When helping folks in the community forum, I commonly see questions around
more complex patterns in transforming deep data structures into different
shapes to work with for_each. We have examples of these patterns in the
docs for the functions that they rely on, but they were not previously
very discoverable in the main configuration language documentation
sections.
Here I've moved the "Using Expressions in for_each" subsection on the
Resources page above some of the other sub-sections to hopefully make it
easier to see, and written out in more detail the two specific patterns
that answer a significant number of for_each-related user questions in
the hope that readers will be more likely to realize that the links are
relevant to what their goals.
I also added some more elaboration about the behavior of converting from
list to set in the "Using Sets" subsection, because this feature is often
a user's first encounter with the set data type and I've inferred from
some of the questions I've answered that a number of Terraform users don't
have prior experience with set data types in other languages to draw
assumptions from.
Finally, I added some similar links to the for_each patterns within the
for expression documentation itself, to try to make those examples more
visible to those who might be discovering the documentation in a different
sequence, e.g. by following a deep link shared in an answer to a question
in the community forum.
The "apply" documentation contained a simple typo, while the "plan"
documentation contained outdated information about using
"terraform plan PLANFILE" to view a plan. The latter is now a separate
command entirely, since Terraform 0.12: "terraform show PLANFILE".
This is a baby-step towards an intended future where all Terraform actions
which have side-effects in either remote objects or the Terraform state
can go through the plan+apply workflow.
This initial change is focused only on allowing plan+apply for changes to
root module output values, so that these can be written into a new state
snapshot (for consumption by terraform_remote_state elsewhere) without
having to go outside of the primary workflow by running
"terraform refresh".
This is also better than "terraform refresh" because it gives an
opportunity to review the proposed changes before applying them, as we're
accustomed to with resource changes.
The downside here is that Terraform Core was not designed to produce
accurate changesets for root module outputs. Although we added a place for
it in the plan model in Terraform 0.12, Terraform Core currently produces
inaccurate changesets there which don't properly track the prior values.
We're planning to rework Terraform Core's evaluation approach in a
forthcoming release so it would itself be able to distinguish between the
prior state and the planned new state to produce an accurate changeset,
but this commit introduces a temporary stop-gap solution of implementing
the logic up in the local backend code, where we can freeze a snapshot of
the prior state before we take any other actions and then use that to
produce an accurate output changeset to decide whether the plan has
externally-visible side-effects and render any changes to output values.
This temporary approach should be replaced by a more appropriately-placed
solution in Terraform Core in a release, which should then allow further
behaviors in similar vein, such as user-visible drift detection for
resource instances.
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 .
* website: Edit text of new TF_IGNORE env var docs
Fixing one broken link, and tidying the sentences a bit.
* typo
Co-authored-by: Pam Selle <pam@hashicorp.com>
This example doesn't really show how these values should be used. The
default of retry_on_exit_code is now already when most people want, so
this line is not needed in most cases.
I think the docs describe the new options just fine, so lets leave this
out...
This is an initial draft of documentation for this new feature of the
CLI configuration. This is mainly intended as a placeholder for now,
because there are other documentation updates pending for the new provider
namespacing and installation scheme and we'll likely want to revise these
docs to better complement the broader documentation once it's written.
Martin Atkins