vendor/github.com/hashicorp/terraform/configs/backend.go

   1 package configs
   2
   3 import (
   4         "github.com/hashicorp/hcl2/hcl"
   5         "github.com/hashicorp/hcl2/hcldec"
   6         "github.com/hashicorp/terraform/configs/configschema"
   7         "github.com/zclconf/go-cty/cty"
   8 )
   9
  10 // Backend represents a "backend" block inside a "terraform" block in a module
  11 // or file.
  12 type Backend struct {
  13         Type   string
  14         Config hcl.Body
  15
  16         TypeRange hcl.Range
  17         DeclRange hcl.Range
  18 }
  19
  20 func decodeBackendBlock(block *hcl.Block) (*Backend, hcl.Diagnostics) {
  21         return &Backend{
  22                 Type:      block.Labels[0],
  23                 TypeRange: block.LabelRanges[0],
  24                 Config:    block.Body,
  25                 DeclRange: block.DefRange,
  26         }, nil
  27 }
  28
  29 // Hash produces a hash value for the reciever that covers the type and the
  30 // portions of the config that conform to the given schema.
  31 //
  32 // If the config does not conform to the schema then the result is not
  33 // meaningful for comparison since it will be based on an incomplete result.
  34 //
  35 // As an exception, required attributes in the schema are treated as optional
  36 // for the purpose of hashing, so that an incomplete configuration can still
  37 // be hashed. Other errors, such as extraneous attributes, have no such special
  38 // case.
  39 func (b *Backend) Hash(schema *configschema.Block) int {
  40         // Don't fail if required attributes are not set. Instead, we'll just
  41         // hash them as nulls.
  42         schema = schema.NoneRequired()
  43         spec := schema.DecoderSpec()
  44         val, _ := hcldec.Decode(b.Config, spec, nil)
  45         if val == cty.NilVal {
  46                 val = cty.UnknownVal(schema.ImpliedType())
  47         }
  48
  49         toHash := cty.TupleVal([]cty.Value{
  50                 cty.StringVal(b.Type),
  51                 val,
  52         })
  53
  54         return toHash.Hash()
  55 }