Shell Script to bring EC2 SpotInstance Prices to CloudWatch.

cloudwatch-spot-price-metrics.sh

#!/bin/bash
#
# The MIT License (MIT)
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# Copyright (c) 2013 Mathias Leppich <mleppich@muhqu.de>
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set -e

INSTANCE_TYPES="m1.small m1.medium"

HISTORY_JSON="/tmp/cloudwatch-spot-price-history.json"
METRICS_JSON="/tmp/cloudwatch-spot-price-metrics.json"

which aws >/dev/null || {
  echo >&2 "'aws' not found: please install https://github.com/aws/aws-cli"
  exit 1
}

which jq >/dev/null || {
  echo >&2 "'jq' not found: please install http://stedolan.github.io/jq/"
  exit 1
}

aws ec2 describe-spot-price-history \
  --instance-types $INSTANCE_TYPES \
  --product-descriptions "Linux/UNIX" \
  --max-items 500 \
  > $HISTORY_JSON

cat $HISTORY_JSON | jq '
  [
    .SpotPriceHistory
    | sort_by(.Timestamp)
    | reverse
    | group_by(.AvailabilityZone, .InstanceType, .ProductDescription)
    | .[]
    | (.[0]
      | {
          MetricName: "SpotPrice", Unit: "Count",
          Dimensions: [
            {Name:"AvailabilityZone", Value: .AvailabilityZone},
            {Name:"InstanceType", Value: .InstanceType},
            {Name:"ProductDescription", Value: .ProductDescription}
          ],
          Value: (.SpotPrice|tonumber)
        }
      )
  ]' > $METRICS_JSON

aws cloudwatch put-metric-data \
  --namespace SpotPrice \
  --metric-data file://$METRICS_JSON

How would one use this? Can you share a scenario?

@madeby sry for the delay in response... I'm happily using it to receive alarms when the spot price has dropped below our defined threshold. That way our application is able to rebalance the number of desired instances per autoscaling group.

Hi Im A Newb, bu i have been dilignetly teaching myself about auto scaling, (ive been using windows machine and CLI) and I just got to the pont where I thought, How can i bhave a cloud watch alarm scaling out my instances when the price drops and retracting it when it increases. THis looks like just what i need but I dont have a clue how to utilise it. Can you pm Me and exsplain how i can install it. thanks Lee. Is it something that is set up on the AWS account or on my local instal of cloudwatch?

cheers. sorry for being an idiot.