How to find ami id using shell script - shell

Question

How to find ami id using shell script
My Script :
for i in $(cat /tmp/amidel.txt); do
echo "Image ID of instance which needed to be Deregistered is $i ";
val1="$i"-i-*
aws ec2 describe-images --filters "Name=name,Values=$val1" | awk '{ print $11 }'
done
Now Issue is that "aws ec2 describe-images" returns image id for different awk value :
$ aws ec2 describe-images --filters "Name=name,Values=instance-20Aug15-i-*" | awk '{ print $9 }'
Output :
ami-xxxx
$ aws ec2 describe-images --filters "Name=name,Values=instance-18Aug15-i-*" | awk '{ print $11 }'
Output :
ami-xxxx
This is happening because third value returned by "aws ec2 describe-images" is Comment which varies for each ami image :
$ aws ec2 describe-images --filters "Name=name,Values=instance-18Aug15-i-*"
Output :
IMAGES x86_64 This is for Daily auto AMI creation xen ami-bebfb1ec 008392659736/instance-18Aug15-i-1effb6d3 machine aki-503e7402 instance-18Aug15-i-1effb6d3 008392659736 False /dev/sda1 ebs available paravirtual
BLOCKDEVICEMAPPINGS /dev/sda1
EBS True snap-51539764 8 gp2
BLOCKDEVICEMAPPINGS /dev/sdf
EBS False snap-4e95d37b 20 gp2
For 2nd Ami :
$ aws ec2 describe-images --filters "Name=name,Values=instance-20Aug15-i-*"
Output :
IMAGES x86_64 This is created by ami-backup.sh xen ami-52020b00 008392659736/instance-20Aug15-i-127fb8df machine instance-20Aug15-i-127fb8df 008392659736 False /dev/sda1 ebs simple available hvm
BLOCKDEVICEMAPPINGS /dev/sda1
EBS True snap-2b563aca 8 gp2
So please help me how parse this to get proper ami id or is there any other method to find ami id from ami name ?

Answer 1

awk is an inappropriate tool to parse JSON. jq would be substantially more appropriate if you like chaining tools.
You can change the output format returned by aws-cli. That makes awk/grep more appropriate.
You can also use --query instead of trying to parse it through awk. It uses the JMESPath syntax, which is slightly easier than the jq syntax.
Here's some examples:
$ aws ec2 describe-images --image-ids ami-6b1cd400 --query Images[].ImageId
[
"ami-6b1cd400"
]
$ aws ec2 describe-images --image-ids ami-6b1cd400 --query Images[].ImageId --output text
ami-6b1cd400

Answer 2

We can find AMI id by using AWS CLI and jQuery.
I have managed to solve this with the following command:
aws ec2 describe-images --owners self --output json | jq '.Images[] | {ImageId}' | jq --raw-output '.ImageId'