Question

So I have a bash script which outputs details on servers. The problem is that I need the output to be JSON. What is the best way to go about this? Here is the bash script:

# Get hostname
hostname=`hostname -A` 2> /dev/null

# Get distro
distro=`python -c 'import platform ; print platform.linux_distribution()[0] + " " +        platform.linux_distribution()[1]'` 2> /dev/null

# Get uptime
if [ -f "/proc/uptime" ]; then
uptime=`cat /proc/uptime`
uptime=${uptime%%.*}
seconds=$(( uptime%60 ))
minutes=$(( uptime/60%60 ))
hours=$(( uptime/60/60%24 ))
days=$(( uptime/60/60/24 ))
uptime="$days days, $hours hours, $minutes minutes, $seconds seconds"
else
uptime=""
fi

echo $hostname
echo $distro
echo $uptime

So the output I want is something like:

{"hostname":"server.domain.com", "distro":"CentOS 6.3", "uptime":"5 days, 22 hours, 1 minutes, 41 seconds"}

Thanks.

Answer 1

If you only need to output a small JSON, use printf:

printf '{"hostname":"%s","distro":"%s","uptime":"%s"}\n' "$hostname" "$distro" "$uptime"

Or if you need to produce a larger JSON, use a heredoc as explained by leandro-mora. If you use the here-doc solution, please be sure to upvote his answer:

cat <<EOF > /your/path/myjson.json
{"id" : "$my_id"}
EOF

---

Some of the more recent distros, have a file called: /etc/lsb-release or similar name (cat /etc/*release). Therefore, you could possibly do away with dependency your on Python:

distro=$(awk -F= 'END { print $2 }' /etc/lsb-release)

An aside, you should probably do away with using backticks. They’re a bit old fashioned.