How would I iterate through containers in the variable syntax?

Automation/IaC
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1

I am looking to get the internalip value from the containers list when using <%= instance.containers %> in bash script.

2

Don’t have an answer on dynamically iterating.

However, when using a fixed set of VMs in an instance I can use:

echo “<%=instance.containers[0].hostname%>: <%=instance.containers[0].internalIp%>: <%=instance.containers[0].externalIp%>”
echo “<%=instance.containers[1].hostname%>: <%=instance.containers[1].internalIp%>: <%=instance.containers[1].externalIp%>”

It works for me because I know exactly how many VMs are in each instance.

I could query the amount of VMs in an instance by using:

<%=instance.containers.size%>

However, when iterating it fails for me:

i=0
while [ $i -ne <%=instance.containers.size%> ]
do
i=$(($i+1))
echo “<%=instance.containers[$i].hostname%>: <%=instance.containers[$i].internalIp%>: <%=instance.containers[$i].externalIp%>”
done

When I comment out the line echo "<%=instance.containers[$i].hostname%>, it still fails. Making me wonder if the variable replacement gets done before invoking the script. I think there’s some Groovy behind it.

3

Variable replacement is done prior to script execution. It depends how you want to utilise the list of internal IPs. You could use the collect closure in groovy to return a list of internal ips for all containers:

echo "<%= instance.containers.collect{it.internalIp} %>"
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