EvalRefreshDependencies is used to update resource dependencies when
they don't exist, allow broken or old states to be updated. While
appending any newly found dependencies is tempting to have the largest
set available, changes to the config could conflict with the prior
dependencies causing cycles.
Since a create node cannot both depend on its destroy node AND be
CreateBeforeDestroy, the same goes for its dependencies. While we do
connect resources with dependency destroy nodes so that updates are
ordered correctly, this ordering does not make sense in the
CreateBeforeDestroy case.
If resource node is CreateBeforeDestroy, we need to remove any direct
dependencies from it to destroy nodes to prevent cycles. Since we don't
know for certain if a crate node is going to be CreateBeforeDestroy at
the time the edge is added in the graph, we add it unconditionally and
prune it out later on. The pruning happens during the CBD transformer
when the CBD destroy node reverses it's own destroy edge. The reason
this works for detecting the original edge, is that dependencies of CBD
resources are forced to be CBD themselves. This does have a false
positive where the case of the original node is NOT CBD, but this can be
taken care of later when we gather enough information in the graph to
prevent the connection in the first place.
`terraform 0.12upgrade` assumes that the configuration has passed 0.11
init, but did not explicitly check that the configuration was valid.
Certain issues would not get caught because the configuration was
syntactically valid. In this case, int or float values out of range
resulted in a panic from `Value()`.
Since running a 0.11 validate command is a breaking change, this PR
merely moves the `Value()` logic for ints and floats into `configupgrade` so
the error can be returned to the user, instead of causing a panic.
Meta.backendConfig was incorrectly treating the second return value from
loadBackendConfig as if it were go "error" rather than
tfdiags.Diagnostics, which in turn meant that it would treat warnings like
errors.
This had confusing results because it still returned that
tfdiags.Diagnostics value in its own diagnostics return value, causing the
caller to see warnings even though the backendConfig function had taken
the error codepath.
* backend/remote: Filter environment variables when loading context
Following up on #23122, the remote system (Terraform Cloud or
Enterprise) serves environment and Terraform variables using a single
type of object. We only should load Terraform variables into the
Terraform context.
Fixes https://github.com/hashicorp/terraform/issues/23283.
Following on from de652e22a26b, this introduces deprecation warnings for
when an attribute value expression is a template with only a single
interpolation sequence, and for variable type constraints given in quotes.
As with the previous commit, we allowed these deprecated forms with no
warning for a few releases after v0.12.0 to ensure that folks who need to
write cross-compatible modules for a while during upgrading would be able
to do so, but we're now marking these as explicitly deprecated to guide
users towards the new idiomatic forms.
The "terraform 0.12upgrade" tool would've already updated configurations
to not hit these warnings for those who had pre-existing configurations
written for Terraform 0.11.
The main target audience for these warnings are newcomers to Terraform who
are learning from existing examples already published in various spots on
the wider internet that may be showing older Terraform syntax, since those
folks will not be running their configurations through the upgrade tool.
These warnings will hopefully guide them towards modern Terraform usage
during their initial experimentation, and thus reduce the chances of
inadvertently adopting the less-readable legacy usage patterns in
greenfield projects.
Terraform 0.12.0 removed the need for putting references and keywords
in quotes, but we disabled the deprecation warnings for the initial
release in order to avoid creating noise for folks who were intentionally
attempting to maintain modules that were cross-compatible with both
Terraform 0.11 and Terraform 0.12.
However, with Terraform 0.12 now more widely used, the lack of these
warnings seems to be causing newcomers to copy the quoted versions from
existing examples on the internet, which is perpetuating the old and
confusing quoted form in newer configurations.
In preparation for phasing out these deprecated forms altogether in a
future major release, and for the shorter-term benefit of giving better
feedback to newcomers when they are learning from outdated examples, we'll
now re-enable those deprecation warnings, and be explicit that the old
forms are intended for removal in a future release.
In order to properly test this, we establish a new set of test
configurations that explicitly mark which warnings they are expecting and
verify that they do indeed produce those expected warnings. We also
verify that the "success" tests do _not_ produce warnings, while removing
the ones that were previously written to succeed but have their warnings
ignored.
I've seen folks ask about how to express this in resource address syntax
a number of times now, so adding this example here to illustrate how it
looks when there are multiple levels of module to traverse through.
This is redundant with other information further up the page, but having
it as an entirely separate example gives an opportunity to include more
introductory text to explain what the example is showing.
Pam Selle