Sander van Dragt

I run my own Nextcloud server, and every other week there's an update to the server, or one of the plugins I've enabled. The following steps enable automatic updates to the Nextcloud server.

This assumes Nextcloud is installed under /var/www/nextcloud:

Add a scheduled task as the webserver user:

$ sudo -u www-data crontab -e

Add the following line to run the upgrade script once a day at 4:05am. Instead of running the upgrade process directly we run a script so that we can also run it from the shell if needed:

5     4  *  *  * cd /var/www/nextcloud && ./upgrade.sh

Now create the script and make it executable:

$ cd /var/www/nextcloud
$ nano upgrade.sh && sudo chmod +x upgrade.sh

The script itself runs the server updater, the no-interaction argument prevents prompting for questions, followed by the occ utility to update all installed apps.

  pushd $(dirname $0)/updater
        /usr/bin/php updater.phar --no-interaction
        cd ..; ./occ app:update --all
  popd

#linux #nextcloud

Today I managed to break pipenv again to a point where I cannot install any project requirements. Let's document the process to prevent this happening again in the future.

Python3.7 and pip are already installed on OpenSUSE Tumbleweed. If you're not so lucky, read the page on https://docs.python-guide.org/starting/install3/linux/ but stop at the bottom of the page, as I find the installation method used for pipenv there too brittle.

Instead we're going to install pipx which is best described as a per-command environment for python executables. This is great for packages like pipenv which can then run without conflicts. pipx also keeps the packages updated.

python3 -m pip install --user pipx
python3 -m pipx ensurepath

We can then use pipx to install pipenv:

pipx install pipenv

I prefer to keep the virtual environment within the project folder, by adding the following line to .bashrc or .zshrc:

export PIPENV_VENV_IN_PROJECT=1

With pipenv in place we can create a per-project virtual environment and activate it:

cd ~/dev/myproject
pipenv shell

We can install our packages into the environment now:

pipenv install pylint --dev
pipenv install black --dev --pre

The missing step in a lot of guides, is that you later might want to call your script from outwith your virtual environment, without explicitly activating it as you would do when working on the project itself. You can do that thusly:

$(pipenv --venv)/bin/python myscript.py


#python

If when trying to start a vm, for example using vagrant, you get the error message that the host network adapter cannot be created:

There was an error while executing `VBoxManage`, a CLI used by Vagrant
for controlling VirtualBox. The command and stderr is shown below.

Command: ["hostonlyif", "create"]

Stderr: 0%...
Progress state: NS_ERROR_FAILURE
VBoxManage: error: Failed to create the host-only adapter
VBoxManage: error: VBoxNetAdpCtl: Error while adding new interface: failed to open /dev/vboxnetctl: No such file or directory
VBoxManage: error: Details: code NS_ERROR_FAILURE (0x80004005), component HostNetworkInterfaceWrap, interface IHostNetworkInterface
VBoxManage: error: Context: "RTEXITCODE handleCreate(HandlerArg*)" at line 94 of file VBoxManageHostonly.cpp

Make sure to first start the virtualbox GUI application. It does some extra checks, and sometimes highlights the permission problem:

In my case (OpenSuse 15.1 Leap), my user was not added to the vboxusers group. Via Yast > Users and Security .... and editing my user account it was a simple checkbox away. Remember to relog.

If that doesn't work, reloading the kernel extensions could help:

$ sudo dpkg-reconfigure virtualbox-dkms
$ sudo dpkg-reconfigure virtualbox
$ sudo modprobe vboxdrv 
$ sudo modprobe vboxnetadp

#opensuse #virtualbox #linux #vagrant

I was looking for a tea timer countdown but quickly realised I might as well use a countdown script for this. I based my script on the linked script but added a customizable notification at the end

$ nano ~/bin/countdown

#!/bin/bash
# v2 - 2019-05-01
secs=$1
msg=${2:-$1 seconds passed.}
while [ $secs -gt 0 ]; do
   echo -ne "$secs\033[0K\r"
   sleep 1
   : $((secs--))
done
notify-send 'Countdown Finished' "$msg"

$ chmod +x ~/bin/countdown
$ countdown 180 "Tea is ready."

#linux

On Linux operating systems, Spotify does not always show the file and view menus. This makes it harder to hide the "Find Friends" bar as there is no close button on the sidebar itself.

However there's another way: Click on the chevron in the top right corner next to your spotify username, then on Settings > Display Options > untick Show Friend Activity.

#linux #howto

After another hour of resolving issues with pyenv and a personal project that requires Python 3.7 I thought it best to note the steps I used to install Python 3.7.1 on OpenSUSE Tumbleweed:

# Install requirements for compiling Python
sudo zypper in zlib-devel bzip2 libbz2-devel libffi-devel libopenssl-devel readline-devel sqlite3 sqlite3-devel xz xz-devel 

# Compile Python
cd ~/Downloads
wget https://www.python.org/ftp/python/3.7.1/Python-3.7.1.tar.xz
tar xf Python-3.7.1.tar.xz
cd Python-3.7.1
./configure
make

# AltInstall ensures 3.7.1 is installed alongside your system python
sudo make altinstall

# Fix dynamic library loading
sudo ln -s /usr/local/lib64/python3.7/lib-dynload /usr/local/lib/python3.7/lib-dynload

I've updated the Common build problems · pyenv/pyenv Wiki page to reflect the updated required packages. Thanks to Andrew Cooke for the dynamic library fix

#python #linux

Linux is so userfriendly, so the rpm that can be downloaded is missing dependencies. However, I'm quickly becoming a fan of zypper and OpenSUSE's dependency handling, and comes to the rescue:

sudo zypper in cryptomator.rpm

Even though cryptomator made a mistake in signing part of the application, it can still be installed by pressing ignore. Are you sure you want to do that? It seems a bit crap for such an essential utility.

#linux

Both the official RPM and the discover package failed for me due to missing dependencies, without specifying what those are. However the following worked:

sudo zypper install dropbox-cli
dropbox start -i
dropbox autostart

#linux

Having wasted too much time installing Ubuntu on a laptop recently, I thought it would be helpful for the future self to document the issues.

Issues

sudo su
apt install cifs-utils
echo "//path/to/windows-share /mnt/team cifs credentials=/etc/samba/credentials,uid=1000 0 0" >> /etc/stab
cat > /etc/samba/credentials <<EOC
username=UserName
password=PassWord
EOC
chown root.root /etc/samba/credentials && chmod 400 /etc/samba/credentials

This document will get updated as I stumble and fix other issues.

App Alternatives

#linux

I've been finding that browsing has been slow for me lately on my linux box, which has Ubuntu 16.04 installed. After some investigation it seemed worthwhile to try to install a DNS cache to speed up DNS queries. This has sped up successive DNS queries from 21ms to 0ms, removing sluggishness.

sudo apt install bind9
cd /etc/resolvconf/resolv.conf.d
sudo echo "nameserver 127.0.0.1" >> head

Apply the configuration as follows:

sudo resolvconf -u

The improvement can be seen by using dig to query a domain and looking at the Query time output. After the first dig, subsequent digs return in 0 ms.

#linux

Ubuntu 17.10 comes with python3 3.6.3 installed by default but not pip and pipenv. We can install install pip systemwide and pipenv into the user local bin so we can use all the convenience when working with our python projects:

wget https://bootstrap.pypa.io/get-pip.py -O /tmp/get-pip.py
sudo python3 /tmp/get-pip.py
pip3 install --user pipenv
echo "PATH=$HOME/.local/bin:$PATH" >> ~/.profile
source ~/.profile

Sources: Installing Python 3 on Linux; pip installation; Installing pipenv; How to permanently set PATH on Linux

Update 9 Nov 2017: replaced curl with wget, thanks Peter

#python #technology

Today a problem came up where the files on my Samba fileshare did not indicate to my Windows system that they were changed. Software that relies on this information such as TortoiseHG and SimpleLESS would not know that the file had changed. This was especially obvious with SimpleLESS which should take the .less file and process it, but wouldn’t.

#link #linux

I recently set up a local development server running Ubuntu on VMware player. I thought it would be interesting to document the process and instructions so that it will be useful to others, and you can follow along / correct / improve this guide. On completion of this series you will end up with a complete LAMP local development system..

username: __________ password: __________ 

#linux

Once you understand Linux file permissions, the next step on the road to enlightenment is learning how to check the permissions for a file or directory.

via http://articles.slicehost.com/2010/7/17/checking-linux-file-permissions-with-ls&hl=en&strip=...">Slicehost Articles: Checking Linux file permissions with ls

#linux

Linux file permissions are strange and wondrous things. Start down the path of understanding by looking at the core concepts behind them before moving on to practical applications.

via Slicehost Articles: Linux file permission concepts

#linux