It's a common source of errors to try to produce JSON or YAML syntax
using string concatenation via our template language but to miss some
details like correct string escaping, quoting, required commas, etc.
The jsonencode and yamlencode functions are a better way to generate JSON
and YAML, but it's not immediately obvious that both of these functions
are available for use in external templates (via templatefile) too.
Given that questions related to this come up a lot in our community forum
and elsewhere, it seems worth having a documentation section to show the
pattern of having a template that consists only of a single function call.
When warnings appear in isolation (not accompanied by an error) it's
reasonable to want to defer resolving them for a while because they are
not actually blocking immediate work.
However, our warning messages tend to be long by default in order to
include all of the necessary context to understand the implications of
the warning, and that can make them overwhelming when combined with other
output.
As a compromise, this adds a new CLI option -compact-warnings which is
supported for all the main operation commands and which uses a more
compact format to print out warnings as long as they aren't also
accompanied by errors.
The default remains unchanged except that the threshold for consolidating
warning messages is reduced to one so that we'll now only show one of
each distinct warning summary.
Full warning messages are always shown if there's at least one error
included in the diagnostic set too, because in that case the warning
message could contain additional context to help understand the error.
There are a few situations that we've seen arise quite commonly for folks
upgrading from Terraform 0.11 to 0.12. These particular problems are not
things that Terraform 0.12 can fix automatically during upgrading, but
we can at least give some better feedback to users that they ought to be
addressed _before_ upgrading.
The provider address problem is already detected and flagged by the
"terraform 0.11checklist" command that folks should run as part of their
upgrade process, but the module address problem is not something we
noticed was lacking validation in 0.11 and so the checklist tool doesn't
cover it. Due to the lack of coverage in the checklist tool, this commit
also includes an additional section in the upgrade guide that mentions
the problem and gives instructions on how to address it.
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.
There are some differences between the Terraform CLI and Terraform Cloud ideas of workspaces.
This documentation aims to explain those differences and show different patterns for configuring the remote backend and the implications of different approaches.
As mentioned in #17871 the current example can hide the fact that the module
path plays an important role. The example's explanation is expanded.
Moreover, the verb "attach" is replaced with "map" to make the vocabulary
consistent with the wording in the documentation of the terraform state.
