terraform/terraform/resource_address.go

473 lines
13 KiB
Go

package terraform
import (
"fmt"
"reflect"
"regexp"
"strconv"
"strings"
"github.com/hashicorp/terraform/config"
"github.com/hashicorp/terraform/config/module"
)
// ResourceAddress is a way of identifying an individual resource (or,
// eventually, a subset of resources) within the state. It is used for Targets.
type ResourceAddress struct {
// Addresses a resource falling somewhere in the module path
// When specified alone, addresses all resources within a module path
Path []string
// Addresses a specific resource that occurs in a list
Index int
InstanceType InstanceType
InstanceTypeSet bool
Name string
Type string
Mode config.ResourceMode // significant only if InstanceTypeSet
}
// Copy returns a copy of this ResourceAddress
func (r *ResourceAddress) Copy() *ResourceAddress {
if r == nil {
return nil
}
n := &ResourceAddress{
Path: make([]string, 0, len(r.Path)),
Index: r.Index,
InstanceType: r.InstanceType,
Name: r.Name,
Type: r.Type,
Mode: r.Mode,
}
n.Path = append(n.Path, r.Path...)
return n
}
// String outputs the address that parses into this address.
func (r *ResourceAddress) String() string {
var result []string
for _, p := range r.Path {
result = append(result, "module", p)
}
switch r.Mode {
case config.ManagedResourceMode:
// nothing to do
case config.DataResourceMode:
result = append(result, "data")
default:
panic(fmt.Errorf("unsupported resource mode %s", r.Mode))
}
if r.Type != "" {
result = append(result, r.Type)
}
if r.Name != "" {
name := r.Name
if r.InstanceTypeSet {
switch r.InstanceType {
case TypePrimary:
name += ".primary"
case TypeDeposed:
name += ".deposed"
case TypeTainted:
name += ".tainted"
}
}
if r.Index >= 0 {
name += fmt.Sprintf("[%d]", r.Index)
}
result = append(result, name)
}
return strings.Join(result, ".")
}
// HasResourceSpec returns true if the address has a resource spec, as
// defined in the documentation:
// https://www.terraform.io/docs/internals/resource-addressing.html
// In particular, this returns false if the address contains only
// a module path, thus addressing the entire module.
func (r *ResourceAddress) HasResourceSpec() bool {
return r.Type != "" && r.Name != ""
}
// WholeModuleAddress returns the resource address that refers to all
// resources in the same module as the receiver address.
func (r *ResourceAddress) WholeModuleAddress() *ResourceAddress {
return &ResourceAddress{
Path: r.Path,
Index: -1,
InstanceTypeSet: false,
}
}
// MatchesConfig returns true if the receiver matches the given
// configuration resource within the given configuration module.
//
// Since resource configuration blocks represent all of the instances of
// a multi-instance resource, the index of the address (if any) is not
// considered.
func (r *ResourceAddress) MatchesConfig(mod *module.Tree, rc *config.Resource) bool {
if r.HasResourceSpec() {
if r.Mode != rc.Mode || r.Type != rc.Type || r.Name != rc.Name {
return false
}
}
addrPath := r.Path
cfgPath := mod.Path()
// normalize
if len(addrPath) == 0 {
addrPath = nil
}
if len(cfgPath) == 0 {
cfgPath = nil
}
return reflect.DeepEqual(addrPath, cfgPath)
}
// stateId returns the ID that this resource should be entered with
// in the state. This is also used for diffs. In the future, we'd like to
// move away from this string field so I don't export this.
func (r *ResourceAddress) stateId() string {
result := fmt.Sprintf("%s.%s", r.Type, r.Name)
switch r.Mode {
case config.ManagedResourceMode:
// Done
case config.DataResourceMode:
result = fmt.Sprintf("data.%s", result)
default:
panic(fmt.Errorf("unknown resource mode: %s", r.Mode))
}
if r.Index >= 0 {
result += fmt.Sprintf(".%d", r.Index)
}
return result
}
// parseResourceAddressConfig creates a resource address from a config.Resource
func parseResourceAddressConfig(r *config.Resource) (*ResourceAddress, error) {
return &ResourceAddress{
Type: r.Type,
Name: r.Name,
Index: -1,
InstanceType: TypePrimary,
Mode: r.Mode,
}, nil
}
// parseResourceAddressInternal parses the somewhat bespoke resource
// identifier used in states and diffs, such as "instance.name.0".
func parseResourceAddressInternal(s string) (*ResourceAddress, error) {
// Split based on ".". Every resource address should have at least two
// elements (type and name).
parts := strings.Split(s, ".")
if len(parts) < 2 || len(parts) > 4 {
return nil, fmt.Errorf("Invalid internal resource address format: %s", s)
}
// Data resource if we have at least 3 parts and the first one is data
mode := config.ManagedResourceMode
if len(parts) > 2 && parts[0] == "data" {
mode = config.DataResourceMode
parts = parts[1:]
}
// If we're not a data resource and we have more than 3, then it is an error
if len(parts) > 3 && mode != config.DataResourceMode {
return nil, fmt.Errorf("Invalid internal resource address format: %s", s)
}
// Build the parts of the resource address that are guaranteed to exist
addr := &ResourceAddress{
Type: parts[0],
Name: parts[1],
Index: -1,
InstanceType: TypePrimary,
Mode: mode,
}
// If we have more parts, then we have an index. Parse that.
if len(parts) > 2 {
idx, err := strconv.ParseInt(parts[2], 0, 0)
if err != nil {
return nil, fmt.Errorf("Error parsing resource address %q: %s", s, err)
}
addr.Index = int(idx)
}
return addr, nil
}
func ParseResourceAddress(s string) (*ResourceAddress, error) {
matches, err := tokenizeResourceAddress(s)
if err != nil {
return nil, err
}
mode := config.ManagedResourceMode
if matches["data_prefix"] != "" {
mode = config.DataResourceMode
}
resourceIndex, err := ParseResourceIndex(matches["index"])
if err != nil {
return nil, err
}
instanceType, err := ParseInstanceType(matches["instance_type"])
if err != nil {
return nil, err
}
path := ParseResourcePath(matches["path"])
// not allowed to say "data." without a type following
if mode == config.DataResourceMode && matches["type"] == "" {
return nil, fmt.Errorf(
"invalid resource address %q: must target specific data instance",
s,
)
}
return &ResourceAddress{
Path: path,
Index: resourceIndex,
InstanceType: instanceType,
InstanceTypeSet: matches["instance_type"] != "",
Name: matches["name"],
Type: matches["type"],
Mode: mode,
}, nil
}
// ParseResourceAddressForInstanceDiff creates a ResourceAddress for a
// resource name as described in a module diff.
//
// For historical reasons a different addressing format is used in this
// context. The internal format should not be shown in the UI and instead
// this function should be used to translate to a ResourceAddress and
// then, where appropriate, use the String method to produce a canonical
// resource address string for display in the UI.
//
// The given path slice must be empty (or nil) for the root module, and
// otherwise consist of a sequence of module names traversing down into
// the module tree. If a non-nil path is provided, the caller must not
// modify its underlying array after passing it to this function.
func ParseResourceAddressForInstanceDiff(path []string, key string) (*ResourceAddress, error) {
addr, err := parseResourceAddressInternal(key)
if err != nil {
return nil, err
}
addr.Path = path
return addr, nil
}
// Contains returns true if and only if the given node is contained within
// the receiver.
//
// Containment is defined in terms of the module and resource heirarchy:
// a resource is contained within its module and any ancestor modules,
// an indexed resource instance is contained with the unindexed resource, etc.
func (addr *ResourceAddress) Contains(other *ResourceAddress) bool {
ourPath := addr.Path
givenPath := other.Path
if len(givenPath) < len(ourPath) {
return false
}
for i := range ourPath {
if ourPath[i] != givenPath[i] {
return false
}
}
// If the receiver is a whole-module address then the path prefix
// matching is all we need.
if !addr.HasResourceSpec() {
return true
}
if addr.Type != other.Type || addr.Name != other.Name || addr.Mode != other.Mode {
return false
}
if addr.Index != -1 && addr.Index != other.Index {
return false
}
if addr.InstanceTypeSet && (addr.InstanceTypeSet != other.InstanceTypeSet || addr.InstanceType != other.InstanceType) {
return false
}
return true
}
// Equals returns true if the receiver matches the given address.
//
// The name of this method is a misnomer, since it doesn't test for exact
// equality. Instead, it tests that the _specified_ parts of each
// address match, treating any unspecified parts as wildcards.
//
// See also Contains, which takes a more heirarchical approach to comparing
// addresses.
func (addr *ResourceAddress) Equals(raw interface{}) bool {
other, ok := raw.(*ResourceAddress)
if !ok {
return false
}
pathMatch := len(addr.Path) == 0 && len(other.Path) == 0 ||
reflect.DeepEqual(addr.Path, other.Path)
indexMatch := addr.Index == -1 ||
other.Index == -1 ||
addr.Index == other.Index
nameMatch := addr.Name == "" ||
other.Name == "" ||
addr.Name == other.Name
typeMatch := addr.Type == "" ||
other.Type == "" ||
addr.Type == other.Type
// mode is significant only when type is set
modeMatch := addr.Type == "" ||
other.Type == "" ||
addr.Mode == other.Mode
return pathMatch &&
indexMatch &&
addr.InstanceType == other.InstanceType &&
nameMatch &&
typeMatch &&
modeMatch
}
// Less returns true if and only if the receiver should be sorted before
// the given address when presenting a list of resource addresses to
// an end-user.
//
// This sort uses lexicographic sorting for most components, but uses
// numeric sort for indices, thus causing index 10 to sort after
// index 9, rather than after index 1.
func (addr *ResourceAddress) Less(other *ResourceAddress) bool {
switch {
case len(addr.Path) != len(other.Path):
return len(addr.Path) < len(other.Path)
case !reflect.DeepEqual(addr.Path, other.Path):
// If the two paths are the same length but don't match, we'll just
// cheat and compare the string forms since it's easier than
// comparing all of the path segments in turn, and lexicographic
// comparison is correct for the module path portion.
addrStr := addr.String()
otherStr := other.String()
return addrStr < otherStr
case addr.Mode != other.Mode:
return addr.Mode == config.DataResourceMode
case addr.Type != other.Type:
return addr.Type < other.Type
case addr.Name != other.Name:
return addr.Name < other.Name
case addr.Index != other.Index:
// Since "Index" is -1 for an un-indexed address, this also conveniently
// sorts unindexed addresses before indexed ones, should they both
// appear for some reason.
return addr.Index < other.Index
case addr.InstanceTypeSet != other.InstanceTypeSet:
return !addr.InstanceTypeSet
case addr.InstanceType != other.InstanceType:
// InstanceType is actually an enum, so this is just an arbitrary
// sort based on the enum numeric values, and thus not particularly
// meaningful.
return addr.InstanceType < other.InstanceType
default:
return false
}
}
func ParseResourceIndex(s string) (int, error) {
if s == "" {
return -1, nil
}
return strconv.Atoi(s)
}
func ParseResourcePath(s string) []string {
if s == "" {
return nil
}
parts := strings.Split(s, ".")
path := make([]string, 0, len(parts))
for _, s := range parts {
// Due to the limitations of the regexp match below, the path match has
// some noise in it we have to filter out :|
if s == "" || s == "module" {
continue
}
path = append(path, s)
}
return path
}
func ParseInstanceType(s string) (InstanceType, error) {
switch s {
case "", "primary":
return TypePrimary, nil
case "deposed":
return TypeDeposed, nil
case "tainted":
return TypeTainted, nil
default:
return TypeInvalid, fmt.Errorf("Unexpected value for InstanceType field: %q", s)
}
}
func tokenizeResourceAddress(s string) (map[string]string, error) {
// Example of portions of the regexp below using the
// string "aws_instance.web.tainted[1]"
re := regexp.MustCompile(`\A` +
// "module.foo.module.bar" (optional)
`(?P<path>(?:module\.(?P<module_name>[^.]+)\.?)*)` +
// possibly "data.", if targeting is a data resource
`(?P<data_prefix>(?:data\.)?)` +
// "aws_instance.web" (optional when module path specified)
`(?:(?P<type>[^.]+)\.(?P<name>[^.[]+))?` +
// "tainted" (optional, omission implies: "primary")
`(?:\.(?P<instance_type>\w+))?` +
// "1" (optional, omission implies: "0")
`(?:\[(?P<index>\d+)\])?` +
`\z`)
groupNames := re.SubexpNames()
rawMatches := re.FindAllStringSubmatch(s, -1)
if len(rawMatches) != 1 {
return nil, fmt.Errorf("invalid resource address %q", s)
}
matches := make(map[string]string)
for i, m := range rawMatches[0] {
matches[groupNames[i]] = m
}
return matches, nil
}