terraform/terraform/eval_count_boundary.go

78 lines
2.6 KiB
Go

package terraform
import (
"fmt"
"log"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/configs"
)
// EvalCountFixZeroOneBoundaryGlobal is an EvalNode that fixes up the state
// when there is a resource count with zero/one boundary, i.e. fixing
// a resource named "aws_instance.foo" to "aws_instance.foo.0" and vice-versa.
//
// This works on the global state.
type EvalCountFixZeroOneBoundaryGlobal struct {
Config *configs.Config
}
// TODO: test
func (n *EvalCountFixZeroOneBoundaryGlobal) Eval(ctx EvalContext) (interface{}, error) {
// We'll temporarily lock the state to grab the modules, then work on each
// one separately while taking a lock again for each separate resource.
// This means that if another caller concurrently adds a module here while
// we're working then we won't update it, but that's no worse than the
// concurrent writer blocking for our entire fixup process and _then_
// adding a new module, and in practice the graph node associated with
// this eval depends on everything else in the graph anyway, so there
// should not be concurrent writers.
state := ctx.State().Lock()
moduleAddrs := make([]addrs.ModuleInstance, 0, len(state.Modules))
for _, m := range state.Modules {
moduleAddrs = append(moduleAddrs, m.Addr)
}
ctx.State().Unlock()
for _, addr := range moduleAddrs {
cfg := n.Config.DescendentForInstance(addr)
if cfg == nil {
log.Printf("[WARN] Not fixing up EachModes for %s because it has no config", addr)
continue
}
if err := n.fixModule(ctx, addr); err != nil {
return nil, err
}
}
return nil, nil
}
func (n *EvalCountFixZeroOneBoundaryGlobal) fixModule(ctx EvalContext, moduleAddr addrs.ModuleInstance) error {
ms := ctx.State().Module(moduleAddr)
cfg := n.Config.DescendentForInstance(moduleAddr)
if ms == nil {
// Theoretically possible for a concurrent writer to delete a module
// while we're running, but in practice the graph node that called us
// depends on everything else in the graph and so there can never
// be a concurrent writer.
return fmt.Errorf("[WARN] no state found for %s while trying to fix up EachModes", moduleAddr)
}
if cfg == nil {
return fmt.Errorf("[WARN] no config found for %s while trying to fix up EachModes", moduleAddr)
}
for _, r := range ms.Resources {
addr := r.Addr.Absolute(moduleAddr)
rCfg := cfg.Module.ResourceByAddr(r.Addr)
if rCfg == nil {
log.Printf("[WARN] Not fixing up EachModes for %s because it has no config", addr)
continue
}
hasCount := rCfg.Count != nil
fixResourceCountSetTransition(ctx, addr, hasCount)
}
return nil
}