Example: Install tools¶
Application images are designed to be as lightweight as possible, and as such, common tools you might expect to see in a regular cloud image might not be available.
You can use hooks to install packages that you require for your application. In this example, we’ll install curl
and python3
.
To do so, create a new addon with the following pre-start
hook:
#!/bin/bash -e
# We only need to install things once when the image is being created, so we
# don't need to execute the hook when users are running the application.
if [ "$INSTANCE_TYPE" = "regular" ]; then
exit 0
fi
apt update -q
apt install -y curl python3
When an application is created or updated with this addon, both curl
and python3
will be installed and made available for other hooks to use.