terraform/internal/command/meta_vars.go

258 lines
8.2 KiB
Go
Raw Permalink Normal View History

package command
import (
"fmt"
"io/ioutil"
"os"
"strings"
"github.com/hashicorp/hcl/v2"
"github.com/hashicorp/hcl/v2/hclsyntax"
hcljson "github.com/hashicorp/hcl/v2/json"
"github.com/hashicorp/terraform/internal/backend"
"github.com/hashicorp/terraform/internal/configs"
"github.com/hashicorp/terraform/internal/terraform"
"github.com/hashicorp/terraform/internal/tfdiags"
)
2019-07-18 20:19:39 +02:00
// VarEnvPrefix is the prefix for environment variables that represent values
// for root module input variables.
const VarEnvPrefix = "TF_VAR_"
// collectVariableValues inspects the various places that root module input variable
// values can come from and constructs a map ready to be passed to the
// backend as part of a backend.Operation.
//
// This method returns diagnostics relating to the collection of the values,
// but the values themselves may produce additional diagnostics when finally
// parsed.
func (m *Meta) collectVariableValues() (map[string]backend.UnparsedVariableValue, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
ret := map[string]backend.UnparsedVariableValue{}
// First we'll deal with environment variables, since they have the lowest
// precedence.
{
env := os.Environ()
for _, raw := range env {
2019-07-18 20:19:39 +02:00
if !strings.HasPrefix(raw, VarEnvPrefix) {
continue
}
2019-07-18 20:19:39 +02:00
raw = raw[len(VarEnvPrefix):] // trim the prefix
eq := strings.Index(raw, "=")
if eq == -1 {
// Seems invalid, so we'll ignore it.
continue
}
name := raw[:eq]
rawVal := raw[eq+1:]
ret[name] = unparsedVariableValueString{
str: rawVal,
name: name,
sourceType: terraform.ValueFromEnvVar,
}
}
}
// Next up we have some implicit files that are loaded automatically
// if they are present. There's the original terraform.tfvars
// (DefaultVarsFilename) along with the later-added search for all files
// ending in .auto.tfvars.
if _, err := os.Stat(DefaultVarsFilename); err == nil {
moreDiags := m.addVarsFromFile(DefaultVarsFilename, terraform.ValueFromAutoFile, ret)
diags = diags.Append(moreDiags)
}
const defaultVarsFilenameJSON = DefaultVarsFilename + ".json"
if _, err := os.Stat(defaultVarsFilenameJSON); err == nil {
moreDiags := m.addVarsFromFile(defaultVarsFilenameJSON, terraform.ValueFromAutoFile, ret)
diags = diags.Append(moreDiags)
}
if infos, err := ioutil.ReadDir("."); err == nil {
// "infos" is already sorted by name, so we just need to filter it here.
for _, info := range infos {
name := info.Name()
if !isAutoVarFile(name) {
continue
}
moreDiags := m.addVarsFromFile(name, terraform.ValueFromAutoFile, ret)
diags = diags.Append(moreDiags)
}
}
// Finally we process values given explicitly on the command line, either
// as individual literal settings or as additional files to read.
for _, rawFlag := range m.variableArgs.AllItems() {
switch rawFlag.Name {
case "-var":
// Value should be in the form "name=value", where value is a
// raw string whose interpretation will depend on the variable's
// parsing mode.
raw := rawFlag.Value
eq := strings.Index(raw, "=")
if eq == -1 {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Invalid -var option",
fmt.Sprintf("The given -var option %q is not correctly specified. Must be a variable name and value separated by an equals sign, like -var=\"key=value\".", raw),
))
continue
}
name := raw[:eq]
rawVal := raw[eq+1:]
ret[name] = unparsedVariableValueString{
str: rawVal,
name: name,
sourceType: terraform.ValueFromCLIArg,
}
case "-var-file":
moreDiags := m.addVarsFromFile(rawFlag.Value, terraform.ValueFromNamedFile, ret)
diags = diags.Append(moreDiags)
default:
// Should never happen; always a bug in the code that built up
// the contents of m.variableArgs.
diags = diags.Append(fmt.Errorf("unsupported variable option name %q (this is a bug in Terraform)", rawFlag.Name))
}
}
return ret, diags
}
func (m *Meta) addVarsFromFile(filename string, sourceType terraform.ValueSourceType, to map[string]backend.UnparsedVariableValue) tfdiags.Diagnostics {
var diags tfdiags.Diagnostics
src, err := ioutil.ReadFile(filename)
if err != nil {
if os.IsNotExist(err) {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Failed to read variables file",
fmt.Sprintf("Given variables file %s does not exist.", filename),
))
} else {
diags = diags.Append(tfdiags.Sourceless(
tfdiags.Error,
"Failed to read variables file",
fmt.Sprintf("Error while reading %s: %s.", filename, err),
))
}
return diags
}
loader, err := m.initConfigLoader()
if err != nil {
diags = diags.Append(err)
return diags
}
// Record the file source code for snippets in diagnostic messages.
loader.Parser().ForceFileSource(filename, src)
var f *hcl.File
if strings.HasSuffix(filename, ".json") {
var hclDiags hcl.Diagnostics
f, hclDiags = hcljson.Parse(src, filename)
diags = diags.Append(hclDiags)
if f == nil || f.Body == nil {
return diags
}
} else {
var hclDiags hcl.Diagnostics
f, hclDiags = hclsyntax.ParseConfig(src, filename, hcl.Pos{Line: 1, Column: 1})
diags = diags.Append(hclDiags)
if f == nil || f.Body == nil {
return diags
}
}
// Before we do our real decode, we'll probe to see if there are any blocks
// of type "variable" in this body, since it's a common mistake for new
// users to put variable declarations in tfvars rather than variable value
// definitions, and otherwise our error message for that case is not so
// helpful.
{
content, _, _ := f.Body.PartialContent(&hcl.BodySchema{
Blocks: []hcl.BlockHeaderSchema{
{
Type: "variable",
LabelNames: []string{"name"},
},
},
})
for _, block := range content.Blocks {
name := block.Labels[0]
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Variable declaration in .tfvars file",
Detail: fmt.Sprintf("A .tfvars file is used to assign values to variables that have already been declared in .tf files, not to declare new variables. To declare variable %q, place this block in one of your .tf files, such as variables.tf.\n\nTo set a value for this variable in %s, use the definition syntax instead:\n %s = <value>", name, block.TypeRange.Filename, name),
Subject: &block.TypeRange,
})
}
if diags.HasErrors() {
// If we already found problems then JustAttributes below will find
// the same problems with less-helpful messages, so we'll bail for
// now to let the user focus on the immediate problem.
return diags
}
}
attrs, hclDiags := f.Body.JustAttributes()
diags = diags.Append(hclDiags)
for name, attr := range attrs {
to[name] = unparsedVariableValueExpression{
expr: attr.Expr,
sourceType: sourceType,
}
}
return diags
}
// unparsedVariableValueLiteral is a backend.UnparsedVariableValue
// implementation that was actually already parsed (!). This is
// intended to deal with expressions inside "tfvars" files.
type unparsedVariableValueExpression struct {
expr hcl.Expression
sourceType terraform.ValueSourceType
}
func (v unparsedVariableValueExpression) ParseVariableValue(mode configs.VariableParsingMode) (*terraform.InputValue, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
val, hclDiags := v.expr.Value(nil) // nil because no function calls or variable references are allowed here
diags = diags.Append(hclDiags)
rng := tfdiags.SourceRangeFromHCL(v.expr.Range())
return &terraform.InputValue{
Value: val,
SourceType: v.sourceType,
SourceRange: rng,
}, diags
}
// unparsedVariableValueString is a backend.UnparsedVariableValue
// implementation that parses its value from a string. This can be used
// to deal with values given directly on the command line and via environment
// variables.
type unparsedVariableValueString struct {
str string
name string
sourceType terraform.ValueSourceType
}
func (v unparsedVariableValueString) ParseVariableValue(mode configs.VariableParsingMode) (*terraform.InputValue, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
val, hclDiags := mode.Parse(v.name, v.str)
diags = diags.Append(hclDiags)
return &terraform.InputValue{
2018-10-14 16:59:15 +02:00
Value: val,
SourceType: v.sourceType,
}, diags
}