terraform/internal/backend/unparsed_value.go

157 lines
6.4 KiB
Go

package backend
import (
"fmt"
"github.com/hashicorp/hcl/v2"
"github.com/hashicorp/terraform/configs"
"github.com/hashicorp/terraform/terraform"
"github.com/hashicorp/terraform/tfdiags"
"github.com/zclconf/go-cty/cty"
)
// UnparsedVariableValue represents a variable value provided by the caller
// whose parsing must be deferred until configuration is available.
//
// This exists to allow processing of variable-setting arguments (e.g. in the
// command package) to be separated from parsing (in the backend package).
type UnparsedVariableValue interface {
// ParseVariableValue information in the provided variable configuration
// to parse (if necessary) and return the variable value encapsulated in
// the receiver.
//
// If error diagnostics are returned, the resulting value may be invalid
// or incomplete.
ParseVariableValue(mode configs.VariableParsingMode) (*terraform.InputValue, tfdiags.Diagnostics)
}
// ParseVariableValues processes a map of unparsed variable values by
// correlating each one with the given variable declarations which should
// be from a root module.
//
// The map of unparsed variable values should include variables from all
// possible root module declarations sources such that it is as complete as
// it can possibly be for the current operation. If any declared variables
// are not included in the map, ParseVariableValues will either substitute
// a configured default value or produce an error.
//
// If this function returns without any errors in the diagnostics, the
// resulting input values map is guaranteed to be valid and ready to pass
// to terraform.NewContext. If the diagnostics contains errors, the returned
// InputValues may be incomplete but will include the subset of variables
// that were successfully processed, allowing for careful analysis of the
// partial result.
func ParseVariableValues(vv map[string]UnparsedVariableValue, decls map[string]*configs.Variable) (terraform.InputValues, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
ret := make(terraform.InputValues, len(vv))
// Currently we're generating only warnings for undeclared variables
// defined in files (see below) but we only want to generate a few warnings
// at a time because existing deployments may have lots of these and
// the result can therefore be overwhelming.
seenUndeclaredInFile := 0
for name, rv := range vv {
var mode configs.VariableParsingMode
config, declared := decls[name]
if declared {
mode = config.ParsingMode
} else {
mode = configs.VariableParseLiteral
}
val, valDiags := rv.ParseVariableValue(mode)
diags = diags.Append(valDiags)
if valDiags.HasErrors() {
continue
}
if !declared {
switch val.SourceType {
case terraform.ValueFromConfig, terraform.ValueFromAutoFile, terraform.ValueFromNamedFile:
// We allow undeclared names for variable values from files and warn in case
// users have forgotten a variable {} declaration or have a typo in their var name.
// Some users will actively ignore this warning because they use a .tfvars file
// across multiple configurations.
if seenUndeclaredInFile < 2 {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Warning,
"Value for undeclared variable",
fmt.Sprintf("The root module does not declare a variable named %q but a value was found in file %q. If you meant to use this value, add a \"variable\" block to the configuration.\n\nTo silence these warnings, use TF_VAR_... environment variables to provide certain \"global\" settings to all configurations in your organization. To reduce the verbosity of these warnings, use the -compact-warnings option.", name, val.SourceRange.Filename),
))
}
seenUndeclaredInFile++
case terraform.ValueFromEnvVar:
// We allow and ignore undeclared names for environment
// variables, because users will often set these globally
// when they are used across many (but not necessarily all)
// configurations.
case terraform.ValueFromCLIArg:
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Value for undeclared variable",
fmt.Sprintf("A variable named %q was assigned on the command line, but the root module does not declare a variable of that name. To use this value, add a \"variable\" block to the configuration.", name),
))
default:
// For all other source types we are more vague, but other situations
// don't generally crop up at this layer in practice.
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Value for undeclared variable",
fmt.Sprintf("A variable named %q was assigned a value, but the root module does not declare a variable of that name. To use this value, add a \"variable\" block to the configuration.", name),
))
}
continue
}
ret[name] = val
}
if seenUndeclaredInFile > 2 {
extras := seenUndeclaredInFile - 2
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagWarning,
Summary: "Values for undeclared variables",
Detail: fmt.Sprintf("In addition to the other similar warnings shown, %d other variable(s) defined without being declared.", extras),
})
}
// By this point we should've gathered all of the required root module
// variables from one of the many possible sources. We'll now populate
// any we haven't gathered as their defaults and fail if any of the
// missing ones are required.
for name, vc := range decls {
if _, defined := ret[name]; defined {
continue
}
if vc.Required() {
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "No value for required variable",
Detail: fmt.Sprintf("The root module input variable %q is not set, and has no default value. Use a -var or -var-file command line argument to provide a value for this variable.", name),
Subject: vc.DeclRange.Ptr(),
})
// We'll include a placeholder value anyway, just so that our
// result is complete for any calling code that wants to cautiously
// analyze it for diagnostic purposes. Since our diagnostics now
// includes an error, normal processing will ignore this result.
ret[name] = &terraform.InputValue{
Value: cty.DynamicVal,
SourceType: terraform.ValueFromConfig,
SourceRange: tfdiags.SourceRangeFromHCL(vc.DeclRange),
}
} else {
ret[name] = &terraform.InputValue{
Value: vc.Default,
SourceType: terraform.ValueFromConfig,
SourceRange: tfdiags.SourceRangeFromHCL(vc.DeclRange),
}
}
}
return ret, diags
}