AWS Classroom Series – 16/Apr/2020

How to query aws cli results

• To query the results retreived from aws cli commands, aws supports jmespath

• Pre-reqs:

  • Understanding JSON

• To Query:

  • JMESPath: Helps in writing expressions to filter and search the json data

• How to do that

1. Write a query to get all the regions

   • Basic query and store output

   aws ec2 describe-regions > regions.json
   

   • lets get the first regions name

   aws ec2 describe-regions --query "Regions[0].RegionName"
   

   • lets get all the region names

   aws ec2 describe-regions --query "Regions[*].RegionName"
   

   • lets get the last region name

   aws ec2 describe-regions --query "Regions[-1].RegionName"
   

   • other fun stuff

   aws ec2 describe-regions --query "Regions[::2].RegionName"
   aws ec2 describe-regions --query "Regions[::-1].RegionName"
   

2. Other jmes examples

   • Execute aws ec2 describe-instances > ec2info.json
   • Get image ids of all instances

   aws ec2 describe-instances --query "Reservations[*].Instances[0].ImageId"
   

   • Get Image id, Instance Id, Private Ip , Key Pair for all instances

   aws ec2 describe-instances --query "Reservations[*].Instances[0].{amiid: ImageId, instanceid: InstanceId, keypair: KeyName, PrivateIp: PrivateIpAddress}"
   

   • Write a query to describe all the images owned by amazon

   aws ec2 describe-images --owner amazon > images.json
   

   • Find count of number of images in region us-west-2 owned by amazon

   aws ec2 describe-images --owner amazon --query "length(Images[])"
   

   • Find count of number of images in region ap-south-1 owned by amazon

   aws ec2 describe-images --owner amazon --query "length(Images[])" --region ap-south-1
   

   • Write an aws cli query to find out images whose name starts with Windows and owner is microsoft

   aws ec2 describe-images --owner microsoft --query "Images[?starts_with(Name, 'Windows')]"
   

   • Show filtered information for above query

   aws ec2 describe-images --owner microsoft --query "Images[?starts_with(Name, 'Windows')].{amiid: ImageId, hypervisor: Hypervisor, virttype: VirtualizationType }"
   

   • Now try to write query to images whose name starts with aws

   aws ec2 describe-images --query "Images[?Name != `null`] |[?starts_with(Name, 'aws')].{amiid: ImageId, hypervisor: Hypervisor, virttype: VirtualizationType }"