terraform/terraform/graph_builder.go

70 lines
1.9 KiB
Go

package terraform
import (
"log"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/internal/logging"
"github.com/hashicorp/terraform/tfdiags"
)
// GraphBuilder is an interface that can be implemented and used with
// Terraform to build the graph that Terraform walks.
type GraphBuilder interface {
// Build builds the graph for the given module path. It is up to
// the interface implementation whether this build should expand
// the graph or not.
Build(addrs.ModuleInstance) (*Graph, tfdiags.Diagnostics)
}
// BasicGraphBuilder is a GraphBuilder that builds a graph out of a
// series of transforms and (optionally) validates the graph is a valid
// structure.
type BasicGraphBuilder struct {
Steps []GraphTransformer
Validate bool
// Optional name to add to the graph debug log
Name string
}
func (b *BasicGraphBuilder) Build(path addrs.ModuleInstance) (*Graph, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
g := &Graph{Path: path}
var lastStepStr string
for _, step := range b.Steps {
if step == nil {
continue
}
log.Printf("[TRACE] Executing graph transform %T", step)
err := step.Transform(g)
if thisStepStr := g.StringWithNodeTypes(); thisStepStr != lastStepStr {
log.Printf("[TRACE] Completed graph transform %T with new graph:\n%s ------", step, logging.Indent(thisStepStr))
lastStepStr = thisStepStr
} else {
log.Printf("[TRACE] Completed graph transform %T (no changes)", step)
}
if err != nil {
if nf, isNF := err.(tfdiags.NonFatalError); isNF {
diags = diags.Append(nf.Diagnostics)
} else {
diags = diags.Append(err)
return g, diags
}
}
}
// Validate the graph structure
if b.Validate {
if err := g.Validate(); err != nil {
log.Printf("[ERROR] Graph validation failed. Graph:\n\n%s", g.String())
diags = diags.Append(err)
return nil, diags
}
}
return g, diags
}