Hosting pgAdmin4 with Apache/WSGI

Hi team,

Thanks for the hard work you've put in to develop pgAdmin4 and provide
support to the community. I'm writing to ask for your help to set up
pgAdmin4 in server mode under Apache with WSGI. I'm running Ubuntu 16.04
Server and installing pgAdmin4 version 1.6 with Python 2.7.12. A couple of
issues are getting in the way.

*Issue #1 Installation*

I struggled to install pgAdmin4 with the online documentation, being
unfamiliar with Python and WSGI. I followed the instructions on the
pgAdmin website but I was not getting the pgAdmin page on my browser.

I turned on debug logging in apache and was getting the following (details
redacted):

####
mod_wsgi (pid): Target WSGI script
'/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/pgAdmin4.wsgi'
cannot be loaded as Python module.
mod_wsgi (pid): Exception occurred processing WSGI script
'/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/pgAdmin4.wsgi'.
Traceback (most recent call last):
File
"/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/pgAdmin4.wsgi",
line 17, in <module>
import config
File
"/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/config.py",
line 24, in <module>
from pgadmin.utils import env, IS_PY2, IS_WIN, fs_short_path
File
"/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/pgadmin/__init__.py",
line 17, in <module>
from flask import Flask, abort, request, current_app, session
ImportError: No module named flask
####

But flask *was* installed in the virtual environment! I also ran setup.py
within the virtual environment. After hours of reading forum and mailing
list posts, scanning error logs, and trying things, I was able to get to
the pgAdmin4 landing page. As best I can tell, the issue was that I
installed pgAdmin4 in a virtual environment, under
/opt/pgadmin4/virtualenv, but apache2 wasn't using that virtual
environment. The solution was to add the following to pgAdmin4.wsgi right
before "import config":

activate_this = '/opt/pgadmin4/virtualenv/bin/activate_this.py'
execfile(activate_this, dict(__file__=activate_this))

Is this the right solution, or is there a better fix to this? Note that
the download instructions of the website recommend installing pgAdmin
inside a virtual environment (I had to learn what that was and how to set
it up), and the Server Setup instructions in the documentation don't
mention the need to add these lines.

If this is the right solution, it would help to clarify in the
documentation, and perhaps to add the hint to the error log. I'm including
this here hoping that others with the same problem will find this post and
it will save them hours of troubleshooting. A detailed walk-through in
the documentation would've been super helpful. If you'd like, I can share
my setup as a walk-through for posting on the website once I get it all
running well.

*Issue #2 Hosting within web subdirectory*

I want to host pgAdmin within a web subdirectory, e.g. example.com/pgadmin,
since the server has a website on root, e.g. example.com. I have the
following apache site configuration (details redacted):

<IfModule mod_ssl.c>
<VirtualHost _default_:443>
ServerName ***
ServerAdmin ***
DocumentRoot /var/www/html
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined

SSLEngine on
SSLCertificateFile ***
SSLCertificateKeyFile ***
SSLCACertificateFile ***

WSGIDaemonProcess pgadmin processes=1 threads=25
WSGIScriptAlias /pgadmin
/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4/pgAdmin4.wsgi

<Directory
/opt/pgadmin4/virtualenv/lib/python2.7/site-packages/pgadmin4>
WSGIProcessGroup pgadmin
WSGIApplicationGroup %{GLOBAL}
AllowOverride None
Require all granted
</Directory>
<Location "/pgadmin">
SSLVerifyClient require
SSLVerifyDepth 1
</Location>
</VirtualHost>
</IfModule>

This gets me the pgAdmin landing page, but nothing works. Clicking on "Add
New Server" does nothing. Clicking on "Configure pgAdmin" opens up a
dialog that says "Category is not selected." Nothing shows up in the
Browser.

If I change the apache config to host under / instead of under /pgadmin,
things do work. I see the "Servers" node in the browser, and the Create
Server dialog pops up when I click on "Add New Server". I am able to
connect to the database.

What configuration changes are necessary to get pgAdmin to work within a
subdirectory, e.g. /pgadmin?

*Issue #3 Using peer authentication*

Is there a way to use peer authentication without passwords? I had to
setup the connection without SSL and connecting to localhost, with a
password. I'm already protecting the landing page with client certificate
authentication, and pgAdmin itself requires password authentication, so I
figure another password isn't necessary. (Right?) The documentation says
"On Unix based systems, the address field may be left blank to use the
default PostgreSQL Unix Domain Socket on the local machine..." but pgAdmin
is requiring me to enter a host name in the connection tab or a host
address in the advanced tab.

Should I use SSL for traffic within the server (between the database and
the client) if I'm not sharing the server with anyone?

Any other configuration suggestions or tips are welcome.

Thanks in advance for your help.

Regards,
Gabriel