- revise timeout for curl checks against instance metadata (Thanks
@jmorten)
 
- curl timeout now respects the AWS_METADATA_SERVICE_TIMEOUT
environment variable (like boto3)
 
- Added new functions: 
is_ecs() to check whether R is
running in an Elastic Container Store (ECS) instance, and
ecs_metadata() to retrieve credentials from the container.
(#2, h/t @jon-mago) 
- Now supports querying ECS task role
 
- Previous 
.onLoad() functionality added in 0.1.3 is now
moved to .onAttach() to comply with CRAN policy. 
- Added a function 
instance_document() that returns a
list of the “instance
identity document” information. This is useful for identifying the
region an instance is running in. 
- When the package is loaded on an EC2 instance (as identified by
is_ec2() during package load), the package attempts to set
the AWS_DEFAULT_REGION environment variable if it has not
already been specified. This helps handle request signing. 
- Added a function 
is_ec2() that returns a logical based
on whether metadata is retrievable.