How to cache the downloaded packages of the apt-get in travis?

Question

I am using travis-ci to test my github repository and I found out that 3 to 10 minutes are spent on downloading deb packages. They are only 127 MB big.

I checked travis-ci/Caching Dependencies and Directories but there is no support for apt-get.

How to do this?

Answer 1

It is possible to achieve this by caching the content in another folder that is accessible for non-root users, and mv all deb under it into /var/cache/apt/archives/. After installation, cp them back to that folder.

Note:

I recommand you to make YOUR_DIR_FOR_DEB_PACKAGES somewhere under ~.

# .travis.yml

sudo: required

cache:
  - directories:
    - $YOUR_DIR_FOR_DEB_PACKAGES # This must be accessible for non-root users

addons:
  apt:
    sources:
      # Whatever source you need

# Download the dependencies if it is not cached
# All the "echo" and "ls" in "before_script" can be remove since they are only used for debugging.
before_script:
  - echo "Print content of $YOUR_DIR_FOR_DEB_PACKAGES"
  - ls $YOUR_DIR_FOR_DEB_PACKAGES
  - echo "Check whether apt-get has no cache"
  - ls /var/cache/apt/archives
  -
  - echo "Start loading cache"
  - |
    exist() {
        [ -e "$1" ]
    }
  - |
    if exist ~/$YOUR_DIR_FOR_DEB_PACKAGES/*.deb
    then
        sudo mv ~/$YOUR_DIR_FOR_DEB_PACKAGES/*.deb /var/cache/apt/archives/
        ls /var/cache/apt/archives
    fi
  -
  - echo "Start to install software"
  - sudo apt-get update
  - sudo apt-get install -y --no-install-recommends --no-install-suggests $THE_PACKAGES_REQUIRED
  -
  - echo "Start updating the cache"
  - cp /var/cache/apt/archives/*deb ~/$YOUR_DIR_FOR_DEB_PACKAGES/

script:
  - # Do whatever you want here.