Get EC2 Instance Metadata

aws.ec2metadata is a package for retrieving Amazon EC2 instance metadata from within the running instance. The package simply contains a single R list, metadata, that contains a number of functions for retrieving metadata from within an instance. Most of these functions return character strings, but some will return lists; they default to NULL if no value is returned.

library("aws.ec2metadata")

# get instance id
metadata$instance_id()

# get ami id
metadata$ami_id()

# check for IAM role (NULL if none specified)
(role <- metadata$iam_info())
# get role credentials
if (!is.null(role)) {
    metadata$iam_role("myrole")
}

# get an arbitrary metadata item
metadata$item("meta-data/placement/availability-zone")

Installation

This package is on CRAN, but to install the latest development version you can install from the cloudyr drat repository:

# latest stable version
install.packages("aws.ec2metadata", repos = c(cloudyr = "http://cloudyr.github.io/drat", getOption("repos")))

Or, to pull a potentially unstable version directly from GitHub:

if (!require("remotes")) {
    install.packages("remotes")
}
remotes::install_github("cloudyr/aws.ec2metadata")

IMDSv2 support

For IMDSv2, a token is required. Details in aws support here. Set environment variable USE_IMDS_TOKEN to "TRUE" to use this feature.

Sys.setenv(USE_IMDS_TOKEN="TRUE")