hashicorp/terraform v1.10.0-alpha20240926 on GitHub

1.10.0-alpha20240926 (September 26, 2024)

NEW FEATURES:

Ephemeral values: Input variables and outputs can now be defined as ephemeral. Ephemeral values may only be used in certain contexts in Terraform configuration, and are not persisted to the plan or state files.
- terraform output -json now displays ephemeral outputs. The value of an ephemeral output is always null unless a plan or apply is being run. Note that terraform output (without the -json) flag does not yet display ephemeral outputs.
- ephemeralasnull function: a function takes a value of any type and returns a similar value of the same type with any ephemeral values replaced with non-ephemeral null values and all non-ephemeral values preserved.

BUG FIXES:

The error message for an invalid default value for an input variable now indicates when the problem is with a nested value in a complex data type. (#35465)
Sensitive marks could be incorrectly transferred to nested resource values, causing erroneous changes during a plan (#35501)
Allow unknown error_message values to pass the core validate step, so variable validation can be completed later during plan
(#35537)
Unencoded slashes within GitHub module source refs were being truncated and incorrectly used as subdirectories in the request path (#35552)

ENHANCEMENTS:

The element function now accepts negative indices (#35501)
Import block validation has been improved to provide more useful errors and catch more invalid cases during terraform validate (#35543)
Performance enhancements for resource evaluation, especially when large numbers of resource instances are involved (#35558)
The plan, apply, and refresh commands now produce a deprecated warning when using the -state flag. Instead use the path attribute within the local backend to modify the state file. (#35660)
backend/s3: Adds support for IAM role chaining. The backend attribute assume_role now accepts multiple elements (#35720)

UPGRADE NOTES:

backend/s3: Removes deprecated attributes for assuming IAM role. Must use the assume_role block (#35721)

EXPERIMENTS:

Experiments are only enabled in alpha releases of Terraform CLI. The following features are not yet available in stable releases.

terraform test accepts a new option -junit-xml=FILENAME. If specified, and if the test configuration is valid enough to begin executing, then Terraform writes a JUnit XML test result report to the given filename, describing similar information as included in the normal test output. (#34291)
The new command terraform rpcapi exposes some Terraform Core functionality through an RPC interface compatible with go-plugin. The exact RPC API exposed here is currently subject to change at any time, because it's here primarily as a vehicle to support the Terraform Stacks private preview and so will be broken if necessary to respond to feedback from private preview participants, or possibly for other reasons. Do not use this mechanism yet outside of Terraform Stacks private preview.
The experimental "deferred actions" feature, enabled by passing the -allow-deferral option to terraform plan, permits count and for_each arguments in module, resource, and data blocks to have unknown values and allows providers to react more flexibly to unknown values. This experiment is under active development, and so it's not yet useful to participate in this experiment

For information on prior major and minor releases, refer to their changelogs: