github.com/gettyimages/terraform@v0.7.6-0.20161219132226-dc052c5707a3/terraform/transform_output.go (about)

     1  package terraform
     2  
     3  import (
     4  	"github.com/hashicorp/terraform/config/module"
     5  )
     6  
     7  // OutputTransformer is a GraphTransformer that adds all the outputs
     8  // in the configuration to the graph.
     9  //
    10  // This is done for the apply graph builder even if dependent nodes
    11  // aren't changing since there is no downside: the state will be available
    12  // even if the dependent items aren't changing.
    13  type OutputTransformer struct {
    14  	Module *module.Tree
    15  }
    16  
    17  func (t *OutputTransformer) Transform(g *Graph) error {
    18  	return t.transform(g, t.Module)
    19  }
    20  
    21  func (t *OutputTransformer) transform(g *Graph, m *module.Tree) error {
    22  	// If no config, no outputs
    23  	if m == nil {
    24  		return nil
    25  	}
    26  
    27  	// Transform all the children. We must do this first because
    28  	// we can reference module outputs and they must show up in the
    29  	// reference map.
    30  	for _, c := range m.Children() {
    31  		if err := t.transform(g, c); err != nil {
    32  			return err
    33  		}
    34  	}
    35  
    36  	// If we have no outputs, we're done!
    37  	os := m.Config().Outputs
    38  	if len(os) == 0 {
    39  		return nil
    40  	}
    41  
    42  	// Add all outputs here
    43  	for _, o := range os {
    44  		// Build the node.
    45  		//
    46  		// NOTE: For now this is just an "applyable" output. As we build
    47  		// new graph builders for the other operations I suspect we'll
    48  		// find a way to parameterize this, require new transforms, etc.
    49  		node := &NodeApplyableOutput{
    50  			PathValue: normalizeModulePath(m.Path()),
    51  			Config:    o,
    52  		}
    53  
    54  		// Add it!
    55  		g.Add(node)
    56  	}
    57  
    58  	return nil
    59  }