Groovy : multiple loops in template engine using GStringTemplateEngine() - groovy

Question

This question is in continuation with earlier question I have posted before.
To enhance my templates further I need to have multiple loops in the template engines and the values need to be replaced from the HashMap Variables that were derived from a configuration file.
My HashMap looks something like this, let say envVar:
envVar = [
PROJECT:name,
env:[
[name:param1, value:value1],
[name:param2, value:value2],
[name:param3, value:value3]],
ports:[
[protocol:port1, port:1000],
[protocol:port2, port:2000]]
]
My template engine looks like this:
- env:
<< NEED TO LOOP HERE WITH env variables
- name : param1
value : value1
....
>>
project: "${PROJECT}"
......
......
......
ports:
<< NEED TO LOOP HERE WITH ports variables
- port: 1000
protocol : port1
....
>>
Code snippet is described below.
def f = new File('output.template')
def engine = new groovy.text.GStringTemplateEngine()
//....
//envVar are derived from another file
//....
def Template = engine.createTemplate(f).make(envVar)
println "${Template}"
Can someone explain me how to modify the above code snippet and templates to make sure the envVar will be replaced properly in the template engine.

Answer 1

You need to do an each for every variable. Your template file needs to look like this:
#cat output.template
- env:<% env.each { v -> %>
- name : ${v.name}
value : ${v.value}<% } %>
project: "${PROJECT}"
......
......
......
ports:<% ports.each { v -> %>
- port: ${v.port}
protocol: ${v.protocol}<% } %>
Then, your main script should look like this:
def f = new File('output.template')
def engine = new groovy.text.GStringTemplateEngine()
def envVar = [
PROJECT: name,
env:[
[name:'param1', value:'value1'],
[name:'param2', value:'value2'],
[name:'param3', value:'value3']
],
ports:[
[protocol:'port1', port:1000],
[protocol:'port2', port:2000]
]
]
def Template = engine.createTemplate(f).make(envVar)
println "${Template}".trim()
output:
#cat output.template
- env:
- name : param1
value : value1
- name : param2
value : value2
- name : param3
value : value3
project: "projectName"
......
......
......
ports:
- port: 1000
protocol: port1
- port: 2000
protocol: port2

Answer 2

to navigate through your env variable you can use the following:
envVar.env.each{
println "name : ${it.name}"
println "value : ${it.value}"
}
envVar.ports.each{
println "port : ${it.port}"
println "protocol : ${it.protocol}"
}