terraform/helper/config/validator.go

192 lines
4.2 KiB
Go

package config
import (
"fmt"
"strconv"
"strings"
"github.com/hashicorp/terraform/flatmap"
"github.com/hashicorp/terraform/terraform"
)
// Validator is a helper that helps you validate the configuration
// of your resource, resource provider, etc.
//
// At the most basic level, set the Required and Optional lists to be
// specifiers of keys that are required or optional. If a key shows up
// that isn't in one of these two lists, then an error is generated.
//
// The "specifiers" allowed in this is a fairly rich syntax to help
// describe the format of your configuration:
//
// * Basic keys are just strings. For example: "foo" will match the
// "foo" key.
//
// * Nested structure keys can be matched by doing
// "listener.*.foo". This will verify that there is at least one
// listener element that has the "foo" key set.
//
// * The existence of a nested structure can be checked by simply
// doing "listener.*" which will verify that there is at least
// one element in the "listener" structure. This is NOT
// validating that "listener" is an array. It is validating
// that it is a nested structure in the configuration.
//
type Validator struct {
Required []string
Optional []string
}
func (v *Validator) Validate(
c *terraform.ResourceConfig) (ws []string, es []error) {
// Flatten the configuration so it is easier to reason about
flat := flatmap.Flatten(c.Raw)
keySet := make(map[string]validatorKey)
for i, vs := range [][]string{v.Required, v.Optional} {
req := i == 0
for _, k := range vs {
vk, err := newValidatorKey(k, req)
if err != nil {
es = append(es, err)
continue
}
keySet[k] = vk
}
}
purged := make([]string, 0)
for _, kv := range keySet {
p, w, e := kv.Validate(flat)
if len(w) > 0 {
ws = append(ws, w...)
}
if len(e) > 0 {
es = append(es, e...)
}
purged = append(purged, p...)
}
// Delete all the keys we processed in order to find
// the unknown keys.
for _, p := range purged {
delete(flat, p)
}
// The rest are unknown
for k, _ := range flat {
es = append(es, fmt.Errorf("Unknown configuration: %s", k))
}
return
}
type validatorKey interface {
Validate(map[string]string) ([]string, []string, []error)
}
func newValidatorKey(k string, req bool) (validatorKey, error) {
var result validatorKey
parts := strings.Split(k, ".")
if len(parts) > 1 && parts[1] == "*" {
key := ""
if len(parts) >= 3 {
key = parts[2]
}
result = &nestedValidatorKey{
Prefix: parts[0],
Key: key,
Required: req,
}
} else {
result = &basicValidatorKey{
Key: k,
Required: req,
}
}
return result, nil
}
// basicValidatorKey validates keys that are basic such as "foo"
type basicValidatorKey struct {
Key string
Required bool
}
func (v *basicValidatorKey) Validate(
m map[string]string) ([]string, []string, []error) {
for k, _ := range m {
// If we have the exact key its a match
if k == v.Key {
return []string{k}, nil, nil
}
}
if !v.Required {
return nil, nil, nil
}
return nil, nil, []error{fmt.Errorf(
"Key not found: %s", v.Key)}
}
type nestedValidatorKey struct {
Prefix string
Key string
Required bool
}
func (v *nestedValidatorKey) Validate(
m map[string]string) ([]string, []string, []error) {
countStr, ok := m[v.Prefix+".#"]
if !ok {
if !v.Required || v.Key != "" {
// Not present, that is okay
return nil, nil, nil
} else {
// Required and isn't present
return nil, nil, []error{fmt.Errorf(
"Key not found: %s", v.Prefix)}
}
}
count, err := strconv.ParseInt(countStr, 0, 0)
if err != nil {
// This shouldn't happen if flatmap works properly
panic("invalid flatmap array")
}
var errs []error
used := make([]string, 1, count+1)
used[0] = v.Prefix + ".#"
for i := 0; i < int(count); i++ {
prefix := fmt.Sprintf("%s.%d.", v.Prefix, i)
if v.Key != "" {
key := prefix + v.Key
if _, ok := m[key]; !ok {
errs = append(errs, fmt.Errorf(
"%s[%d]: does not contain required key %s",
v.Prefix,
i,
v.Key))
}
}
for k, _ := range m {
if !strings.HasPrefix(k, prefix) {
continue
}
used = append(used, k)
}
}
return used, nil, errs
}