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

   1 package configs
   2
   3 import (
   4         "fmt"
   5
   6         version "github.com/hashicorp/go-version"
   7         "github.com/hashicorp/hcl2/hcl"
   8         "github.com/zclconf/go-cty/cty"
   9         "github.com/zclconf/go-cty/cty/convert"
  10 )
  11
  12 // VersionConstraint represents a version constraint on some resource
  13 // (e.g. Terraform Core, a provider, a module, ...) that carries with it
  14 // a source range so that a helpful diagnostic can be printed in the event
  15 // that a particular constraint does not match.
  16 type VersionConstraint struct {
  17         Required  version.Constraints
  18         DeclRange hcl.Range
  19 }
  20
  21 func decodeVersionConstraint(attr *hcl.Attribute) (VersionConstraint, hcl.Diagnostics) {
  22         ret := VersionConstraint{
  23                 DeclRange: attr.Range,
  24         }
  25
  26         val, diags := attr.Expr.Value(nil)
  27         if diags.HasErrors() {
  28                 return ret, diags
  29         }
  30         var err error
  31         val, err = convert.Convert(val, cty.String)
  32         if err != nil {
  33                 diags = append(diags, &hcl.Diagnostic{
  34                         Severity: hcl.DiagError,
  35                         Summary:  "Invalid version constraint",
  36                         Detail:   fmt.Sprintf("A string value is required for %s.", attr.Name),
  37                         Subject:  attr.Expr.Range().Ptr(),
  38                 })
  39                 return ret, diags
  40         }
  41
  42         if val.IsNull() {
  43                 // A null version constraint is strange, but we'll just treat it
  44                 // like an empty constraint set.
  45                 return ret, diags
  46         }
  47
  48         constraintStr := val.AsString()
  49         constraints, err := version.NewConstraint(constraintStr)
  50         if err != nil {
  51                 // NewConstraint doesn't return user-friendly errors, so we'll just
  52                 // ignore the provided error and produce our own generic one.
  53                 diags = append(diags, &hcl.Diagnostic{
  54                         Severity: hcl.DiagError,
  55                         Summary:  "Invalid version constraint",
  56                         Detail:   "This string does not use correct version constraint syntax.", // Not very actionable :(
  57                         Subject:  attr.Expr.Range().Ptr(),
  58                 })
  59                 return ret, diags
  60         }
  61
  62         ret.Required = constraints
  63         return ret, diags
  64 }