3 Commits (v0.13)

Author	SHA1	Message	Date
Martin Atkins	d1bc412220	configs: Custom variable validation is no longer experimental ... All of the feedback from the experiment described enhancements that can potentially be added later without breaking changes, so this change simply removes the experiment gate from the feature as originally implemented with no changes to its functionality. Further enhancements may follow in later releases, but the goal of this change is just to ship the feature exactly as it was under the experiment. Most of the changes here are cleaning up the experiment opt-ins from our test cases. The most important parts are in configs/experiments.go and in experiments/experiment.go .	6 years ago
Martin Atkins	ff4ea042c2	config: Allow module authors to specify validation rules for variables ... The existing "type" argument allows specifying a type constraint that allows for some basic validation, but often there are more constraints on a variable value than just its type. This new feature (requiring an experiment opt-in for now, while we refine it) allows specifying arbitrary validation rules for any variable which can then cause custom error messages to be returned when a caller provides an inappropriate value. variable "example" { validation { condition = var.example != "nope" error_message = "Example value must not be \"nope\"." } } The core parts of this are designed to do as little new work as possible when no validations are specified, and thus the main new checking codepath here can therefore only run when the experiment is enabled in order to permit having validations.	6 years ago
Martin Atkins	b90fb25321	experiments: a mechanism for opt-in experimental language features ... Traditionally we've preferred to release new language features in major releases only, because we can then use the beta cycle to gather feedback on the feature and learn about any usability challenges or other situations we didn't consider during our design in time to make those changes before inclusion in a stable release. This "experiments" feature is intended to decouple the feedback cycle for new features from the major release rhythm, and thus allow us to release new features in minor releases by first releasing them as experimental for a minor release or two, adjust for any feedback gathered during that period, and then finally remove the experiment gate and enable the feature for everyone. The intended model here is that anything behind an experiment gate is subject to breaking changes even in patch releases, and so any module using these experimental features will be broken by a future Terraform upgrade. The behavior implemented here is: - Recognize a new "experiments" setting in the "terraform" block which allows module authors to explicitly opt in to experimental features. terraform { experiments = [resource_for_each] } - Generate a warning whenever loading a module that has experiments enabled, to avoid accidentally depending on experimental features and thus risking unexpected breakage on next Terraform upgrade. - We check the enabled experiments against the configuration at module load time, which means that experiments are scoped to a particular module. Enabling an experiment in one module does not automatically enable it in any other module. This experiments mechanism is itself an experiment, and so I'd like to use the resource for_each feature to trial it. Because any configuration using experiments is subject to breaking changes, we are free to adjust this experiments feature in future releases as we see fit, but once for_each is shipped without an experiment gate we'll be blocked from making significant changes to it until the next major release at least.	7 years ago