The AbstractResourceInstance type was storing the entire Resource from
the state, when it only needs the actual instance state. This would
cause resources to consume memory on the order of n^2, where n in the
number of instances of the resource.
Rather than attaching the entire resource state, which includes copying
each individual instance, only attach the ResourceInstance state, and
extract out the provider address from the Resource.
The main motivation here is to produce a helpful error if a user
incorrectly uses the terraform-provider- prefix (which we see on provider
VCS repositories and plugin executables) as part of the source address.
However, this also more broadly blocks "terraform-" as a prefix in
anticipation of whatever instinct causes the phenomenon where e.g.
Python's PyPI has thousands of packages whose names start with "python-",
even though everything on PyPI is for Python by definition. This is
definitely not _necessary_, but it's better to be restrictive at first
and weaken later as needed.
If the user specifies a host that isn't a provider registry in a provider
source address then we'll print out some specialized error messages for
different variants of that situation.
In particular, this includes a special case for when the error is on the
hostname "github.com", in anticipation of folks incorrectly attempting to
use GitHub repository URLs (or Go-style module paths that happen to be
on GitHub) to specify providers, so we can give a more specific hint about
that.
This is just a different presentation of an existing error case that we
are already covering in the installer tests, so there are no new tests
here. We could in principle have a test covering the exact text of these
error messages, but we don't have much precedent for command package tests
covering that level of cosmetic detail.
For Terraform v0.12 we introduced a special loading mode where we would
use the 0.11-syntax-compatible "earlyconfig" package as a heuristic to
identify situations where it was likely that the user was trying to use
0.11-only syntax that the upgrade tool might help with.
However, as the language has moved on that is no longer a suitable
heuristic in Terraform 0.13 and later: other new additions to the
language can cause the main loader to disagree with earlyconfig, which
would lead us to give poor advice about how to respond.
Instead, we'll now return the same generic "there are errors" message in
all syntax error cases. We have an extra message for errors in this
case (as compared to other commands) because "terraform init" is usually
the first command a new user interacts with and so this message gives some
extra explanation about what "terraform init" will do with the
configuration once it's valid.
This also includes a reset control character in the output of the message
as part of our ongoing mission to stop Terraform printing out whole
paragraphs of colored text, which can often be hard to read for various
reasons.
After installing providers, we validate the presence of an executable
file, and generate a selected versions lockfile. If this process fails,
notify the user. One possible cause for this is an invalid provider
package with a missing or misnamed executable file.
At the end of the EnsureProviderVersions process, we generate a lockfile
of the selected and installed provider versions. This includes a hash of
the unpacked provider directory.
When calculating this hash and generating the lockfile, we now also
verify that the provider directory contains a valid executable file. If
not, we return an error for this provider and trigger the installer's
HashPackageFailure event. Note that this event is not yet processed by
terraform init; that comes in the next commit.
Instead of searching the installed provider package directory for a
binary as we install it, we can lazily detect the executable as it is
required. Doing so allows us to separately report an invalid unpacked
package, giving the user more actionable error messages.
If we're adding a node to remove a root output from the state, the
output itself does not need to be re-evaluated. The exception for root
outputs caused them to be missed when we refactored resource destruction
to only use the existing state.
Have the output reference the expansion of a resource (via the whole
resource object), so that we can be sure we don't attempt to evaluate
that expansion during destroy.
