Token exchange service
The token exchange service component (aws.greengrass.TokenExchangeService
) provides Amazon
credentials that you can use to interact with Amazon services in your custom components.
The token exchange service runs an Amazon Elastic Container Service (Amazon ECS) container instance as a local server. This
local server connects to the Amazon IoT credentials provider using the Amazon IoT role alias that you
configure in the Greengrass core nucleus
component. The component provides an environment variable,
AWS_CONTAINER_CREDENTIALS_FULL_URI
, that defines the URI to this local server.
When a component creates an Amazon SDK client, the client recognizes this URI environment
variable to connect to the token exchange service and retrieve Amazon credentials. This allows
Greengrass core devices to call Amazon service operations. For more information about how to use this
component in custom components, see Interact with Amazon services.
Support to acquire Amazon credentials in this way was added to the Amazon SDKs on July 13th, 2016. Your component must use an Amazon SDK version that was created on or after that date. For more information, see Using a supported Amazon SDK in the Amazon Elastic Container Service Developer Guide.
Versions
This component has the following versions:
-
2.0.x
Type
This component is a generic component (aws.greengrass.generic
). The Greengrass nucleus runs the component's lifecycle
scripts.
For more information, see Component types.
Operating system
This component can be installed on core devices that run the following operating systems:
Linux
Windows
Dependencies
This component doesn't have any dependencies.
Configuration
This component doesn't have any configuration parameters.
Local log file
This component uses the same log file as the Greengrass nucleus component.
To view this component's logs
-
Run the following command on the core device to view this component's log file in real time. Replace
/greengrass/v2
orC:\greengrass\v2
with the path to the Amazon IoT Greengrass root folder.
Changelog
The following table describes the changes in each version of the component.
Version |
Changes |
---|---|
2.0.3 |
Initial version. |