vendor/github.com/hashicorp/terraform/terraform/transform_state.go

   1 package terraform
   2
   3 import (
   4         "fmt"
   5         "log"
   6
   7         "github.com/hashicorp/terraform/dag"
   8 )
   9
  10 // StateTransformer is a GraphTransformer that adds the elements of
  11 // the state to the graph.
  12 //
  13 // This transform is used for example by the DestroyPlanGraphBuilder to ensure
  14 // that only resources that are in the state are represented in the graph.
  15 type StateTransformer struct {
  16         Concrete ConcreteResourceNodeFunc
  17
  18         State *State
  19 }
  20
  21 func (t *StateTransformer) Transform(g *Graph) error {
  22         // If the state is nil or empty (nil is empty) then do nothing
  23         if t.State.Empty() {
  24                 return nil
  25         }
  26
  27         // Go through all the modules in the diff.
  28         log.Printf("[TRACE] StateTransformer: starting")
  29         var nodes []dag.Vertex
  30         for _, ms := range t.State.Modules {
  31                 log.Printf("[TRACE] StateTransformer: Module: %v", ms.Path)
  32
  33                 // Go through all the resources in this module.
  34                 for name, rs := range ms.Resources {
  35                         log.Printf("[TRACE] StateTransformer: Resource %q: %#v", name, rs)
  36
  37                         // Add the resource to the graph
  38                         addr, err := parseResourceAddressInternal(name)
  39                         if err != nil {
  40                                 panic(fmt.Sprintf(
  41                                         "Error parsing internal name, this is a bug: %q", name))
  42                         }
  43
  44                         // Very important: add the module path for this resource to
  45                         // the address. Remove "root" from it.
  46                         addr.Path = ms.Path[1:]
  47
  48                         // Add the resource to the graph
  49                         abstract := &NodeAbstractResource{Addr: addr}
  50                         var node dag.Vertex = abstract
  51                         if f := t.Concrete; f != nil {
  52                                 node = f(abstract)
  53                         }
  54
  55                         nodes = append(nodes, node)
  56                 }
  57         }
  58
  59         // Add all the nodes to the graph
  60         for _, n := range nodes {
  61                 g.Add(n)
  62         }
  63
  64         return nil
  65 }