dj-database-url==0.2.0
Downloading/unpacking dj-database-url==0.2.0
Downloading dj-database-url-0.2.0.tar.gz
Cleaning up...
setuptools must be installed to install from a source distribution
It also happens when trying to install distribute==0.6.24
Any ideas?
Download ez_setup.py module from https://pypi.python.org/pypi/setuptools
Open a Terminal.
cd to the directory where you put the ez_setup.py.
Type python ez_setup.py and run it.
You should have it then.
After a pip install command I was getting the same error as you ("setuptools must be installed to install from a source distribution"). Since I couldn't find a solution, it was a lot faster to reinstall the virtual environment where python was running from.
If you're using virtualenvwrapper this is very easy. First you remove your problematic virtual environment (let's say it is called "venv") with:
rmvirtualenv venv
Then you setup a new one with the same name:
mkvirtualenv venv
And finally you install all your packages, including the one you had problems with:
pip install dj-database-url
I've created virtualenv for Python 2.7.4 on Ubuntu 13.04. I've installed python-dev.
I have the error when installing numpy in the virtualenv.
Maybe, you have any ideas to fix?
The problem is SystemError: Cannot compile 'Python.h'. Perhaps you need to install python-dev|python-devel.
so do the following in order to obtain 'Python.h'
make sure apt-get and gcc are up to date
sudo apt-get update
sudo apt-get upgrade gcc
then install the python2.7-dev
sudo apt-get install python2.7-dev
and I see that you have most probably already done the above things.
pip will eventually spit out another error for not being able to write into /user/bin/blahBlah/dist-packages/ or something like that because it couldn't figure out that it was supposed to install your desiredPackage (e.g. numpy) within the active env (the env created by virtualenv which you might have even changed directory to while doing all this)
so do this:
pip -E /some/path/env install desiredPackage
that should get the job done... hopefully :)
---Edit---
From PIP Version 1.1 onward, the command pip -E doesn't work. The following is an excerpt from the release notes of version 1.1 (https://pip.pypa.io/en/latest/news.html)
Removed -E/--environment option and PIP_RESPECT_VIRTUALENV; both use a restart-in-venv mechanism that's broken, and neither one is useful since every virtualenv now has pip inside it. Replace pip -E path/to/venv install Foo with virtualenv path/to/venv && path/to/venv/pip install Foo
If you're on Python3 you'll need to do sudo apt-get install python3-dev. Took me a little while to figure it out.
If you're hitting this issue even though you've installed all OS dependencies (python-devel, fortran compiler, etc), the issue might be instead related to the following bug:
"numpy installation thru install_requires directive issue..."
Work around is to manually install numpy in your (virtual) environment before running setup.py to install whatever you want to install that depends on numpy.
eg, pip install numpy then python ./setup.py install
This answer is for those of us that compiled python from source or installed it to a non standard directory. In my case, python2.7 was installed to /usr/local and the include files were installed to /usr/local/include/python2.7
C_INCLUDE_PATH=/usr/local/include/python2.7:$C_INCLUDE_PATH pip install numpy
I recently had the same problem. I run Debian Jessie and tried to install numpy from a Python 2.7.9 virtualenv. I got the same error -- numpy complaining that Python.h is missing while python2.7-dev and gcc are already installed.
File "numpy/core/setup.py", line 42, in check_types
],
File "numpy/core/setup.py", line 293, in check_types
SystemError: Cannot compile 'Python.h'. Perhaps you need to install python-dev|python-devel.
I'm running pip 1.5.6 and it doesn't appear to have command line option '-E'
$ pip -V
pip 1.5.6 from /home/alex/.virtualenvs/myenv/local/lib/python2.7/site- packages (python 2.7)
Upgrading pip to the latest verson 7.0.3 solves the problem
$ pip install --upgrade pip
Downloading/unpacking pip from https://pypi.python.org/packages/py2.py3/p/pip/pip-7.0.3-py2.py3-none-any.whl#md5=6950e1d775fea7ea50af690f72589dbd
Downloading pip-7.0.3-py2.py3-none-any.whl (1.1MB): 1.1MB downloaded
Installing collected packages: pip
Found existing installation: pip 1.5.6
Uninstalling pip:
Successfully uninstalled pip
Successfully installed pip
Cleaning up...
Now it is possible to install numpy
$ pip install numpy
Collecting numpy
Downloading numpy-1.9.2.tar.gz (4.0MB)
100% |████████████████████████████████| 4.0MB 61kB/s
Installing collected packages: numpy
Running setup.py install for numpy
Successfully installed numpy-1.9.2
This is probably because you do not have the python-dev package installed. You can install it like this:
sudo apt-get install python-dev
You can also install it via the Software Center:
#samkhan13 solution didn't work for me as pip said it doesn't have the -E option.
I was still getting the same error, but what worked for me was to install matplotlib, which installed numpy.