opentofu/terraform/state.go
2015-02-23 13:50:53 -08:00

1019 lines
23 KiB
Go

package terraform
import (
"bufio"
"bytes"
"encoding/json"
"fmt"
"io"
"log"
"reflect"
"sort"
"strings"
"github.com/hashicorp/terraform/config"
)
const (
// StateVersion is the current version for our state file
StateVersion = 1
)
// rootModulePath is the path of the root module
var rootModulePath = []string{"root"}
// State keeps track of a snapshot state-of-the-world that Terraform
// can use to keep track of what real world resources it is actually
// managing. This is the latest format as of Terraform 0.3
type State struct {
// Version is the protocol version. Currently only "1".
Version int `json:"version"`
// Serial is incremented on any operation that modifies
// the State file. It is used to detect potentially conflicting
// updates.
Serial int64 `json:"serial"`
// Remote is used to track the metadata required to
// pull and push state files from a remote storage endpoint.
Remote *RemoteState `json:"remote,omitempty"`
// Modules contains all the modules in a breadth-first order
Modules []*ModuleState `json:"modules"`
}
// NewState is used to initialize a blank state
func NewState() *State {
s := &State{}
s.init()
return s
}
// Children returns the ModuleStates that are direct children of
// the given path. If the path is "root", for example, then children
// returned might be "root.child", but not "root.child.grandchild".
func (s *State) Children(path []string) []*ModuleState {
// TODO: test
result := make([]*ModuleState, 0)
for _, m := range s.Modules {
if len(m.Path) != len(path)+1 {
continue
}
if !reflect.DeepEqual(path, m.Path[:len(path)]) {
continue
}
result = append(result, m)
}
return result
}
// AddModule adds the module with the given path to the state.
//
// This should be the preferred method to add module states since it
// allows us to optimize lookups later as well as control sorting.
func (s *State) AddModule(path []string) *ModuleState {
m := &ModuleState{Path: path}
m.init()
s.Modules = append(s.Modules, m)
s.sort()
return m
}
// ModuleByPath is used to lookup the module state for the given path.
// This should be the prefered lookup mechanism as it allows for future
// lookup optimizations.
func (s *State) ModuleByPath(path []string) *ModuleState {
if s == nil {
return nil
}
for _, mod := range s.Modules {
if mod.Path == nil {
panic("missing module path")
}
if reflect.DeepEqual(mod.Path, path) {
return mod
}
}
return nil
}
// ModuleOrphans returns all the module orphans in this state by
// returning their full paths. These paths can be used with ModuleByPath
// to return the actual state.
func (s *State) ModuleOrphans(path []string, c *config.Config) [][]string {
childrenKeys := make(map[string]struct{})
if c != nil {
for _, m := range c.Modules {
childrenKeys[m.Name] = struct{}{}
}
}
// Go over the direct children and find any that aren't in our
// keys.
var orphans [][]string
for _, m := range s.Children(path) {
if _, ok := childrenKeys[m.Path[len(m.Path)-1]]; ok {
continue
}
orphans = append(orphans, m.Path)
}
return orphans
}
// RootModule returns the ModuleState for the root module
func (s *State) RootModule() *ModuleState {
root := s.ModuleByPath(rootModulePath)
if root == nil {
panic("missing root module")
}
return root
}
// Equal tests if one state is equal to another.
func (s *State) Equal(other *State) bool {
// If the versions are different, they're certainly not equal
if s.Version != other.Version {
return false
}
// If any of the modules are not equal, then this state isn't equal
for _, m := range s.Modules {
// This isn't very optimal currently but works.
otherM := other.ModuleByPath(m.Path)
if otherM == nil {
return false
}
// If they're not equal, then we're not equal!
if !m.Equal(otherM) {
return false
}
}
return true
}
func (s *State) init() {
if s.Version == 0 {
s.Version = StateVersion
}
if len(s.Modules) == 0 {
root := &ModuleState{
Path: rootModulePath,
}
root.init()
s.Modules = []*ModuleState{root}
}
}
func (s *State) deepcopy() *State {
if s == nil {
return nil
}
n := &State{
Version: s.Version,
Serial: s.Serial,
Modules: make([]*ModuleState, 0, len(s.Modules)),
}
for _, mod := range s.Modules {
n.Modules = append(n.Modules, mod.deepcopy())
}
if s.Remote != nil {
n.Remote = s.Remote.deepcopy()
}
return n
}
// prune is used to remove any resources that are no longer required
func (s *State) prune() {
if s == nil {
return
}
for _, mod := range s.Modules {
mod.prune()
}
if s.Remote != nil && s.Remote.Empty() {
s.Remote = nil
}
}
// sort sorts the modules
func (s *State) sort() {
sort.Sort(moduleStateSort(s.Modules))
// Allow modules to be sorted
for _, m := range s.Modules {
m.sort()
}
}
func (s *State) GoString() string {
return fmt.Sprintf("*%#v", *s)
}
func (s *State) String() string {
var buf bytes.Buffer
for _, m := range s.Modules {
mStr := m.String()
// If we're the root module, we just write the output directly.
if reflect.DeepEqual(m.Path, rootModulePath) {
buf.WriteString(mStr + "\n")
continue
}
buf.WriteString(fmt.Sprintf("module.%s:\n", strings.Join(m.Path[1:], ".")))
s := bufio.NewScanner(strings.NewReader(mStr))
for s.Scan() {
text := s.Text()
if text != "" {
text = " " + text
}
buf.WriteString(fmt.Sprintf("%s\n", text))
}
}
return strings.TrimSpace(buf.String())
}
// RemoteState is used to track the information about a remote
// state store that we push/pull state to.
type RemoteState struct {
// Type controls the client we use for the remote state
Type string `json:"type"`
// Config is used to store arbitrary configuration that
// is type specific
Config map[string]string `json:"config"`
}
func (r *RemoteState) deepcopy() *RemoteState {
confCopy := make(map[string]string, len(r.Config))
for k, v := range r.Config {
confCopy[k] = v
}
return &RemoteState{
Type: r.Type,
Config: confCopy,
}
}
func (r *RemoteState) Empty() bool {
return r.Type == "" && len(r.Config) == 0
}
func (r *RemoteState) Equals(other *RemoteState) bool {
if r.Type != other.Type {
return false
}
if len(r.Config) != len(other.Config) {
return false
}
for k, v := range r.Config {
if other.Config[k] != v {
return false
}
}
return true
}
// ModuleState is used to track all the state relevant to a single
// module. Previous to Terraform 0.3, all state belonged to the "root"
// module.
type ModuleState struct {
// Path is the import path from the root module. Modules imports are
// always disjoint, so the path represents amodule tree
Path []string `json:"path"`
// Outputs declared by the module and maintained for each module
// even though only the root module technically needs to be kept.
// This allows operators to inspect values at the boundaries.
Outputs map[string]string `json:"outputs"`
// Resources is a mapping of the logically named resource to
// the state of the resource. Each resource may actually have
// N instances underneath, although a user only needs to think
// about the 1:1 case.
Resources map[string]*ResourceState `json:"resources"`
// Dependencies are a list of things that this module relies on
// existing to remain intact. For example: an module may depend
// on a VPC ID given by an aws_vpc resource.
//
// Terraform uses this information to build valid destruction
// orders and to warn the user if they're destroying a module that
// another resource depends on.
//
// Things can be put into this list that may not be managed by
// Terraform. If Terraform doesn't find a matching ID in the
// overall state, then it assumes it isn't managed and doesn't
// worry about it.
Dependencies []string `json:"depends_on,omitempty"`
}
// Equal tests whether one module state is equal to another.
func (m *ModuleState) Equal(other *ModuleState) bool {
// Paths must be equal
if !reflect.DeepEqual(m.Path, other.Path) {
return false
}
// Outputs must be equal
if len(m.Outputs) != len(other.Outputs) {
return false
}
for k, v := range m.Outputs {
if other.Outputs[k] != v {
return false
}
}
// Dependencies must be equal. This sorts these in place but
// this shouldn't cause any problems.
sort.Strings(m.Dependencies)
sort.Strings(other.Dependencies)
if len(m.Dependencies) != len(other.Dependencies) {
return false
}
for i, d := range m.Dependencies {
if other.Dependencies[i] != d {
return false
}
}
// Resources must be equal
if len(m.Resources) != len(other.Resources) {
return false
}
for k, r := range m.Resources {
otherR, ok := other.Resources[k]
if !ok {
return false
}
if !r.Equal(otherR) {
return false
}
}
return true
}
// IsRoot says whether or not this module diff is for the root module.
func (m *ModuleState) IsRoot() bool {
return reflect.DeepEqual(m.Path, rootModulePath)
}
// Orphans returns a list of keys of resources that are in the State
// but aren't present in the configuration itself. Hence, these keys
// represent the state of resources that are orphans.
func (m *ModuleState) Orphans(c *config.Config) []string {
keys := make(map[string]struct{})
for k, _ := range m.Resources {
keys[k] = struct{}{}
}
if c != nil {
for _, r := range c.Resources {
delete(keys, r.Id())
for k, _ := range keys {
if strings.HasPrefix(k, r.Id()+".") {
delete(keys, k)
}
}
}
}
result := make([]string, 0, len(keys))
for k, _ := range keys {
result = append(result, k)
}
return result
}
// View returns a view with the given resource prefix.
func (m *ModuleState) View(id string) *ModuleState {
if m == nil {
return m
}
r := m.deepcopy()
for k, _ := range r.Resources {
if id == k || strings.HasPrefix(k, id+".") {
continue
}
delete(r.Resources, k)
}
return r
}
func (m *ModuleState) init() {
if m.Outputs == nil {
m.Outputs = make(map[string]string)
}
if m.Resources == nil {
m.Resources = make(map[string]*ResourceState)
}
}
func (m *ModuleState) deepcopy() *ModuleState {
if m == nil {
return nil
}
n := &ModuleState{
Path: make([]string, len(m.Path)),
Outputs: make(map[string]string, len(m.Outputs)),
Resources: make(map[string]*ResourceState, len(m.Resources)),
}
copy(n.Path, m.Path)
for k, v := range m.Outputs {
n.Outputs[k] = v
}
for k, v := range m.Resources {
n.Resources[k] = v.deepcopy()
}
return n
}
// prune is used to remove any resources that are no longer required
func (m *ModuleState) prune() {
for k, v := range m.Resources {
v.prune()
if (v.Primary == nil || v.Primary.ID == "") && len(v.Tainted) == 0 {
delete(m.Resources, k)
}
}
for k, v := range m.Outputs {
if v == config.UnknownVariableValue {
delete(m.Outputs, k)
}
}
}
func (m *ModuleState) sort() {
for _, v := range m.Resources {
v.sort()
}
}
func (m *ModuleState) GoString() string {
return fmt.Sprintf("*%#v", *m)
}
func (m *ModuleState) String() string {
var buf bytes.Buffer
if len(m.Resources) == 0 {
buf.WriteString("<no state>")
}
names := make([]string, 0, len(m.Resources))
for name, _ := range m.Resources {
names = append(names, name)
}
sort.Strings(names)
for _, k := range names {
rs := m.Resources[k]
var id string
if rs.Primary != nil {
id = rs.Primary.ID
}
if id == "" {
id = "<not created>"
}
taintStr := ""
if len(rs.Tainted) > 0 {
taintStr = fmt.Sprintf(" (%d tainted)", len(rs.Tainted))
}
buf.WriteString(fmt.Sprintf("%s:%s\n", k, taintStr))
buf.WriteString(fmt.Sprintf(" ID = %s\n", id))
var attributes map[string]string
if rs.Primary != nil {
attributes = rs.Primary.Attributes
}
attrKeys := make([]string, 0, len(attributes))
for ak, _ := range attributes {
if ak == "id" {
continue
}
attrKeys = append(attrKeys, ak)
}
sort.Strings(attrKeys)
for _, ak := range attrKeys {
av := attributes[ak]
buf.WriteString(fmt.Sprintf(" %s = %s\n", ak, av))
}
for idx, t := range rs.Tainted {
buf.WriteString(fmt.Sprintf(" Tainted ID %d = %s\n", idx+1, t.ID))
}
if len(rs.Dependencies) > 0 {
buf.WriteString(fmt.Sprintf("\n Dependencies:\n"))
for _, dep := range rs.Dependencies {
buf.WriteString(fmt.Sprintf(" %s\n", dep))
}
}
}
if len(m.Outputs) > 0 {
buf.WriteString("\nOutputs:\n\n")
ks := make([]string, 0, len(m.Outputs))
for k, _ := range m.Outputs {
ks = append(ks, k)
}
sort.Strings(ks)
for _, k := range ks {
v := m.Outputs[k]
buf.WriteString(fmt.Sprintf("%s = %s\n", k, v))
}
}
return buf.String()
}
// ResourceState holds the state of a resource that is used so that
// a provider can find and manage an existing resource as well as for
// storing attributes that are used to populate variables of child
// resources.
//
// Attributes has attributes about the created resource that are
// queryable in interpolation: "${type.id.attr}"
//
// Extra is just extra data that a provider can return that we store
// for later, but is not exposed in any way to the user.
//
type ResourceState struct {
// This is filled in and managed by Terraform, and is the resource
// type itself such as "mycloud_instance". If a resource provider sets
// this value, it won't be persisted.
Type string `json:"type"`
// Dependencies are a list of things that this resource relies on
// existing to remain intact. For example: an AWS instance might
// depend on a subnet (which itself might depend on a VPC, and so
// on).
//
// Terraform uses this information to build valid destruction
// orders and to warn the user if they're destroying a resource that
// another resource depends on.
//
// Things can be put into this list that may not be managed by
// Terraform. If Terraform doesn't find a matching ID in the
// overall state, then it assumes it isn't managed and doesn't
// worry about it.
Dependencies []string `json:"depends_on,omitempty"`
// Primary is the current active instance for this resource.
// It can be replaced but only after a successful creation.
// This is the instances on which providers will act.
Primary *InstanceState `json:"primary"`
// Tainted is used to track any underlying instances that
// have been created but are in a bad or unknown state and
// need to be cleaned up subsequently. In the
// standard case, there is only at most a single instance.
// However, in pathological cases, it is possible for the number
// of instances to accumulate.
Tainted []*InstanceState `json:"tainted,omitempty"`
}
// Equal tests whether two ResourceStates are equal.
func (s *ResourceState) Equal(other *ResourceState) bool {
if s.Type != other.Type {
return false
}
// Dependencies must be equal
sort.Strings(s.Dependencies)
sort.Strings(other.Dependencies)
if len(s.Dependencies) != len(other.Dependencies) {
return false
}
for i, d := range s.Dependencies {
if other.Dependencies[i] != d {
return false
}
}
// States must be equal
if !s.Primary.Equal(other.Primary) {
return false
}
// Tainted
taints := make(map[string]*InstanceState)
for _, t := range other.Tainted {
if t == nil {
continue
}
taints[t.ID] = t
}
for _, t := range s.Tainted {
if t == nil {
continue
}
otherT, ok := taints[t.ID]
if !ok {
return false
}
delete(taints, t.ID)
if !t.Equal(otherT) {
return false
}
}
// This means that we have stuff in other tainted that we don't
// have, so it is not equal.
if len(taints) > 0 {
return false
}
return true
}
func (r *ResourceState) init() {
if r.Primary == nil {
r.Primary = &InstanceState{}
}
r.Primary.init()
}
func (r *ResourceState) deepcopy() *ResourceState {
if r == nil {
return nil
}
n := &ResourceState{
Type: r.Type,
Dependencies: make([]string, len(r.Dependencies)),
Primary: r.Primary.deepcopy(),
Tainted: make([]*InstanceState, 0, len(r.Tainted)),
}
copy(n.Dependencies, r.Dependencies)
for _, inst := range r.Tainted {
n.Tainted = append(n.Tainted, inst.deepcopy())
}
return n
}
// prune is used to remove any instances that are no longer required
func (r *ResourceState) prune() {
n := len(r.Tainted)
for i := 0; i < n; i++ {
inst := r.Tainted[i]
if inst == nil || inst.ID == "" {
copy(r.Tainted[i:], r.Tainted[i+1:])
r.Tainted[n-1] = nil
n--
i--
}
}
r.Tainted = r.Tainted[:n]
}
func (r *ResourceState) sort() {
sort.Strings(r.Dependencies)
}
func (s *ResourceState) GoString() string {
return fmt.Sprintf("*%#v", *s)
}
func (s *ResourceState) String() string {
var buf bytes.Buffer
buf.WriteString(fmt.Sprintf("Type = %s", s.Type))
return buf.String()
}
// InstanceState is used to track the unique state information belonging
// to a given instance.
type InstanceState struct {
// A unique ID for this resource. This is opaque to Terraform
// and is only meant as a lookup mechanism for the providers.
ID string `json:"id"`
// Attributes are basic information about the resource. Any keys here
// are accessible in variable format within Terraform configurations:
// ${resourcetype.name.attribute}.
Attributes map[string]string `json:"attributes,omitempty"`
// Ephemeral is used to store any state associated with this instance
// that is necessary for the Terraform run to complete, but is not
// persisted to a state file.
Ephemeral EphemeralState `json:"-"`
}
func (i *InstanceState) init() {
if i.Attributes == nil {
i.Attributes = make(map[string]string)
}
i.Ephemeral.init()
}
func (i *InstanceState) deepcopy() *InstanceState {
if i == nil {
return nil
}
n := &InstanceState{
ID: i.ID,
Ephemeral: *i.Ephemeral.deepcopy(),
}
if i.Attributes != nil {
n.Attributes = make(map[string]string, len(i.Attributes))
for k, v := range i.Attributes {
n.Attributes[k] = v
}
}
return n
}
func (s *InstanceState) Equal(other *InstanceState) bool {
// Short circuit some nil checks
if s == nil || other == nil {
return s == other
}
// IDs must be equal
if s.ID != other.ID {
return false
}
// Attributes must be equal
if len(s.Attributes) != len(other.Attributes) {
return false
}
for k, v := range s.Attributes {
otherV, ok := other.Attributes[k]
if !ok {
return false
}
if v != otherV {
return false
}
}
return true
}
// MergeDiff takes a ResourceDiff and merges the attributes into
// this resource state in order to generate a new state. This new
// state can be used to provide updated attribute lookups for
// variable interpolation.
//
// If the diff attribute requires computing the value, and hence
// won't be available until apply, the value is replaced with the
// computeID.
func (s *InstanceState) MergeDiff(d *InstanceDiff) *InstanceState {
result := s.deepcopy()
if result == nil {
result = new(InstanceState)
}
result.init()
if s != nil {
for k, v := range s.Attributes {
result.Attributes[k] = v
}
}
if d != nil {
for k, diff := range d.Attributes {
if diff.NewRemoved {
delete(result.Attributes, k)
continue
}
if diff.NewComputed {
result.Attributes[k] = config.UnknownVariableValue
continue
}
result.Attributes[k] = diff.New
}
}
return result
}
func (i *InstanceState) GoString() string {
return fmt.Sprintf("*%#v", *i)
}
func (i *InstanceState) String() string {
var buf bytes.Buffer
if i == nil || i.ID == "" {
return "<not created>"
}
buf.WriteString(fmt.Sprintf("ID = %s\n", i.ID))
attributes := i.Attributes
attrKeys := make([]string, 0, len(attributes))
for ak, _ := range attributes {
if ak == "id" {
continue
}
attrKeys = append(attrKeys, ak)
}
sort.Strings(attrKeys)
for _, ak := range attrKeys {
av := attributes[ak]
buf.WriteString(fmt.Sprintf("%s = %s\n", ak, av))
}
return buf.String()
}
// EphemeralState is used for transient state that is only kept in-memory
type EphemeralState struct {
// ConnInfo is used for the providers to export information which is
// used to connect to the resource for provisioning. For example,
// this could contain SSH or WinRM credentials.
ConnInfo map[string]string `json:"-"`
}
func (e *EphemeralState) init() {
if e.ConnInfo == nil {
e.ConnInfo = make(map[string]string)
}
}
func (e *EphemeralState) deepcopy() *EphemeralState {
if e == nil {
return nil
}
n := &EphemeralState{}
if e.ConnInfo != nil {
n.ConnInfo = make(map[string]string, len(e.ConnInfo))
for k, v := range e.ConnInfo {
n.ConnInfo[k] = v
}
}
return n
}
// ReadState reads a state structure out of a reader in the format that
// was written by WriteState.
func ReadState(src io.Reader) (*State, error) {
buf := bufio.NewReader(src)
// Check if this is a V1 format
start, err := buf.Peek(len(stateFormatMagic))
if err != nil {
return nil, fmt.Errorf("Failed to check for magic bytes: %v", err)
}
if string(start) == stateFormatMagic {
// Read the old state
old, err := ReadStateV1(buf)
if err != nil {
return nil, err
}
return upgradeV1State(old)
}
// Otherwise, must be V2
dec := json.NewDecoder(buf)
state := &State{}
if err := dec.Decode(state); err != nil {
return nil, fmt.Errorf("Decoding state file failed: %v", err)
}
// Check the version, this to ensure we don't read a future
// version that we don't understand
if state.Version > StateVersion {
return nil, fmt.Errorf("State version %d not supported, please update.",
state.Version)
}
// Sort it
state.sort()
return state, nil
}
// WriteState writes a state somewhere in a binary format.
func WriteState(d *State, dst io.Writer) error {
// Make sure it is sorted
d.sort()
// Ensure the version is set
d.Version = StateVersion
// Always increment the serial number
d.Serial++
// Encode the data in a human-friendly way
data, err := json.MarshalIndent(d, "", " ")
if err != nil {
return fmt.Errorf("Failed to encode state: %s", err)
}
// We append a newline to the data because MarshalIndent doesn't
data = append(data, '\n')
// Write the data out to the dst
if _, err := io.Copy(dst, bytes.NewReader(data)); err != nil {
return fmt.Errorf("Failed to write state: %v", err)
}
return nil
}
// upgradeV1State is used to upgrade a V1 state representation
// into a proper State representation.
func upgradeV1State(old *StateV1) (*State, error) {
s := &State{}
s.init()
// Old format had no modules, so we migrate everything
// directly into the root module.
root := s.RootModule()
// Copy the outputs
root.Outputs = old.Outputs
// Upgrade the resources
for id, rs := range old.Resources {
newRs := &ResourceState{
Type: rs.Type,
}
root.Resources[id] = newRs
// Migrate to an instance state
instance := &InstanceState{
ID: rs.ID,
Attributes: rs.Attributes,
}
// Check if this is the primary or tainted instance
if _, ok := old.Tainted[id]; ok {
newRs.Tainted = append(newRs.Tainted, instance)
} else {
newRs.Primary = instance
}
// Warn if the resource uses Extra, as there is
// no upgrade path for this! Now totally deprecated.
if len(rs.Extra) > 0 {
log.Printf(
"[WARN] Resource %s uses deprecated attribute "+
"storage, state file upgrade may be incomplete.",
rs.ID,
)
}
}
return s, nil
}
// moduleStateSort implements sort.Interface to sort module states
type moduleStateSort []*ModuleState
func (s moduleStateSort) Len() int {
return len(s)
}
func (s moduleStateSort) Less(i, j int) bool {
a := s[i]
b := s[j]
// If the lengths are different, then the shorter one always wins
if len(a.Path) != len(b.Path) {
return len(a.Path) < len(b.Path)
}
// Otherwise, compare by last path element
idx := len(a.Path) - 1
return a.Path[idx] < b.Path[idx]
}
func (s moduleStateSort) Swap(i, j int) {
s[i], s[j] = s[j], s[i]
}