github.com/trawler/terraform@v0.10.8-0.20171106022149-4b1c7a1d9b48/terraform/eval_local.go (about)

     1  package terraform
     2  
     3  import (
     4  	"fmt"
     5  
     6  	"github.com/hashicorp/terraform/config"
     7  )
     8  
     9  // EvalLocal is an EvalNode implementation that evaluates the
    10  // expression for a local value and writes it into a transient part of
    11  // the state.
    12  type EvalLocal struct {
    13  	Name  string
    14  	Value *config.RawConfig
    15  }
    16  
    17  func (n *EvalLocal) Eval(ctx EvalContext) (interface{}, error) {
    18  	cfg, err := ctx.Interpolate(n.Value, nil)
    19  	if err != nil {
    20  		return nil, fmt.Errorf("local.%s: %s", n.Name, err)
    21  	}
    22  
    23  	state, lock := ctx.State()
    24  	if state == nil {
    25  		return nil, fmt.Errorf("cannot write local value to nil state")
    26  	}
    27  
    28  	// Get a write lock so we can access the state
    29  	lock.Lock()
    30  	defer lock.Unlock()
    31  
    32  	// Look for the module state. If we don't have one, create it.
    33  	mod := state.ModuleByPath(ctx.Path())
    34  	if mod == nil {
    35  		mod = state.AddModule(ctx.Path())
    36  	}
    37  
    38  	// Get the value from the config
    39  	var valueRaw interface{} = config.UnknownVariableValue
    40  	if cfg != nil {
    41  		var ok bool
    42  		valueRaw, ok = cfg.Get("value")
    43  		if !ok {
    44  			valueRaw = ""
    45  		}
    46  		if cfg.IsComputed("value") {
    47  			valueRaw = config.UnknownVariableValue
    48  		}
    49  	}
    50  
    51  	if mod.Locals == nil {
    52  		// initialize
    53  		mod.Locals = map[string]interface{}{}
    54  	}
    55  	mod.Locals[n.Name] = valueRaw
    56  
    57  	return nil, nil
    58  }
    59  
    60  // EvalDeleteLocal is an EvalNode implementation that deletes a Local value
    61  // from the state. Locals aren't persisted, but we don't need to evaluate them
    62  // during destroy.
    63  type EvalDeleteLocal struct {
    64  	Name string
    65  }
    66  
    67  func (n *EvalDeleteLocal) Eval(ctx EvalContext) (interface{}, error) {
    68  	state, lock := ctx.State()
    69  	if state == nil {
    70  		return nil, nil
    71  	}
    72  
    73  	// Get a write lock so we can access this instance
    74  	lock.Lock()
    75  	defer lock.Unlock()
    76  
    77  	// Look for the module state. If we don't have one, create it.
    78  	mod := state.ModuleByPath(ctx.Path())
    79  	if mod == nil {
    80  		return nil, nil
    81  	}
    82  
    83  	delete(mod.Locals, n.Name)
    84  
    85  	return nil, nil
    86  }