terraform/helper/schema/set.go

251 lines
5.2 KiB
Go

package schema
import (
"bytes"
"fmt"
"reflect"
"sort"
"strconv"
"sync"
"github.com/hashicorp/terraform/helper/hashcode"
)
// HashString hashes strings. If you want a Set of strings, this is the
// SchemaSetFunc you want.
func HashString(v interface{}) int {
return hashcode.String(v.(string))
}
// HashInt hashes integers. If you want a Set of integers, this is the
// SchemaSetFunc you want.
func HashInt(v interface{}) int {
return hashcode.String(strconv.Itoa(v.(int)))
}
// HashResource hashes complex structures that are described using
// a *Resource. This is the default set implementation used when a set's
// element type is a full resource.
func HashResource(resource *Resource) SchemaSetFunc {
return func(v interface{}) int {
var buf bytes.Buffer
SerializeResourceForHash(&buf, v, resource)
return hashcode.String(buf.String())
}
}
// HashSchema hashes values that are described using a *Schema. This is the
// default set implementation used when a set's element type is a single
// schema.
func HashSchema(schema *Schema) SchemaSetFunc {
return func(v interface{}) int {
var buf bytes.Buffer
SerializeValueForHash(&buf, v, schema)
return hashcode.String(buf.String())
}
}
// Set is a set data structure that is returned for elements of type
// TypeSet.
type Set struct {
F SchemaSetFunc
m map[string]interface{}
once sync.Once
}
// NewSet is a convenience method for creating a new set with the given
// items.
func NewSet(f SchemaSetFunc, items []interface{}) *Set {
s := &Set{F: f}
for _, i := range items {
s.Add(i)
}
return s
}
// CopySet returns a copy of another set.
func CopySet(otherSet *Set) *Set {
return NewSet(otherSet.F, otherSet.List())
}
// Add adds an item to the set if it isn't already in the set.
func (s *Set) Add(item interface{}) {
s.add(item, false)
}
// Remove removes an item if it's already in the set. Idempotent.
func (s *Set) Remove(item interface{}) {
s.remove(item)
}
// Contains checks if the set has the given item.
func (s *Set) Contains(item interface{}) bool {
_, ok := s.m[s.hash(item)]
return ok
}
// Len returns the amount of items in the set.
func (s *Set) Len() int {
return len(s.m)
}
// List returns the elements of this set in slice format.
//
// The order of the returned elements is deterministic. Given the same
// set, the order of this will always be the same.
func (s *Set) List() []interface{} {
result := make([]interface{}, len(s.m))
for i, k := range s.listCode() {
result[i] = s.m[k]
}
return result
}
// Difference performs a set difference of the two sets, returning
// a new third set that has only the elements unique to this set.
func (s *Set) Difference(other *Set) *Set {
result := &Set{F: s.F}
result.once.Do(result.init)
for k, v := range s.m {
if _, ok := other.m[k]; !ok {
result.m[k] = v
}
}
return result
}
// Intersection performs the set intersection of the two sets
// and returns a new third set.
func (s *Set) Intersection(other *Set) *Set {
result := &Set{F: s.F}
result.once.Do(result.init)
for k, v := range s.m {
if _, ok := other.m[k]; ok {
result.m[k] = v
}
}
return result
}
// Union performs the set union of the two sets and returns a new third
// set.
func (s *Set) Union(other *Set) *Set {
result := &Set{F: s.F}
result.once.Do(result.init)
for k, v := range s.m {
result.m[k] = v
}
for k, v := range other.m {
result.m[k] = v
}
return result
}
func (s *Set) Equal(raw interface{}) bool {
other, ok := raw.(*Set)
if !ok {
return false
}
return reflect.DeepEqual(s.m, other.m)
}
// HashEqual simply checks to the keys the top-level map to the keys in the
// other set's top-level map to see if they are equal. This obviously assumes
// you have a properly working hash function - use HashResource if in doubt.
func (s *Set) HashEqual(raw interface{}) bool {
other, ok := raw.(*Set)
if !ok {
return false
}
ks1 := make([]string, 0)
ks2 := make([]string, 0)
for k := range s.m {
ks1 = append(ks1, k)
}
for k := range other.m {
ks2 = append(ks2, k)
}
sort.Strings(ks1)
sort.Strings(ks2)
return reflect.DeepEqual(ks1, ks2)
}
func (s *Set) GoString() string {
return fmt.Sprintf("*Set(%#v)", s.m)
}
func (s *Set) init() {
s.m = make(map[string]interface{})
}
func (s *Set) add(item interface{}, computed bool) string {
s.once.Do(s.init)
code := s.hash(item)
if computed {
code = "~" + code
if isProto5() {
tmpCode := code
count := 0
for _, exists := s.m[tmpCode]; exists; _, exists = s.m[tmpCode] {
count++
tmpCode = fmt.Sprintf("%s%d", code, count)
}
code = tmpCode
}
}
if _, ok := s.m[code]; !ok {
s.m[code] = item
}
return code
}
func (s *Set) hash(item interface{}) string {
code := s.F(item)
// Always return a nonnegative hashcode.
if code < 0 {
code = -code
}
return strconv.Itoa(code)
}
func (s *Set) remove(item interface{}) string {
s.once.Do(s.init)
code := s.hash(item)
delete(s.m, code)
return code
}
func (s *Set) index(item interface{}) int {
return sort.SearchStrings(s.listCode(), s.hash(item))
}
func (s *Set) listCode() []string {
// Sort the hash codes so the order of the list is deterministic
keys := make([]string, 0, len(s.m))
for k := range s.m {
keys = append(keys, k)
}
sort.Sort(sort.StringSlice(keys))
return keys
}