R script to fetch spot prices from AWS

spot.r

#aws ec2 describe-spot-price-history --instance-types m4.xlarge --start-time 2017-05-16T01:08:09 --end-time 2017-07-16T12:09:10 --product-descriptions "Linux/UNIX" >dump.txt

require(jsonlite)
require(ggplot2)
require(dplyr)
prices = fromJSON('/projects/dump.txt')

prices = data.frame(prices$SpotPriceHistory)
prices$Timestamp =  strptime(prices$Timestamp, '%Y-%m-%dT%H:%M:%S')
prices$Timestamp = as.POSIXct(prices$Timestamp)

prices$SpotPrice = as.numeric(prices$SpotPrice)
prices = prices%>%filter(AvailabilityZone !='us-east-1e')
prices$AvailabilityZone = factor(prices$AvailabilityZone)

ggplot(prices%>%filter(Timestamp>'2017-07-01'),aes(Timestamp,SpotPrice,color=AvailabilityZone))+
  geom_line(size=1.2)+ylim(0.065,0.085)+ theme_bw()+theme(axis.text.x = element_text(angle = 65, hjust = 1),
                                                 strip.text.x = element_text(size = 18),strip.text.y = element_text(size = 20),
                                                 axis.text=element_text(size=20),axis.title=element_text(size=20),
                                                 plot.title = element_text(size = 20),legend.text=element_text(size=20),legend.title=element_blank(),
                                                 axis.title.x=element_blank())+ labs(title = 'Spot prices of m4.xlarge on AWS, July 01-16, 2017')