terraform/terraform/graph_walk.go

35 lines
1.4 KiB
Go

package terraform
import (
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/dag"
"github.com/hashicorp/terraform/tfdiags"
)
// GraphWalker is an interface that can be implemented that when used
// with Graph.Walk will invoke the given callbacks under certain events.
type GraphWalker interface {
EvalContext() EvalContext
EnterPath(addrs.ModuleInstance) EvalContext
ExitPath(addrs.ModuleInstance)
EnterVertex(dag.Vertex)
ExitVertex(dag.Vertex, tfdiags.Diagnostics)
EnterEvalTree(dag.Vertex, EvalNode) EvalNode
ExitEvalTree(dag.Vertex, interface{}, error) tfdiags.Diagnostics
}
// NullGraphWalker is a GraphWalker implementation that does nothing.
// This can be embedded within other GraphWalker implementations for easily
// implementing all the required functions.
type NullGraphWalker struct{}
func (NullGraphWalker) EvalContext() EvalContext { return new(MockEvalContext) }
func (NullGraphWalker) EnterPath(addrs.ModuleInstance) EvalContext { return new(MockEvalContext) }
func (NullGraphWalker) ExitPath(addrs.ModuleInstance) {}
func (NullGraphWalker) EnterVertex(dag.Vertex) {}
func (NullGraphWalker) ExitVertex(dag.Vertex, tfdiags.Diagnostics) {}
func (NullGraphWalker) EnterEvalTree(v dag.Vertex, n EvalNode) EvalNode { return n }
func (NullGraphWalker) ExitEvalTree(dag.Vertex, interface{}, error) tfdiags.Diagnostics {
return nil
}