AWS CLI Helpers

This repository contains a series of bash functions that make working with the AWS CLI tool easier.

Installation

Clone this repository or download the source code, then source the aws-cli-helpers file in your bash script:

#!/usr/bin/env bash

. /path/to/aws-cli-helpers

Contributing

Pull requests are welcome. Please follow Google's Shell Style Guide. Make a best effort to write tests. We use the Bash Automated Testing System (bats).

Usage

Filters

Many AWS commands accept the --filters option. This option is equally a pain in the ass as it is powerful. The functions in this library make it easier to create filters. Assuming that the output of the filter functions in the examples are captured in the $FILTERS variable, they can be used in aws commands:

aws ec2 describe-instances --filters $FILTERS

Simple filters

Create a simple filter, for example running instances.

filter "instance-state-name" "running"`

... which evaluates to:

Name=instance-state-name,Values="running"

Complex, predefined filters

Filter for running EC2 instances in a CloudFormation stack by resource:

logical_id_ec2_filter "my-stack" "MyResource"

... which evaluates to:

Name=instance-state-name,Values="running" Name=tag-key,Values="aws:cloudformation:stack-name" Name=tag-value,Values="my-stack" Name=tag-key,Values="aws:cloudformation:logical-id" Name=tag-value,Values="MyResource"

EC2

Metadata

Use the metadata function to retrieve instance metadata. Pass everything after http://169.254.169.254/latest/meta-data/ as the first argument. For example, to get the instance ID and the availability zone of the running EC2 instance, run the following commands:

metadata "instance-id"
metadata "placement/availability-zone"

Check the Instance Metadata and User Data documentation for available metadata items.

CloudFormation

Parameter values

Use the cfn_parameter function to get the value of a parameter in a CloudFormation stack.

cfn_parameter "my-stack" "SomeParameter"

Resource IDs

Use the resource_id_from_logical_id function to get the resource's unique ID given a CloudFormation stack name and resource ID.

resource_id_from_logical_id "my-stack" "MyResource"

Check the "Return Value" of the Resource Type you are referencing for the value that will be returned by this function.

EC2 w/ CloudFormation

Public IP addresses

Use the ips_from_logical_id function output the public IP addresses for EC2 instances in a CloudFormation stack associated with a resource that are running.

ips_from_logical_id "my-stack" "MyResource"

Image IDs

Use the amis_from_logical_id function output the unique image IDs that EC2 instances in a CloudFormation stack associated with a resource ID were launched from.

amis_from_logical_id "my-stack" "MyResource"

RDS

Host and port

Use the rds_*_from_instance_id functions to get an RDS instance's host and port.

# Assumes $instance_id is set
rds_host_from_instance_id "$instance_id"
rds_port_from_instance_id "$instance_id"

Note: Use resource_id_from_logical_id to get the instance ID if RDS is managed via CloudFormation.

Route 53

Records

Use the *_route53_record functions to create or delete records in Route53.

create_route53_record "www.new-record.mywebsite.com" "52.207.211.51" "Z2JSA8O07MCV3T" "A" "900"
delete_route53_record "www.new-record.mywebsite.com" "52.207.211.51" "Z2JSA8O07MCV3T" "A" "900"