How can I check if a package is installed and install it if not?
BashApt GetBash Problem Overview
I'm working on a Ubuntu system and currently this is what I'm doing:
if ! which command > /dev/null; then
echo -e "Command not found! Install? (y/n) \c"
read
if "$REPLY" = "y"; then
sudo apt-get install command
fi
fi
Is this what most people would do? Or is there a more elegant solution?
Bash Solutions
Solution 1 - Bash
To check if packagename was installed, type:
dpkg -s <packagename>
You can also use dpkg-query that has a neater output for your purpose, and accepts wild cards, too.
dpkg-query -l <packagename>
To find what package owns the command, try:
dpkg -S `which <command>`
For further details, see article Find out if package is installed in Linux and dpkg cheat sheet.
Solution 2 - Bash
To be a little more explicit, here's a bit of Bash script that checks for a package and installs it if required. Of course, you can do other things upon finding that the package is missing, such as simply exiting with an error code.
REQUIRED_PKG="some-package"
PKG_OK=$(dpkg-query -W --showformat='${Status}\n' $REQUIRED_PKG|grep "install ok installed")
echo Checking for $REQUIRED_PKG: $PKG_OK
if [ "" = "$PKG_OK" ]; then
echo "No $REQUIRED_PKG. Setting up $REQUIRED_PKG."
sudo apt-get --yes install $REQUIRED_PKG
fi
If the script runs within a GUI (e.g., it is a Nautilus script), you'll probably want to replace the 'sudo' invocation with a 'gksudo' one.
Solution 3 - Bash
This one-liner returns 1 (installed) or 0 (not installed) for the 'nano' package...
$(dpkg-query -W -f='${Status}' nano 2>/dev/null | grep -c "ok installed")
even if the package does not exist or is not available.
The example below installs the 'nano' package if it is not installed...
if [ $(dpkg-query -W -f='${Status}' nano 2>/dev/null | grep -c "ok installed") -eq 0 ];
then
apt-get install nano;
fi
Solution 4 - Bash
dpkg-query --showformat='${db:Status-Status}'
This produces a small output string which is unlikely to change and is easy to compare deterministically without grep:
pkg=hello
status="$(dpkg-query -W --showformat='${db:Status-Status}' "$pkg" 2>&1)"
if [ ! $? = 0 ] || [ ! "$status" = installed ]; then
sudo apt install $pkg
fi
The $? = 0 check is needed because if you've never installed a package before, and after you remove certain packages such as hello, dpkg-query exits with status 1 and outputs to stderr:
dpkg-query: no packages found matching hello
instead of outputting not-installed. The 2>&1 captures that error message too when it comes preventing it from going to the terminal.
For multiple packages:
pkgs='hello certbot'
install=false
for pkg in $pkgs; do
status="$(dpkg-query -W --showformat='${db:Status-Status}' "$pkg" 2>&1)"
if [ ! $? = 0 ] || [ ! "$status" = installed ]; then
install=true
break
fi
done
if "$install"; then
sudo apt install $pkgs
fi
The possible statuses are documented in man dpkg-query as:
n = Not-installed
c = Config-files
H = Half-installed
U = Unpacked
F = Half-configured
W = Triggers-awaiting
t = Triggers-pending
i = Installed
The single letter versions are obtainable with db:Status-Abbrev, but they come together with the action and error status, so you get 3 characters and would need to cut it.
So I think it is reliable enough to rely on the uncapitalized statuses (Config-files vs config-files) not changing instead.
dpkg -s exit status
This unfortunately doesn't do what most users want:
pkgs='qemu-user pandoc'
if ! dpkg -s $pkgs >/dev/null 2>&1; then
sudo apt-get install $pkgs
fi
because for some packages, e.g. certbot, doing:
sudo apt install certbot
sudo apt remove certbot
leaves certbot in state config-files, which means that config files were left in the machine. And in that state, dpkg -s still returns 0, because the package metadata is still kept around so that those config files can be handled more nicely.
To actually make dpkg -s return 1 as desired, --purge would be needed:
sudo apt remove --purge certbot
which actually moves it into not-installed/dpkg-query: no packages found matching.
Note that only certain packages leave config files behind. A simpler package like hello goes directly from installed to not-installed without --purge.
Tested on Ubuntu 20.10.
Python apt package
There is a pre-installed Python 3 package called apt in Ubuntu 18.04 which exposes an Python apt interface!
A script that checks if a package is installed and installs it if not can be seen at: https://stackoverflow.com/questions/17537390/how-to-install-a-package-using-the-python-apt-api/17538002#17538002
Here is a copy for reference:
#!/usr/bin/env python
# aptinstall.py
import apt
import sys
pkg_name = "libjs-yui-doc"
cache = apt.cache.Cache()
cache.update()
cache.open()
pkg = cache[pkg_name]
if pkg.is_installed:
print "{pkg_name} already installed".format(pkg_name=pkg_name)
else:
pkg.mark_install()
try:
cache.commit()
except Exception, arg:
print >> sys.stderr, "Sorry, package installation failed [{err}]".format(err=str(arg))
Check if an executable is in PATH instead
See also
Solution 5 - Bash
Ubuntu added its "Personal Package Archive" (PPA), and PPA packages have a different result.
-
A native Debian repository package is not installed:
~$ dpkg-query -l apache-perl ~$ echo $? 1 -
A PPA package registered on the host and installed:
~$ dpkg-query -l libreoffice ~$ echo $? 0 -
A PPA package registered on the host, but not installed:
~$ dpkg-query -l domy-ce ~$ echo $? 0 ~$ sudo apt-get remove domy-ce [sudo] password for user: Reading package lists... Done Building dependency tree Reading state information... Done Package domy-ce is not installed, so not removed 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Also posted on: Test if a package is installed in APT
Solution 6 - Bash
> However you can't simply rely on return codes here for scripting
In my experience you can rely on dkpg's exit codes.
The return code of dpkg -s is 0 if the package is installed and 1 if it's not, so the simplest solution I found was:
dpkg -s <pkg-name> 2>/dev/null >/dev/null || sudo apt-get -y install <pkg-name>
It works fine for me...
Solution 7 - Bash
This seems to work pretty well.
$ sudo dpkg-query -l | grep <some_package_name> | wc -l
- It either returns
0if not installed or some number> 0if installed.
Solution 8 - Bash
I've settled on one based on Nultyi's answer:
MISSING=$(dpkg --get-selections $PACKAGES 2>&1 | grep -v 'install$' | awk '{ print $6 }')
# Optional check here to skip bothering with apt-get if $MISSING is empty
sudo apt-get install $MISSING
Basically, the error message from dpkg --get-selections is far easier to parse than most of the others, because it doesn't include statuses like "deinstall". It also can check multiple packages simultaneously, something you can't do with just error codes.
Explanation/example:
$ dpkg --get-selections python3-venv python3-dev screen build-essential jq
dpkg: no packages found matching python3-venv
dpkg: no packages found matching python3-dev
screen install
build-essential install
dpkg: no packages found matching jq
So grep removes installed packages from the list, and awk pulls the package names out from the error message, resulting in MISSING='python3-venv python3-dev jq', which can be trivially inserted into an install command.
I'm not blindly issuing an apt-get install $PACKAGES, because as mentioned in the comments, this can unexpectedly upgrade packages you weren't planning on; not really a good idea for automated processes that are expected to be stable.
Solution 9 - Bash
It seems that nowadays apt-get has an option --no-upgrade that just does what the OP wants:
> --no-upgrade Do not upgrade packages. When used in conjunction with install, no-upgrade will prevent packages listed from being upgraded if they are already installed.
Manpage from https://linux.die.net/man/8/apt-get
Therefore you can use
apt-get install --no-upgrade package
and package will be installed only if it's not.
Solution 10 - Bash
This will do it. apt-get install is idempotent.
sudo apt-get install --no-upgrade command
Solution 11 - Bash
I've found all solutions in previous answers can produce a false positive if a package is installed and then removed, yet the installation package remains on the system.
To replicate:
Install package apt-get install curl
Remove package apt-get remove curl
Now test the previous answers.
The following command seems to solve this condition:
dpkg-query -W -f='${Status}\n' curl | head -n1 | awk '{print $3;}' | grep -q '^installed$'
This will result in a definitive installed or not-installed.
Solution 12 - Bash
$name="rsync"
[ `which $name` ] $$ echo "$name : installed" || sudo apt-get install -y $name
Solution 13 - Bash
Use:
apt-cache policy <package_name>
If it is not installed, it will show:
Installed: none
Otherwise it will show:
Installed: version
Solution 14 - Bash
Inspired by Chris' answer:
#! /bin/bash
installed() {
return $(dpkg-query -W -f '${Status}\n' "${1}" 2>&1|awk '/ok installed/{print 0;exit}{print 1}')
}
pkgs=(libgl1-mesa-dev xorg-dev vulkan-tools libvulkan-dev vulkan-validationlayers-dev spirv-tools)
missing_pkgs=""
for pkg in ${pkgs[@]}; do
if ! $(installed $pkg) ; then
missing_pkgs+=" $pkg"
fi
done
if [ ! -z "$missing_pkgs" ]; then
cmd="sudo apt install -y $missing_pkgs"
echo $cmd
fi
Solution 15 - Bash
This feature already exists in Ubuntu and Debian, in the command-not-found package.
Solution 16 - Bash
This command is the most memorable:
dpkg --get-selections <package-name>
If it's installed it prints:
> <package-name> install
Otherwise it prints
> No packages found matching <package-name>.
This was tested on Ubuntu 12.04.1 (Precise Pangolin).
Solution 17 - Bash
which <command>
if [ $? == 1 ]; then
<pkg-manager> -y install <command>
fi
Solution 18 - Bash
apt list [packagename]
seems to be the simplest way to do it outside of dpkg and older apt-* tools.
Solution 19 - Bash
For Ubuntu, apt provides a fairly decent way to do this. Below is an example for Google Chrome:
apt -qq list google-chrome-stable 2>/dev/null | grep -qE "(installed|upgradeable)" || apt-get install google-chrome-stable
I'm redirecting error output to null, because apt warns against using its "unstable cli". I suspect list package is stable, so I think it's ok to throw this warning away. The -qq makes apt super quiet.
Solution 20 - Bash
I had a similar requirement when running test locally instead of in Docker. Basically I only wanted to install any .deb files found if they weren't already installed.
# If there are .deb files in the folder, then install them
if [ `ls -1 *.deb 2> /dev/null | wc -l` -gt 0 ]; then
for file in *.deb; do
# Only install if not already installed (non-zero exit code)
dpkg -I ${file} | grep Package: | sed -r 's/ Package:\s+(.*)/\1/g' | xargs dpkg -s
if [ $? != 0 ]; then
dpkg -i ${file}
fi;
done;
else
err "No .deb files found in '$PWD'"
fi
I guess the only problem I can see is that it doesn't check the version number of the package so if .deb file is a newer version. Then this wouldn't overwrite the currently installed package.
Solution 21 - Bash
This explicitly prints 0 if installed else 1 using only awk:
dpkg-query -W -f '${Status}\n' 'PKG' 2>&1|awk '/ok installed/{print 0;exit}{print 1}'
or if you prefer the other way around where 1 means installed and 0 otherwise:
dpkg-query -W -f '${Status}\n' 'PKG' 2>&1|awk '/ok installed/{print 1;exit}{print 0}'
** replace PKG with your package name
Convenience function:
installed() {
return $(dpkg-query -W -f '${Status}\n' "${1}" 2>&1|awk '/ok installed/{print 0;exit}{print 1}')
}
# usage:
installed gcc && echo Yes || echo No
#or
if installed gcc; then
echo yes
else
echo no
fi
Solution 22 - Bash
Kinda based off yours just a little more 'elegant'. Just because I'm bored.
#!/bin/bash
FOUND=("\033[38;5;10m")
NOTFOUND=("\033[38;5;9m")
PKG="${@:1}"
command ${PKG} &>/dev/null
if [[ $? != 0 ]]; then
echo -e "${NOTFOUND}[!] ${PKG} not found [!]"
echo -e "${NOTFOUND}[!] Would you like to install ${PKG} now ? [!]"
read -p "[Y/N] >$ " ANSWER
if [[ ${ANSWER} == [yY] || ${ANSWER} == [yY][eE][sS] ]]; then
if grep -q "bian" /etc/os-release; then
sudo apt-get install ${PKG}
elif grep -q "arch" /etc/os-release; then
if [[ -f /bin/yay ]] || [[ -f /bin/yaourt ]]; then
yaourt -S ${PKG} 2>./err || yay -S ${PKG} 2>./err
else
sudo pacman -S ${PKG}
fi
elif grep -q "fedora" /etc/os-release; then
sudo dnf install ${PKG}
else
echo -e "${NOTFOUND}[!] This script couldn't detect your package manager [!]"
echo -e "${NOTFOUND}[!] Manually install it [!]"
fi
elif [[ ${ANSWER} == [nN] || ${ANSWER} == [nN][oO] ]]; then
echo -e "${NOTFOUND}[!] Exiting [!]"
fi
else
echo -e "${FOUND}[+] ${PKG} found [+]"
fi
Solution 23 - Bash
The answers that suggest to use something along the lines of:
dpkg-query --showformat '${db:Status-Status}\n' --show $package | grep -q '^installed$'
dpkg-query --showformat '${Status}\n' --show $package | grep -q '^install ok installed$'
are correct.
But if you have the package dpkg-dev installed and you do not just want to check whether a package is installed but you also:
- want to know whether a package is installed in a certain version
- want to have a package in a certain architecture
- want to see if a virtual package is provided
then you can abuse the dpkg-checkbuilddeps tool for this job:
dpkg-checkbuilddeps -d apt /dev/null
This will check whether apt is installed.
The following will check whether apt is installed in at least version 2.3.15 and grep is installed as amd64 and the virtual package x-window-manager is provided by some of the installed packages:
dpkg-checkbuilddeps -d 'apt (>= 2.3.15), grep:amd64, x-window-manager' /dev/null
The exit status of dpkg-checkbuilddeps will tell the script whether the dependencies are satisfied or not. Since this method supports passing multiple packages, you only have to run dpkg-checkbuilddeps once even if you want to check whether more than one package is installed.
Solution 24 - Bash
Since you mentioned Ubuntu, and you want to do this programmatically(although dpkg variations can also be used but would be more complex to implement), this(which) will definitely work:
#!/bin/bash
pkgname=mutt
which $pkgname > /dev/null;isPackage=$?
if [ $isPackage != 0 ];then
echo "$pkgname not installed"
sleep 1
read -r -p "${1:-$pkgname will be installed. Are you sure? [y/N]} " response
case "$response" in
[yY][eE][sS]|[yY])
sudo apt-get install $pkgname
;;
*)
false
;;
esac
else
echo "$pkgname is installed"
sleep 1
fi
Although for POSIX compatibility, you would want to use command -v instead as mentioned in another similar question.
In that case,
which $pkgname > /dev/null should be replaced by command -v $pkgname in the above code sample.
Solution 25 - Bash
I use the following way:
which mySQL 2>&1|tee 1> /dev/null
if [[ "$?" == 0 ]]; then
echo -e "\e[42m MySQL already installed. Moving on...\e[0m"
else
sudo apt-get install -y mysql-server
if [[ "$?" == 0 ]]; then
echo -e "\e[42mMy SQL installed\e[0m"
else
echo -e "\e[42Installation failed\e[0m"
fi
fi
Solution 26 - Bash
I use this solution as I find it most straightforward.
function must_install(){
return "$(apt -qq list $var --installed 2> /dev/null |wc -l)"
}
function install_if() {
unset install
for var in "$@"
do
if $(must_install $var)
then
install+="${var} "
fi
done
if [ -n "$install" ];
then
sudo apt-get install -qy $install
fi
}
The neat thing is, must_install returns 1 or 0 which is then interpreted as true or false from the calling if, so we don't need any test using [].
install_if takes any number of packages separated by space.
The problem is apt is not meant to be used in scripts, so this might stop working at any time. 8)