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Merge pull request #25018 from hashicorp/jbardin/destroy-modules 

Destroy nested, expanding modules
This commit is contained in:
James Bardin 2020-05-29 12:44:13 -04:00 committed by GitHub
parent 020084f6d0 1bbb59fc1b
commit 3046b790b1
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
16 changed files with 305 additions and 265 deletions
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76
terraform/context_apply_test.go
View File

@ -8980,12 +8980,6 @@ Outputs:
result_1 = hello
result_3 = hello world
module.child:
<no state>
Outputs:
result = hello
`)
if got != want {
t.Fatalf("wrong final state\ngot:\n%s\nwant:\n%s", got, want)
@ -11252,3 +11246,73 @@ output "c" {
t.Fatal("expected empty state, got:", state)
}
}
func TestContext2Apply_moduleExpandDependsOn(t *testing.T) {
m := testModuleInline(t, map[string]string{
"main.tf": `
module "child" {
count = 1
source = "./child"
depends_on = [test_instance.a, test_instance.b]
}
resource "test_instance" "a" {
}
resource "test_instance" "b" {
}
`,
"child/main.tf": `
resource "test_instance" "foo" {
}
output "myoutput" {
value = "literal string"
}
`})
p := testProvider("test")
p.ApplyFn = testApplyFn
p.DiffFn = testDiffFn
ctx := testContext2(t, &ContextOpts{
Config: m,
Providers: map[addrs.Provider]providers.Factory{
addrs.NewDefaultProvider("test"): testProviderFuncFixed(p),
},
})
_, diags := ctx.Plan()
if diags.HasErrors() {
t.Fatal(diags.ErrWithWarnings())
}
state, diags := ctx.Apply()
if diags.HasErrors() {
t.Fatal(diags.ErrWithWarnings())
}
ctx = testContext2(t, &ContextOpts{
Config: m,
Providers: map[addrs.Provider]providers.Factory{
addrs.NewDefaultProvider("test"): testProviderFuncFixed(p),
},
Destroy: true,
State: state,
})
_, diags = ctx.Plan()
if diags.HasErrors() {
t.Fatal(diags.ErrWithWarnings())
}
state, diags = ctx.Apply()
if diags.HasErrors() {
t.Fatal(diags.ErrWithWarnings())
}
if !state.Empty() {
t.Fatal("expected empty state, got:", state)
}
}

21
terraform/graph_builder_apply.go
View File

@ -160,14 +160,21 @@ func (b *ApplyGraphBuilder) Steps() []GraphTransformer {
Schemas: b.Schemas,
},
// Create a destroy node for outputs to remove them from the state.
&DestroyOutputTransformer{Destroy: b.Destroy},
// Create a destroy node for root outputs to remove them from the
// state. This does nothing unless invoked via the destroy command
// directly. A destroy is identical to a normal apply, except for the
// fact that we also have configuration to evaluate. While the rest of
// the unused nodes can be programmatically pruned (via
// pruneUnusedNodesTransformer), root module outputs only have an
// implied dependency on remote state. This means that if they exist in
// the configuration, the only signal to remove them is via the destroy
// command itself.
&destroyRootOutputTransformer{Destroy: b.Destroy},
// Prune unreferenced values, which may have interpolations that can't
// be resolved.
&PruneUnusedValuesTransformer{
Destroy: b.Destroy,
},
// We need to remove configuration nodes that are not used at all, as
// they may not be able to evaluate, especially during destroy.
// These include variables, locals, and instance expanders.
&pruneUnusedNodesTransformer{},
// Add the node to fix the state count boundaries
&CountBoundaryTransformer{

7
terraform/instance_expanders.go Normal file
View File

@ -0,0 +1,7 @@
package terraform
// graphNodeExpandsInstances is implemented by nodes that causes instances to
// be registered in the instances.Expander.
type graphNodeExpandsInstances interface {
expandsInstances()
}

3
terraform/node_local.go
View File

@ -23,8 +23,11 @@ var (
_ GraphNodeReferencer = (*nodeExpandLocal)(nil)
_ GraphNodeDynamicExpandable = (*nodeExpandLocal)(nil)
_ graphNodeTemporaryValue = (*nodeExpandLocal)(nil)
_ graphNodeExpandsInstances = (*nodeExpandLocal)(nil)
)
func (n *nodeExpandLocal) expandsInstances() {}
// graphNodeTemporaryValue
func (n *nodeExpandLocal) temporaryValue() bool {
return true

82
terraform/node_module_expand.go
View File

@ -1,7 +1,6 @@
package terraform
import (
"fmt"
"log"
"github.com/hashicorp/terraform/addrs"
@ -10,12 +9,6 @@ import (
"github.com/hashicorp/terraform/lang"
)
// graphNodeModuleCloser is an interface implemented by nodes that finalize the
// evaluation of modules.
type graphNodeModuleCloser interface {
CloseModule() addrs.Module
}
type ConcreteModuleNodeFunc func(n *nodeExpandModule) dag.Vertex
// nodeExpandModule represents a module call in the configuration that
@ -28,21 +21,22 @@ type nodeExpandModule struct {
}
var (
_ RemovableIfNotTargeted = (*nodeExpandModule)(nil)
_ GraphNodeEvalable = (*nodeExpandModule)(nil)
_ GraphNodeReferencer = (*nodeExpandModule)(nil)
_ RemovableIfNotTargeted = (*nodeExpandModule)(nil)
_ GraphNodeEvalable = (*nodeExpandModule)(nil)
_ GraphNodeReferencer = (*nodeExpandModule)(nil)
_ GraphNodeReferenceOutside = (*nodeExpandModule)(nil)
_ graphNodeExpandsInstances = (*nodeExpandModule)(nil)
)
func (n *nodeExpandModule) expandsInstances() {}
func (n *nodeExpandModule) Name() string {
return n.Addr.String() + " (expand)"
}
// GraphNodeModulePath implementation
func (n *nodeExpandModule) ModulePath() addrs.Module {
// This node represents the module call within a module,
// so return the CallerAddr as the path as the module
// call may expand into multiple child instances
return n.Addr.Parent()
return n.Addr
}
// GraphNodeReferencer implementation
@ -88,6 +82,11 @@ func (n *nodeExpandModule) References() []*addrs.Reference {
return appendResourceDestroyReferences(refs)
}
// GraphNodeReferenceOutside
func (n *nodeExpandModule) ReferenceOutside() (selfPath, referencePath addrs.Module) {
return n.Addr, n.Addr.Parent()
}
// RemovableIfNotTargeted implementation
func (n *nodeExpandModule) RemoveIfNotTargeted() bool {
// We need to add this so that this node will be removed if
@ -113,20 +112,19 @@ func (n *nodeExpandModule) EvalTree() EvalNode {
// empty resources and modules from the state.
type nodeCloseModule struct {
Addr addrs.Module
// orphaned indicates that this module has no expansion, because it no
// longer exists in the configuration
orphaned bool
}
var (
_ graphNodeModuleCloser = (*nodeCloseModule)(nil)
_ GraphNodeReferenceable = (*nodeCloseModule)(nil)
_ GraphNodeReferenceable = (*nodeCloseModule)(nil)
_ GraphNodeReferenceOutside = (*nodeCloseModule)(nil)
)
func (n *nodeCloseModule) ModulePath() addrs.Module {
mod, _ := n.Addr.Call()
return mod
return n.Addr
}
func (n *nodeCloseModule) ReferenceOutside() (selfPath, referencePath addrs.Module) {
return n.Addr.Parent(), n.Addr
}
func (n *nodeCloseModule) ReferenceableAddrs() []addrs.Referenceable {
@ -143,10 +141,6 @@ func (n *nodeCloseModule) Name() string {
return n.Addr.String() + " (close)"
}
func (n *nodeCloseModule) CloseModule() addrs.Module {
return n.Addr
}
// RemovableIfNotTargeted implementation
func (n *nodeCloseModule) RemoveIfNotTargeted() bool {
// We need to add this so that this node will be removed if
@ -160,8 +154,7 @@ func (n *nodeCloseModule) EvalTree() EvalNode {
&EvalOpFilter{
Ops: []walkOperation{walkApply, walkDestroy},
Node: &evalCloseModule{
Addr: n.Addr,
orphaned: n.orphaned,
Addr: n.Addr,
},
},
},
@ -169,8 +162,7 @@ func (n *nodeCloseModule) EvalTree() EvalNode {
}
type evalCloseModule struct {
Addr addrs.Module
orphaned bool
Addr addrs.Module
}
func (n *evalCloseModule) Eval(ctx EvalContext) (interface{}, error) {
@ -179,13 +171,6 @@ func (n *evalCloseModule) Eval(ctx EvalContext) (interface{}, error) {
state := ctx.State().Lock()
defer ctx.State().Unlock()
expander := ctx.InstanceExpander()
var currentModuleInstances []addrs.ModuleInstance
// we can't expand if we're just removing
if !n.orphaned {
currentModuleInstances = expander.ExpandModule(n.Addr)
}
for modKey, mod := range state.Modules {
if !n.Addr.Equal(mod.Addr.Module()) {
continue
@ -198,27 +183,8 @@ func (n *evalCloseModule) Eval(ctx EvalContext) (interface{}, error) {
}
}
found := false
if n.orphaned {
// we're removing the entire module, so all instances must go
found = true
} else {
// if this instance is not in the current expansion, remove it from
// the state
for _, current := range currentModuleInstances {
if current.Equal(mod.Addr) {
found = true
break
}
}
}
if !found {
if len(mod.Resources) > 0 {
// FIXME: add more info to this error
return nil, fmt.Errorf("module %q still contains resources in state", mod.Addr)
}
// empty child modules are always removed
if len(mod.Resources) == 0 && !mod.Addr.IsRoot() {
delete(state.Modules, modKey)
}
}

3
terraform/node_module_variable.go
View File

@ -27,8 +27,11 @@ var (
_ GraphNodeReferencer = (*nodeExpandModuleVariable)(nil)
_ graphNodeTemporaryValue = (*nodeExpandModuleVariable)(nil)
_ RemovableIfNotTargeted = (*nodeExpandModuleVariable)(nil)
_ graphNodeExpandsInstances = (*nodeExpandModuleVariable)(nil)
)
func (n *nodeExpandModuleVariable) expandsInstances() {}
func (n *nodeExpandModuleVariable) temporaryValue() bool {
return true
}

11
terraform/node_output.go
View File

@ -23,9 +23,12 @@ var (
_ GraphNodeReferenceable = (*nodeExpandOutput)(nil)
_ GraphNodeReferencer = (*nodeExpandOutput)(nil)
_ GraphNodeDynamicExpandable = (*nodeExpandOutput)(nil)
_ graphNodeTemporaryValue = (*NodeApplyableOutput)(nil)
_ graphNodeTemporaryValue = (*nodeExpandOutput)(nil)
_ graphNodeExpandsInstances = (*nodeExpandOutput)(nil)
)
func (n *nodeExpandOutput) expandsInstances() {}
func (n *nodeExpandOutput) temporaryValue() bool {
// this must always be evaluated if it is a root module output
return !n.Module.IsRoot()
@ -254,7 +257,6 @@ type NodeDestroyableOutput struct {
var (
_ RemovableIfNotTargeted = (*NodeDestroyableOutput)(nil)
_ GraphNodeTargetDownstream = (*NodeDestroyableOutput)(nil)
_ GraphNodeReferencer = (*NodeDestroyableOutput)(nil)
_ GraphNodeEvalable = (*NodeDestroyableOutput)(nil)
_ dag.GraphNodeDotter = (*NodeDestroyableOutput)(nil)
)
@ -281,11 +283,6 @@ func (n *NodeDestroyableOutput) TargetDownstream(targetedDeps, untargetedDeps da
return true
}
// GraphNodeReferencer
func (n *NodeDestroyableOutput) References() []*addrs.Reference {
return referencesForOutput(n.Config)
}
// GraphNodeEvalable
func (n *NodeDestroyableOutput) EvalTree() EvalNode {
return &EvalDeleteOutput{

53
terraform/node_output_orphan.go
View File

@ -1,53 +0,0 @@
package terraform
import (
"fmt"
"github.com/hashicorp/terraform/addrs"
)
// NodeOutputOrphan represents an output that is an orphan.
type NodeOutputOrphan struct {
Addr addrs.AbsOutputValue
}
var (
_ GraphNodeModuleInstance = (*NodeOutputOrphan)(nil)
_ GraphNodeReferenceable = (*NodeOutputOrphan)(nil)
_ GraphNodeReferenceOutside = (*NodeOutputOrphan)(nil)
_ GraphNodeEvalable = (*NodeOutputOrphan)(nil)
)
func (n *NodeOutputOrphan) Name() string {
return fmt.Sprintf("%s (orphan)", n.Addr.String())
}
// GraphNodeReferenceOutside implementation
func (n *NodeOutputOrphan) ReferenceOutside() (selfPath, referencePath addrs.Module) {
return referenceOutsideForOutput(n.Addr)
}
// GraphNodeReferenceable
func (n *NodeOutputOrphan) ReferenceableAddrs() []addrs.Referenceable {
return referenceableAddrsForOutput(n.Addr)
}
// GraphNodeModuleInstance
func (n *NodeOutputOrphan) Path() addrs.ModuleInstance {
return n.Addr.Module
}
// GraphNodeModulePath
func (n *NodeOutputOrphan) ModulePath() addrs.Module {
return n.Addr.Module.Module()
}
// GraphNodeEvalable
func (n *NodeOutputOrphan) EvalTree() EvalNode {
return &EvalOpFilter{
Ops: []walkOperation{walkRefresh, walkApply, walkDestroy},
Node: &EvalDeleteOutput{
Addr: n.Addr,
},
}
}

24
terraform/node_resource_apply.go
View File

@ -6,7 +6,6 @@ import (
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/dag"
"github.com/hashicorp/terraform/lang"
"github.com/hashicorp/terraform/states"
)
// nodeExpandApplyableResource handles the first layer of resource
@ -23,8 +22,11 @@ var (
_ GraphNodeReferencer = (*nodeExpandApplyableResource)(nil)
_ GraphNodeConfigResource = (*nodeExpandApplyableResource)(nil)
_ GraphNodeAttachResourceConfig = (*nodeExpandApplyableResource)(nil)
_ graphNodeExpandsInstances = (*nodeExpandApplyableResource)(nil)
)
func (n *nodeExpandApplyableResource) expandsInstances() {}
func (n *nodeExpandApplyableResource) References() []*addrs.Reference {
return (&NodeApplyableResource{NodeAbstractResource: n.NodeAbstractResource}).References()
}
@ -48,26 +50,6 @@ func (n *nodeExpandApplyableResource) DynamicExpand(ctx EvalContext) (*Graph, er
})
}
// Lock the state while we inspect it to find any resources orphaned by
// changes in module expansion.
state := ctx.State().Lock()
defer ctx.State().Unlock()
var orphans []*states.Resource
for _, res := range state.Resources(n.Addr) {
found := false
for _, m := range moduleInstances {
if m.Equal(res.Addr.Module) {
found = true
break
}
}
// Address form state was not found in the current config
if !found {
orphans = append(orphans, res)
}
}
return &g, nil
}

12
terraform/terraform_test.go
View File

@ -441,12 +441,6 @@ const testTerraformApplyEmptyModuleStr = `
Outputs:
end = XXXX
module.child:
<no state>
Outputs:
aws_route53_zone_id = XXXX
`
const testTerraformApplyDependsCreateBeforeStr = `
@ -661,12 +655,6 @@ aws_instance.bar:
provider = provider["registry.terraform.io/hashicorp/aws"]
foo = true
type = aws_instance
module.child:
<no state>
Outputs:
leader = true
`
const testTerraformApplyModuleDestroyOrderStr = `

178
terraform/transform_destroy_edge.go
View File

@ -2,6 +2,7 @@ package terraform
import (
"log"
"sort"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/states"
@ -163,46 +164,141 @@ func (t *DestroyEdgeTransformer) Transform(g *Graph) error {
}
}
return t.pruneResources(g)
}
// If there are only destroy instances for a particular resource, there's no
// reason for the resource node to prepare the state. Remove Resource nodes so
// that they don't fail by trying to evaluate a resource that is only being
// destroyed along with its dependencies.
func (t *DestroyEdgeTransformer) pruneResources(g *Graph) error {
for _, v := range g.Vertices() {
n, ok := v.(*nodeExpandApplyableResource)
if !ok {
continue
}
// if there are only destroy dependencies, we don't need this node
descendents, err := g.Descendents(n)
if err != nil {
return err
}
nonDestroyInstanceFound := false
for _, v := range descendents {
if _, ok := v.(*NodeApplyableResourceInstance); ok {
nonDestroyInstanceFound = true
break
}
}
if nonDestroyInstanceFound {
continue
}
// connect all the through-edges, then delete the node
for _, d := range g.DownEdges(n) {
for _, u := range g.UpEdges(n) {
g.Connect(dag.BasicEdge(u, d))
}
}
log.Printf("DestroyEdgeTransformer: pruning unused resource node %s", dag.VertexName(n))
g.Remove(n)
}
return nil
}
// Remove any nodes that aren't needed when destroying modules.
// Variables, outputs, locals, and expanders may not be able to evaluate
// correctly, so we can remove these if nothing depends on them. The module
// closers also need to disable their use of expansion if the module itself is
// no longer present.
type pruneUnusedNodesTransformer struct {
}
func (t *pruneUnusedNodesTransformer) Transform(g *Graph) error {
// We need a reverse depth first walk of modules, processing them in order
// from the leaf modules to the root. This allows us to remove unneeded
// dependencies from child modules, freeing up nodes in the parent module
// to also be removed.
// First collect the nodes into their respective modules based on
// configuration path.
moduleMap := make(map[string]pruneUnusedNodesMod)
for _, v := range g.Vertices() {
var path addrs.Module
switch v := v.(type) {
case GraphNodeModulePath:
path = v.ModulePath()
default:
continue
}
m := moduleMap[path.String()]
m.addr = path
m.nodes = append(m.nodes, v)
moduleMap[path.String()] = m
}
// now we need to restructure the modules so we can sort them
var modules []pruneUnusedNodesMod
for _, mod := range moduleMap {
modules = append(modules, mod)
}
// Sort them by path length, longest first, so that start with the deepest
// modules. The order of modules at the same tree level doesn't matter, we
// just need to ensure that child modules are processed before parent
// modules.
sort.Slice(modules, func(i, j int) bool {
return len(modules[i].addr) > len(modules[j].addr)
})
for _, mod := range modules {
mod.removeUnused(g)
}
return nil
}
// pruneUnusedNodesMod is a container to hold the nodes that belong to a
// particular configuration module for the pruneUnusedNodesTransformer
type pruneUnusedNodesMod struct {
addr addrs.Module
nodes []dag.Vertex
}
// Remove any unused locals, variables, outputs and expanders. Since module
// closers can also lookup expansion info to detect orphaned instances, disable
// them if their associated expander is removed.
func (m *pruneUnusedNodesMod) removeUnused(g *Graph) {
// We modify the nodes slice during processing here.
// Make a copy so no one is surprised by this changing in the future.
nodes := make([]dag.Vertex, len(m.nodes))
copy(nodes, m.nodes)
// since we have no defined structure within the module, just cycle through
// the nodes in each module until there are no more removals
removed := true
for {
if !removed {
return
}
removed = false
for i := 0; i < len(nodes); i++ {
// run this in a closure, so we can return early rather than
// dealing with complex looping and labels
func() {
n := nodes[i]
switch n.(type) {
case graphNodeTemporaryValue:
// temporary value, which consist of variables, locals, and
// outputs, must be kept if anything refers to them.
if n, ok := n.(GraphNodeModulePath); ok {
// root outputs always have an implicit dependency on
// remote state.
if n.ModulePath().IsRoot() {
return
}
}
for _, v := range g.UpEdges(n) {
// keep any value which is connected through a
// reference
if _, ok := v.(GraphNodeReferencer); ok {
return
}
}
case graphNodeExpandsInstances:
// Any nodes that expand instances are kept when their
// instances may need to be evaluated.
for _, v := range g.UpEdges(n) {
switch v.(type) {
case graphNodeExpandsInstances:
// expanders can always depend on module expansion
// themselves
return
case GraphNodeResourceInstance:
// resource instances always depend on their
// resource node, which is an expander
return
}
}
default:
return
}
log.Printf("[DEBUG] pruneUnusedNodes: %s is no longer needed, removing", dag.VertexName(n))
g.Remove(n)
removed = true
// remove the node from our iteration as well
last := len(nodes) - 1
nodes[i], nodes[last] = nodes[last], nodes[i]
nodes = nodes[:last]
}()
}
}
}

39
terraform/transform_module_expansion.go
View File

@ -3,6 +3,7 @@ package terraform
import (
"log"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/configs"
"github.com/hashicorp/terraform/dag"
)
@ -42,6 +43,11 @@ func (t *ModuleExpansionTransformer) Transform(g *Graph) error {
// handled by the RemovedModuleTransformer, and those module closers are in
// the graph already, and need to be connected to their parent closers.
for _, v := range g.Vertices() {
// skip closers so they don't attach to themselves
if _, ok := v.(*nodeCloseModule); ok {
continue
}
// any node that executes within the scope of a module should be a
// GraphNodeModulePath
pather, ok := v.(GraphNodeModulePath)
@ -49,13 +55,23 @@ func (t *ModuleExpansionTransformer) Transform(g *Graph) error {
continue
}
if closer, ok := t.closers[pather.ModulePath().String()]; ok {
// The module root depends on each child resource instance, since
// The module closer depends on each child resource instance, since
// during apply the module expansion will complete before the
// individual instances are applied.
g.Connect(dag.BasicEdge(closer, v))
}
}
// Modules implicitly depend on their child modules, so connect closers to
// other which contain their path.
for _, c := range t.closers {
for _, d := range t.closers {
if len(d.Addr) > len(c.Addr) && c.Addr.Equal(d.Addr[:len(c.Addr)]) {
g.Connect(dag.BasicEdge(c, d))
}
}
}
return nil
}
@ -91,11 +107,26 @@ func (t *ModuleExpansionTransformer) transform(g *Graph, c *configs.Config, pare
t.closers[c.Path.String()] = closer
for _, childV := range g.Vertices() {
pather, ok := childV.(GraphNodeModulePath)
if !ok {
// don't connect a node to itself
if childV == v {
continue
}
if pather.ModulePath().Equal(c.Path) {
var path addrs.Module
switch t := childV.(type) {
case GraphNodeDestroyer:
// skip destroyers, as they can only depend on other resources.
continue
case GraphNodeModulePath:
path = t.ModulePath()
case GraphNodeReferenceOutside:
path, _ = t.ReferenceOutside()
default:
continue
}
if path.Equal(c.Path) {
log.Printf("[TRACE] ModuleExpansionTransformer: %s must wait for expansion of %s", dag.VertexName(childV), c.Path)
g.Connect(dag.BasicEdge(childV, v))
}

2
terraform/transform_orphan_output.go
View File

@ -51,7 +51,7 @@ func (t *OrphanOutputTransformer) transform(g *Graph, ms *states.Module) error {
continue
}
g.Add(&NodeOutputOrphan{
g.Add(&NodeDestroyableOutput{
Addr: addrs.OutputValue{Name: name}.Absolute(moduleAddr),
})
}

6
terraform/transform_output.go
View File

@ -53,14 +53,14 @@ func (t *OutputTransformer) transform(g *Graph, c *configs.Config) error {
return nil
}
// DestroyOutputTransformer is a GraphTransformer that adds nodes to delete
// destroyRootOutputTransformer is a GraphTransformer that adds nodes to delete
// outputs during destroy. We need to do this to ensure that no stale outputs
// are ever left in the state.
type DestroyOutputTransformer struct {
type destroyRootOutputTransformer struct {
Destroy bool
}
func (t *DestroyOutputTransformer) Transform(g *Graph) error {
func (t *destroyRootOutputTransformer) Transform(g *Graph) error {
// Only clean root outputs on a full destroy
if !t.Destroy {
return nil

50
terraform/transform_reference.go
View File

@ -254,56 +254,6 @@ func (t AttachDependenciesTransformer) Transform(g *Graph) error {
return nil
}
// PruneUnusedValuesTransformer is a GraphTransformer that removes local,
// variable, and output values which are not referenced in the graph. If these
// values reference a resource that is no longer in the state the interpolation
// could fail.
type PruneUnusedValuesTransformer struct {
Destroy bool
}
func (t *PruneUnusedValuesTransformer) Transform(g *Graph) error {
// Pruning a value can effect previously checked edges, so loop until there
// are no more changes.
for removed := 0; ; removed = 0 {
for _, v := range g.Vertices() {
// we're only concerned with values that don't need to be saved in state
switch v := v.(type) {
case graphNodeTemporaryValue:
if !v.temporaryValue() {
continue
}
default:
continue
}
dependants := g.UpEdges(v)
// any referencers in the dependents means we need to keep this
// value for evaluation
removable := true
for _, d := range dependants.List() {
if _, ok := d.(GraphNodeReferencer); ok {
removable = false
break
}
}
if removable {
log.Printf("[TRACE] PruneUnusedValuesTransformer: removing unused value %s", dag.VertexName(v))
g.Remove(v)
removed++
}
}
if removed == 0 {
break
}
}
return nil
}
// ReferenceMap is a structure that can be used to efficiently check
// for references on a graph, mapping internal reference keys (as produced by
// the mapKey method) to one or more vertices that are identified by each key.

3
terraform/transform_removed_modules.go
View File

@ -35,8 +35,7 @@ func (t *RemovedModuleTransformer) Transform(g *Graph) error {
// add closers to collect any module instances we're removing
for _, modAddr := range removed {
closer := &nodeCloseModule{
Addr: modAddr,
orphaned: true,
Addr: modAddr,
}
g.Add(closer)
}