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

   1 package terraform
   2
   3 import (
   4         "fmt"
   5
   6         "github.com/hashicorp/hcl2/hcl"
   7
   8         "github.com/hashicorp/terraform/addrs"
   9         "github.com/hashicorp/terraform/configs/configschema"
  10         "github.com/hashicorp/terraform/lang"
  11         "github.com/hashicorp/terraform/tfdiags"
  12 )
  13
  14 // EvalValidateSelfRef is an EvalNode implementation that checks to ensure that
  15 // expressions within a particular referencable block do not reference that
  16 // same block.
  17 type EvalValidateSelfRef struct {
  18         Addr           addrs.Referenceable
  19         Config         hcl.Body
  20         ProviderSchema **ProviderSchema
  21 }
  22
  23 func (n *EvalValidateSelfRef) Eval(ctx EvalContext) (interface{}, error) {
  24         var diags tfdiags.Diagnostics
  25         addr := n.Addr
  26
  27         addrStrs := make([]string, 0, 1)
  28         addrStrs = append(addrStrs, addr.String())
  29         switch tAddr := addr.(type) {
  30         case addrs.ResourceInstance:
  31                 // A resource instance may not refer to its containing resource either.
  32                 addrStrs = append(addrStrs, tAddr.ContainingResource().String())
  33         }
  34
  35         if n.ProviderSchema == nil || *n.ProviderSchema == nil {
  36                 return nil, fmt.Errorf("provider schema unavailable while validating %s for self-references; this is a bug in Terraform and should be reported", addr)
  37         }
  38
  39         providerSchema := *n.ProviderSchema
  40         var schema *configschema.Block
  41         switch tAddr := addr.(type) {
  42         case addrs.Resource:
  43                 schema, _ = providerSchema.SchemaForResourceAddr(tAddr)
  44         case addrs.ResourceInstance:
  45                 schema, _ = providerSchema.SchemaForResourceAddr(tAddr.ContainingResource())
  46         }
  47
  48         if schema == nil {
  49                 return nil, fmt.Errorf("no schema available for %s to validate for self-references; this is a bug in Terraform and should be reported", addr)
  50         }
  51
  52         refs, _ := lang.ReferencesInBlock(n.Config, schema)
  53         for _, ref := range refs {
  54                 for _, addrStr := range addrStrs {
  55                         if ref.Subject.String() == addrStr {
  56                                 diags = diags.Append(&hcl.Diagnostic{
  57                                         Severity: hcl.DiagError,
  58                                         Summary:  "Self-referential block",
  59                                         Detail:   fmt.Sprintf("Configuration for %s may not refer to itself.", addrStr),
  60                                         Subject:  ref.SourceRange.ToHCL().Ptr(),
  61                                 })
  62                         }
  63                 }
  64         }
  65
  66         return nil, diags.NonFatalErr()
  67 }