Due to how often the state and plan types are referenced throughout
Terraform, there isn't a great way to switch them out gradually. As a
consequence, this huge commit gets us from the old world to a _compilable_
new world, but still has a large number of known test failures due to
key functionality being stubbed out.
The stubs here are for anything that interacts with providers, since we
now need to do the follow-up work to similarly replace the old
terraform.ResourceProvider interface with its replacement in the new
"providers" package. That work, along with work to fix the remaining
failing tests, will follow in subsequent commits.
The aim here was to replace all references to terraform.State and its
downstream types with states.State, terraform.Plan with plans.Plan,
state.State with statemgr.State, and switch to the new implementations of
the state and plan file formats. However, due to the number of times those
types are used, this also ended up affecting numerous other parts of core
such as terraform.Hook, the backend.Backend interface, and most of the CLI
commands.
Just as with 5861dbf3fc49b19587a31816eb06f511ab861bb4 before, I apologize
in advance to the person who inevitably just found this huge commit while
spelunking through the commit history.
Previously we forced all remote state backends to be wrapped in a
BackupState wrapper that generates a local "terraform.tfstate.backup"
file before updating the remote state.
This backup mechanism was motivated by allowing users to recover a
previous state if user error caused an undesirable change such as loss
of the record of one or more resources. However, it also has the downside
of flushing a possibly-sensitive state to local disk in a location where
users may not realize its purpose and accidentally check it into version
control. Those using remote state would generally prefer that state never
be flushed to local disk at all.
The use-case of recovering older states can be dealt with for remote
backends by selecting a backend that has preservation of older versions
as a first-class feature, such as S3 versioning or Terraform Enterprise's
first-class historical state versioning mechanism.
There remains still one case where state can be flushed to local disk: if
a write to the remote backend fails during "terraform apply" then we will
still create the "errored.tfstate" file to allow the user to recover. This
seems like a reasonable compromise because this is done only in an
_exceptional_ case, and the console output makes it very clear that this
file has been created.
Fixes#15339.
We're shifting terminology from "environment" to "workspace". This takes
care of some of the main internal API surface that was using the old
terminology, though is not intended to be entirely comprehensive and is
mainly just to minimize the amount of confusion for maintainers as we
continue moving towards eliminating the old terminology.
I made this interface way back with the original backend work and I
guess I forgot to hook it up! This is becoming an issue as I'm working
on our 2nd enhanced backend that requires this information and I
realized it was hardcoded before.
This propertly uses the CLIInit interface allowing any backend to gain
access to this data.
The local backend implementation is an implementation of
backend.Enhanced that recreates all the behavior of the CLI but through
the backend interface.
Kristin Laemmert