Implicit move statement for modules previously using `count` and
then moving to use `enabled`, or vice versa.
Signed-off-by: Diogenes Fernandes <diofeher@gmail.com>
Earlier work started to reshape this API to follow the dependency inversion
style, but didn't go so far as treating the package fetcher as an argument
because so far it hasn't offered any customizable policy anyway.
In future commits we will be introducing some policy arguments for the
package fetcher, and so this is some preparation work where we move the
responsibility for calling getmodules.NewPackageFetcher() out into the
caller of initwd.NewModuleInstaller().
This changes the API consumed by a bunch of unit testing helpers, so
splitting this out into its own commit should hopefully make future
commits more focused. The module installer now explicitly supports being
instantiated without a registry client or a remote package fetcher and
will in that case return an error if it's asked to install from anywhere
other than local relative directories. Most of our existing tests are
comfortable running under that constraint and so will not need any further
work in later commits that will change the signature of
getmodules.NewPackageFetcher.
However, a couple tests in package initwd _itself_ were making use of the
esoteric legacy support for treating an absolute filesystem path as a funny
sort of remote source, and so for now those will instantiate their own
package fetcher. Future commits that change the NewPackageFetcher signature
will need to offer a concession for those two tests.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
* Rename module name from "github.com/hashicorp/terraform" to "github.com/placeholderplaceholderplaceholder/opentf".
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Gofmt.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Regenerate protobuf.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Fix comments.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Undo issue and pull request link changes.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Undo comment changes.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Fix comment.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* Undo some link changes.
Signed-off-by: Jakub Martin <kubam@spacelift.io>
* make generate && make protobuf
Signed-off-by: Jakub Martin <kubam@spacelift.io>
---------
Signed-off-by: Jakub Martin <kubam@spacelift.io>
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.
The dag package did not previously provide a topological walk of a given
graph. While the existing combination of a transitive reduction with a
depth-first walk appeared to accomplish this, depth-first is only
equivalent with a simple tree. If there are multiple paths to a node, a
depth-first approach will skip dependencies from alternate paths.
* refactor: Use tfaddr for provider address parsing
* refactor: Use tfaddr for module address parsing
* deps: introduce hashicorp/terraform-registry-address
We introduced the addrs.UniqueKey and addrs.UniqueKeyer mechanics as part
of implementing the ValidateMoves and ApplyMoves functions, as a way to
better encapsulate the solution to the problem that lots of our address
types aren't comparable and so cannot be used directly as map keys.
However, exposing addrs.UniqueKey handling directly in the logic adds
various noise to the algorithms and, in particular, obscures the fact that
MoveResults.Changes and MoveResult.Blocked both have different map key
types.
Here then we'll use the new addrs.Map helper type, which encapsulates the
idea of a map from an addrs.UniqueKeyer type to an arbitrary value type,
using the unique keys as the map keys internally. This does unfortunately
mean that we lose the conventional Go map access syntax and have to use
a method-based API instead, but I (subjectively) think that's an okay
compromise in return for avoiding the need to keep track inline of which
addrs.UniqueKey values correspond with which real addresses.
This is intended as an entirely-mechanical change, with equivalent
behavior to what it replaced. If anything here is doing something
materially different than what it replaced then that's a mistake.
Terraform uses "implied" move statements to represent the situation where
it automatically handles a switch from count to no-count on a resource.
Because that situation requires targeting only a specific resource
instance inside a specific module instance, implied move statements are
always presented as if they had been declared in the root module and then
traversed through the exact module instance path to reach the target
resource.
However, that means they can potentially cross a module package boundary,
if the changed resource belongs to an external module. Normally we
prohibit that to avoid the root module depending on implementation details
of the called module, but Terraform generates these implied statements
based only on information in the called module and so there's no need to
apply that same restriction to implied move statements, which will always
have source and destination addresses belonging to the same module
instance.
This change therefore fixes a misbehavior where Terraform would reject
an attempt to switch from no-count to count in a called module, where
previously the author of the calling configuration had no recourse to fix
it because the change has actually happened upstream.
Create a separate `validateMoveStatementGraph` function so that
`ValidateMoves` and `ApplyMoves` both check the same conditions. Since
we're not using the builtin `graph.Validate` method, because we may have
multiple roots and want better cycle diagnostics, we need to add checks
for self references too. While multiple roots are an error enforced by
`Validate` for the concurrent walk, they are OK when using
`TransitiveReduction` and `ReverseDepthFirstWalk`, so we can skip that
check.
Apply moves must first use `TransitiveReduction` to reduce the graph,
otherwise nodes may be skipped if they are passed over by a transitive
edge.
Changing only the index on a nested module will cause all nested moves
to create cycles, since their full addresses will match both the From
and To addresses. When building the dependency graph, check if the
parent is only changing the index of the containing module, and prevent
the backwards edge for the move.
When applying module `moved` statements by iterating through modules in
state, we previously required an exact match from the `moved`
statement's `from` field and the module address. This permitted moving
resources directly inside a module, but did not recur into module calls
within those moved modules.
This commit moves that exact match requirement so that it only applies
to `moved` statements targeting resources. In turn this allows nested
modules to be moved.
Earlier work to make "terraform init" interruptible made the getproviders
package context-aware in order to allow provider installation to be cancelled.
Here we make a similar change for module installation, which is now also
cancellable with SIGINT. This involves plumbing context through initwd and
getmodules. Functions which can make network requests now include a context
parameter whose cancellation cancels those requests.
Since the module installation code is shared, "terraform get" is now
also interruptible during module installation.
Based on feedback during earlier alpha releases, we've decided to move
forward with the current design for the first phase of config-driven
refactoring.
Therefore here we've marked the experiment as concluded with no changes
to the most recent incarnation of the functionality. The other changes
here are all just updating test fixtures to no longer declare that they
are using experimental features.
Our previous rule for implicitly moving from IntKey(0) to NoKey would
apply that move even when the current resource configuration uses
for_each, because we were only considering whether "count" were set.
Previously this was relatively harmless because the resource instance in
question would end up planned for deletion anyway: neither an IntKey nor
a NoKey are valid keys for for_each.
Now that we're going to be announcing these moves explicitly in the UI,
it would be confusing to see Terraform report that IntKey moved to NoKey
in a situation where the config changed from count to for_each, so to
address that we'll only generate the implied statement if neither
repetition argument is set.
When we originally stubbed ApplyMoves we didn't know yet how exactly we'd
be using the result, so we made it a double-indexed map allowing looking
up moves in both directions.
However, in practice we only actually need to look up old addresses by new
addresses, and so this commit first removes the double indexing so that
each move is only represented by one element in the map.
We also need to describe situations where a move was blocked, because in
a future commit we'll generate some warnings in those cases. Therefore
ApplyMoves now returns a MoveResults object which contains both a map of
changes and a map of blocks. The map of blocks isn't used yet as of this
commit, but we'll use it in a later commit to produce warnings within
the "terraform" package.
Per our rule that the content of the state can never make a move statement
invalid, our behavior for two objects trying to occupy the same address
will be to just ignore that and let the object already at the address
take priority.
For the moment this is silent from an end-user perspective and appears
only in our internal logs. However, I'm hoping that our future planned
adjustment to the interface of this function will include some way to
allow reporting these collisions in some end-user-visible way, either as
a separate warning per collision or as a single warning that collects
together all of the collisions into a single message somehow.
This situation can arise both because the previous run state already
contained an object at the target address of a move and because more than
one move ends up trying to target the same location. In the latter case,
which one "wins" is decided by our depth-first traversal order, which is
in turn derived from our chaining and nesting rules and is therefore
arbitrary but deterministic.
This new function complements the existing function FindMoveStatements
by potentially generating additional "implied" move statements that aren't
written explicit in the configuration but that we'll infer by comparing
the configuration and te previous run state.
The goal here is to infer only enough to replicate the effect of the
"count boundary fixup" graph node (terraform.NodeCountBoundary) that we
currently use to deal with this concern of preserving the zero-instance
when switching between "count" and not "count".
This is just dead code for now. A subsequent commit will introduce this
into the "terraform" package while also removing
terraform.NodeCountBoundary, thus achieving the same effect as before but
in a way that'll get reported in the UI as a move, using the same language
that we'd use for an explicit move statement.
When originally filling out these test cases we didn't yet have the logic
in place to detect chained moves and so this test couldn't succeed in
spite of being correct.
We now have chain-detection implemented and so consequently we can also
detect cyclic chains. This commit largely just enables the original test
unchanged, although it does include the text of the final error message
for reporting cyclic move chains which wasn't yet finalized when we were
stubbing out this test case originally.
Here we wire through the "move results" into the graph walk data
structures so that all of the the nodes which produce
plans.ResourceInstanceChange values can capture the "PrevRunAddr" for
each resource instance.
This doesn't actually quite work yet, because the logic in Context.Plan
isn't actually correct and so the updated state from
refactoring.ApplyMoves isn't actually visible as the "previous run state".
For that reason, the context test in this commit is currently skipped,
with the intent of re-enabling it once the updated state is properly
propagating into the plan graph walk and thus we can actually react to
the result of the move while choosing actions for those addresses.
