Openstack Heat : Installing Applications along with the heat template

Installing Applications along with the heat template. If needed we can mention the network ID, Image ID etc in the file itself instead of asking it from outside.
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heat_template_version: 2013-05-23

description: Test Template

parameters:
NAME:
type: string
description : Instance Name
ImageID:
type: string
description: Image use to boot a server
NetID:
type: string
description: Network ID for the server

resources:
server1:
type: OS::Nova::Server
properties:
name: { get_param: NAME }
image: { get_param: ImageID }
key_name: Cloud
flavor: "m1.small"
networks:
- network: { get_param: NetID }
user_data_format: RAW
user_data: |
#!/bin/bash -v
echo "nameserver 8.8.8.8" > /etc/resolv.conf
yum update -y
yum install httpd -y

outputs:
server1_private_ip:
description: IP address of the server in the private network
value: { get_attr: [ server1, first_address ] }
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heat stack-create -f heat.yml -P "ImageID=abc9818d-ee5f-4778-ada5-a29105ea9c02;NetID=71ed8a34-a2d5-4d84-9d47-e5e107dd8d7e" Centos-Stack