This commit adds support for native list variables and outputs, building
up on the previous change to state. Interpolation functions now return
native lists in preference to StringList.
List variables are defined like this:
variable "test" {
# This can also be inferred
type = "list"
default = ["Hello", "World"]
}
output "test_out" {
value = "${var.a_list}"
}
This results in the following state:
```
...
"outputs": {
"test_out": [
"hello",
"world"
]
},
...
```
And the result of terraform output is as follows:
```
$ terraform output
test_out = [
hello
world
]
```
Using the output name, an xargs-friendly representation is output:
```
$ terraform output test_out
hello
world
```
The output command also supports indexing into the list (with
appropriate range checking and no wrapping):
```
$ terraform output test_out 1
world
```
Along with maps, list outputs from one module may be passed as variables
into another, removing the need for the `join(",", var.list_as_string)`
and `split(",", var.list_as_string)` which was previously necessary in
Terraform configuration.
This commit also updates the tests and implementations of built-in
interpolation functions to take and return native lists where
appropriate.
A backwards compatibility note: previously the concat interpolation
function was capable of concatenating either strings or lists. The
strings use case was deprectated a long time ago but still remained.
Because we cannot return `ast.TypeAny` from an interpolation function,
this use case is no longer supported for strings - `concat` is only
capable of concatenating lists. This should not be a huge issue - the
type checker picks up incorrect parameters, and the native HIL string
concatenation - or the `join` function - can be used to replicate the
missing behaviour.
This adds a field terraform_version to the state that represents the
Terraform version that wrote that state. If Terraform encounters a state
written by a future version, it will error. You must use at least the
version that wrote that state.
Internally we have fields to override this behavior (StateFutureAllowed),
but I chose not to expose them as CLI flags, since the user can just
modify the state directly. This is tricky, but should be tricky to
represent the horrible disaster that can happen by enabling it.
We didn't have to bump the state format version since the absense of the
field means it was written by version "0.0.0" which will always be
older. In effect though this change will always apply to version 2 of
the state since it appears in 0.7 which bumped the version for other
purposes.
When a user specifies `-target`s on a `terraform plan` and stores
the resulting diff in a plan file using `-out` - it usually works just
fine since the diff is scoped based on the targets.
When there are tainted resources in the state, however, graph nodes to
destroy them were popping back into the plan when it was being loaded
from a file. This was because Targets weren't being stored in the
Planfile, so Terraform didn't know to filter them out. (In the
non-Planfile scenario, we still had the Targets loaded directly from the
flags.)
By encoding Targets in with the Planfile we can ensure that the same
filters are always applied.
Backwards compatibility should be fine here, since we're just adding a
field. The gob encoder/decoder will just do the right thing (ignore/skip
the field) with planfiles stored w/ versions that don't know about
Targets.
Fixes#5183
Now that we support log line filtering (as of 0090c063) it's good to be
a bit more fussy about what log levels are assigned to different things.
Here we make a few things that are implementation details log as DEBUG,
and prevent spurious errors from EvalValidateCount where it was returning
an empty EvalValidateError rather than nil when everything was okay.
In `helper/schema` we already makes a distinction between `Default`
which is always applied and `InputDefault` which is displayed to the
user for an empty field.
But for variables we just have `Default` which is treated like
`InputDefault`. This changes it to _not_ prompt the user for a value
when the variable declaration includes a default.
Treating this as a UX bugfix and the "don't prompt for variables w/
defaults set" behavior as the originally expected behavior we were
failing to honor.
Added an already-passing test to verify and cover the `helper/schema`
behavior.
Perhaps down the road we can add a `input_default` attribute to
variables to allow similar behavior to `helper/schema` in variables, but
for now just sticking with the fix.
Fixes#2592
This reimplements my prior attempt at nipping issues where a plan did
not yield the same cycle an apply did. My prior attempt was to have
ctx.Validate generate a "Verbose" worst-case graph. It turns out that
skipping PruneDestroyTransformer to generate this graph misses important
heuristics that prevent cycles by dropping destroy nodes that are
determined to be unused.
This resulted in Validate improperly failing in scenarios where these
heuristics would have broken the cycle.
We detected the problem during the work on #1781 and worked around the
issue by reverting to the non-Verbose graph in Validate.
This commit accomplishes the original goal in a better way - by
generating the full graph and checking it once Plan has calculated the
diff. This guarantees that any graph issue that would be caught by Apply
will be caught by Plan.
Most CBD-related cycles include destroy nodes, and destroy nodes were
all being pruned from the graph before staring the Validate walk.
In practice this meant that we had scenarios that would error out with
graph cycles on Apply that _seemed_ fine during Plan.
This introduces a Verbose option to the GraphBuilder that tells it to
generate a "worst-case" graph. Validate sets this to true so that cycle
errors will always trigger at this step if they're going to happen.
(This Verbose option will be exposed as a CLI flag to `terraform graph`
in a second incoming PR.)
refs #1651
Add `-target=resource` flag to core operations, allowing users to
target specific resources in their infrastructure. When `-target` is
used, the operation will only apply to that resource and its
dependencies.
The calculated dependencies are different depending on whether we're
running a normal operation or a `terraform destroy`.
Generally, "dependencies" refers to ancestors: resources falling
_before_ the target in the graph, because their changes are required to
accurately act on the target.
For destroys, "dependencies" are descendents: those resources which fall
_after_ the target. These resources depend on our target, which is going
to be destroyed, so they should also be destroyed.
