This is a mostly mechanical refactor with a handful of changes which
are necessary due to the semantic difference between earlyconfig and
configs.
When parsing root and descendant modules in the module installer, we now
check the core version requirements inline. If the Terraform version is
incompatible, we drop any other module loader diagnostics. This ensures
that future language additions don't clutter the output and confuse the
user.
We also add two new checks during the module load process:
* Don't try to load a module with a `nil` source address. This is a
necessary change due to the move away from earlyconfig.
* Don't try to load a module with a blank name (i.e. `module ""`).
Because our module loading manifest uses the stringified module path
as its map key, this causes a collision with the root module, and a
later panic. This is the bug which triggered this refactor in the
first place.
Since it's already possible to activate the dependency lock file using an
environment variable, we should allow opting in to it having broken
behavior using the environment too.
It's kinda odd in retrospect that TF_PLUGIN_CACHE_DIR is the only setting
we allow to be configured both in the environment and the CLI
configuration. That means that the infrastructure for dealing with that
situation was relatively immature here and so I did some light refactoring
to make it unit-testable without actually modifying the test program's
environment.
* Add metadata functions doc to internals
* Add metadata functions to internals nav
* Review feedback
* Renamed the doc
* Fixed small typos
* Update page title
This changes which Go version we use for official releases and for
everyday development and testing.
At the time of this commit Go 1.20.1 is available but is not yet included
in goenv, the tool that we use in some environments for reacting
automatically to this file. I expect we'll upgrade to Go 1.20.1 very soon,
but this is a routine upgrade to the latest major release so that we can
start soaking in the new compiler and library behaviors throughout the
v1.5 development period.
Go 1.20 continues to support only Unicode 13, so we do not need to make
any changes to our supporting packages that also rely on Unicode data.
With the demise of the early config loader, we want to show core
version errors first, followed by backend errors, and only then
show other errors with the configuration.
Terraform Core emits a hook event every time it writes a change into the
in-memory state. Previously the local backend would just copy that into
the transient storage of the state manager, but for most state storage
implementations that doesn't really do anything useful because it just
makes another copy of the state in memory.
We originally added this hook mechanism with the intent of making
Terraform _persist_ the state each time, but we backed that out after
finding that it was a bit too aggressive and was making the state snapshot
history much harder to use in storage systems that can preserve historical
snapshots.
However, sometimes Terraform gets killed mid-apply for whatever reason and
in our previous implementation that meant always losing that transient
state, forcing the user to edit the state manually (or use "import") to
recover a useful state.
In an attempt at finding a sweet spot between these extremes, here we
change the rule so that if an apply runs for longer than 20 seconds then
we'll try to persist the state to the backend in an update that arrives
at least 20 seconds after the first update, and then again for each
additional 20 second period as long as Terraform keeps announcing new
state snapshots.
This also introduces a special interruption mode where if the apply phase
gets interrupted by SIGINT (or equivalent) then the local backend will
try to persist the state immediately in anticipation of a
possibly-imminent SIGKILL, and will then immediately persist any
subsequent state update that arrives until the apply phase is complete.
After interruption Terraform will not start any new operations and will
instead just let any already-running operations run to completion, and so
this will persist the state once per resource instance that is able to
complete before being killed.
This does mean that now long-running applies will generate intermediate
state snapshots where they wouldn't before, but there should still be
considerably fewer snapshots than were created when we were persisting
for each individual state change. We can adjust the 20 second interval
in future commits if we find that this spot isn't as sweet as first
assumed.
The existing example is already covered in the "Provisioners Without a
Resource" section, so make this one slightly different by triggering a
local-exec on multiple resources.
The terraform provider was panicking on import, because it didn't
previously have a resource type which could be imported at all. Add a
stub import function for terraform_data as a placeholder to allow the
call to complete successfully. While there's no need to actually import
a terraform_data resource, users will inevitably use this to construct
examples of import actions for learning purposes or bug reports.
This still isn't very useful even for examples however, because the
state-only nature of the terraform_data resource type means that we
can't fill in the state from only the import ID. This means that any
value in `trigger_replace` or `input` will cause a change in the next
plan. Once configuration data is available during import we can extend
this to create a logical final state based on config.
