How to list/download the recursive dependencies of a debian package?

Question

I need to list/download all the recursive dependencies of a debian package.

Suppose i need to install package a.deb and it depends on package b.deb and again package b.d

Answer 1

As midihenry pointed out - install the apt-rdepends package and then run this

$ apt-rdepends gcc | awk '$1 ~ /^Depends:/{print $2}' | xargs apt-get download

this line will get all dependencies recursively and, looking at the second pipe, will download all the packages by name from the stdio, which is what the line -

awk $1 ~ /^Depends:/{print $2} does. prints out the names of packages. If you run these commands additively, you'll see what i mean.

Answer 2

You can use apt-rdepends for getting all the dependencies for a package recursively. And by piping the result to grep you can have only the package names and omit unneeded information.

Example:

 $ apt-rdepends cowsay | grep -E '^[a-zA-Z0-9]'

Output:

cowsay
perl
libbz2-1.0
libc6
libgcc1
gcc-4.9-base
multiarch-support
libdb5.3
libgdbm3
dpkg
liblzma5
libselinux1
libpcre3
tar
libacl1
libattr1
zlib1g
install-info
perl-base
perl-modules

You can then download those packages using apt-get download $package and install them offline on your machine.

By default, apt installs Recommends, so you might want to run apt-rdepends like so:

apt-rdepends -f Depends,PreDepends,Recommends -s Depends,PreDepends,Recommends cowsay

Since apt-rdepends by default follows and shows only Depends, PreDepends.

Answer 3

For some reason apt-rdepends did not work for me (when searching the 'docker-engine' package, it missed the dependency onto libltdl7 which was introduced with docker-engine 1.11.1-0). UPD Supposedly owing to the fact that apt-rdepends doesn't follow and doesn't list Recommends by default. And doesn't follow virtual packages.

So I came up with following command suite.

Recursively list dependencies

$ apt-cache depends --recurse --no-recommends --no-suggests --no-conflicts --no-breaks --no-replaces --no-enhances <your-package-here> | grep "^\w" | sort -u

(you obviously have to change <your-package-here> at the end of the line with the package you want to analyze)

The key here is the --recurse option. Unfortunately, you cannot specify the content you want (or I did not find the way) so you need to turn off all unwanted dependencies to keep only "dependencies". It is a bit verbose and hard to remember!

From the apt-cache man page:

Per default the depends and rdepends print all dependencies

Download those dependencies

So in order to download those dependencies, run following command which will download them into the current working directory:

$ apt-get download $(apt-cache depends --recurse --no-recommends --no-suggests --no-conflicts --no-breaks --no-replaces --no-enhances <your-package-here> | grep "^\w" | sort -u)

Optionally, to install those dependencies

This extends slightly the asked question, but it seems to match the intent of the question.

You need to build the index of the just downloaded packages. This is done from the same folder where all .deb where downloaded:

$ dpkg-scanpackages . | gzip -9c > Packages.gz

Then just copy that folder (all .deb + the Packages.gz file) to the target system which does not have Internet access and add the folder to the APT source list.

$ echo "deb file:<your folder here> ./" | sudo tee -a /etc/apt/sources.list
$ sudo apt-get update

Et voilà

On a system w/o Internet access, I can install a package (Docker in my example) and its dependencies:

$ sudo apt-get install docker-engine