Merge pull request #12173 from hashicorp/b-remote-state-ds

providers/terraform: remote state data source supports backends
This commit is contained in:
Mitchell Hashimoto 2017-02-22 18:43:06 -08:00 committed by GitHub
commit 8f11068ab2
4 changed files with 129 additions and 40 deletions

69
backend/init/init.go Normal file
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@ -0,0 +1,69 @@
// Package init contains the list of backends that can be initialized and
// basic helper functions for initializing those backends.
package init
import (
"sync"
"github.com/hashicorp/terraform/backend"
backendlegacy "github.com/hashicorp/terraform/backend/legacy"
backendlocal "github.com/hashicorp/terraform/backend/local"
backendconsul "github.com/hashicorp/terraform/backend/remote-state/consul"
backendinmem "github.com/hashicorp/terraform/backend/remote-state/inmem"
)
// backends is the list of available backends. This is a global variable
// because backends are currently hardcoded into Terraform and can't be
// modified without recompilation.
//
// To read an available backend, use the Backend function. This ensures
// safe concurrent read access to the list of built-in backends.
//
// Backends are hardcoded into Terraform because the API for backends uses
// complex structures and supporting that over the plugin system is currently
// prohibitively difficult. For those wanting to implement a custom backend,
// they can do so with recompilation.
var backends map[string]func() backend.Backend
var backendsLock sync.Mutex
func init() {
// Our hardcoded backends. We don't need to acquire a lock here
// since init() code is serial and can't spawn goroutines.
backends = map[string]func() backend.Backend{
"local": func() backend.Backend { return &backendlocal.Local{} },
"consul": func() backend.Backend { return backendconsul.New() },
"inmem": func() backend.Backend { return backendinmem.New() },
}
// Add the legacy remote backends that haven't yet been convertd to
// the new backend API.
backendlegacy.Init(backends)
}
// Backend returns the initialization factory for the given backend, or
// nil if none exists.
func Backend(name string) func() backend.Backend {
backendsLock.Lock()
defer backendsLock.Unlock()
return backends[name]
}
// Set sets a new backend in the list of backends. If f is nil then the
// backend will be removed from the map. If this backend already exists
// then it will be overwritten.
//
// This method sets this backend globally and care should be taken to do
// this only before Terraform is executing to prevent odd behavior of backends
// changing mid-execution.
func Set(name string, f func() backend.Backend) {
backendsLock.Lock()
defer backendsLock.Unlock()
if f == nil {
delete(backends, name)
return
}
backends[name] = f
}

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@ -1,11 +1,14 @@
package terraform package terraform
import ( import (
"fmt"
"log" "log"
"time" "time"
backendinit "github.com/hashicorp/terraform/backend/init"
"github.com/hashicorp/terraform/config"
"github.com/hashicorp/terraform/helper/schema" "github.com/hashicorp/terraform/helper/schema"
"github.com/hashicorp/terraform/state/remote" "github.com/hashicorp/terraform/terraform"
) )
func dataSourceRemoteState() *schema.Resource { func dataSourceRemoteState() *schema.Resource {
@ -43,9 +46,11 @@ func dataSourceRemoteState() *schema.Resource {
func dataSourceRemoteStateRead(d *schema.ResourceData, meta interface{}) error { func dataSourceRemoteStateRead(d *schema.ResourceData, meta interface{}) error {
backend := d.Get("backend").(string) backend := d.Get("backend").(string)
config := make(map[string]string)
for k, v := range d.Get("config").(map[string]interface{}) { // Get the configuration in a type we want.
config[k] = v.(string) rawConfig, err := config.NewRawConfig(d.Get("config").(map[string]interface{}))
if err != nil {
return fmt.Errorf("error initializing backend: %s", err)
} }
// Don't break people using the old _local syntax - but note warning above // Don't break people using the old _local syntax - but note warning above
@ -55,15 +60,23 @@ func dataSourceRemoteStateRead(d *schema.ResourceData, meta interface{}) error {
} }
// Create the client to access our remote state // Create the client to access our remote state
log.Printf("[DEBUG] Initializing remote state client: %s", backend) log.Printf("[DEBUG] Initializing remote state backend: %s", backend)
client, err := remote.NewClient(backend, config) f := backendinit.Backend(backend)
if err != nil { if f == nil {
return err return fmt.Errorf("Unknown backend type: %s", backend)
}
b := f()
// Configure the backend
if err := b.Configure(terraform.NewResourceConfig(rawConfig)); err != nil {
return fmt.Errorf("error initializing backend: %s", err)
} }
// Create the remote state itself and refresh it in order to load the state // Get the state
log.Printf("[DEBUG] Loading remote state...") state, err := b.State()
state := &remote.State{Client: client} if err != nil {
return fmt.Errorf("error loading the remote state: %s", err)
}
if err := state.RefreshState(); err != nil { if err := state.RefreshState(); err != nil {
return err return err
} }

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@ -4,6 +4,7 @@ import (
"fmt" "fmt"
"testing" "testing"
backendinit "github.com/hashicorp/terraform/backend/init"
"github.com/hashicorp/terraform/helper/resource" "github.com/hashicorp/terraform/helper/resource"
"github.com/hashicorp/terraform/terraform" "github.com/hashicorp/terraform/terraform"
) )
@ -24,6 +25,25 @@ func TestState_basic(t *testing.T) {
}) })
} }
func TestState_backends(t *testing.T) {
backendinit.Set("_ds_test", backendinit.Backend("local"))
defer backendinit.Set("_ds_test", nil)
resource.UnitTest(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) },
Providers: testAccProviders,
Steps: []resource.TestStep{
{
Config: testAccState_backend,
Check: resource.ComposeTestCheckFunc(
testAccCheckStateValue(
"data.terraform_remote_state.foo", "foo", "bar"),
),
},
},
})
}
func TestState_complexOutputs(t *testing.T) { func TestState_complexOutputs(t *testing.T) {
resource.UnitTest(t, resource.TestCase{ resource.UnitTest(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) }, PreCheck: func() { testAccPreCheck(t) },
@ -72,6 +92,15 @@ data "terraform_remote_state" "foo" {
} }
}` }`
const testAccState_backend = `
data "terraform_remote_state" "foo" {
backend = "_ds_test"
config {
path = "./test-fixtures/basic.tfstate"
}
}`
const testAccState_complexOutputs = ` const testAccState_complexOutputs = `
resource "terraform_remote_state" "foo" { resource "terraform_remote_state" "foo" {
backend = "local" backend = "local"

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@ -16,6 +16,7 @@ import (
"github.com/hashicorp/go-multierror" "github.com/hashicorp/go-multierror"
"github.com/hashicorp/hcl" "github.com/hashicorp/hcl"
"github.com/hashicorp/terraform/backend" "github.com/hashicorp/terraform/backend"
backendinit "github.com/hashicorp/terraform/backend/init"
clistate "github.com/hashicorp/terraform/command/state" clistate "github.com/hashicorp/terraform/command/state"
"github.com/hashicorp/terraform/config" "github.com/hashicorp/terraform/config"
"github.com/hashicorp/terraform/state" "github.com/hashicorp/terraform/state"
@ -24,8 +25,6 @@ import (
backendlegacy "github.com/hashicorp/terraform/backend/legacy" backendlegacy "github.com/hashicorp/terraform/backend/legacy"
backendlocal "github.com/hashicorp/terraform/backend/local" backendlocal "github.com/hashicorp/terraform/backend/local"
backendconsul "github.com/hashicorp/terraform/backend/remote-state/consul"
backendinmem "github.com/hashicorp/terraform/backend/remote-state/inmem"
) )
// BackendOpts are the options used to initialize a backend.Backend. // BackendOpts are the options used to initialize a backend.Backend.
@ -1149,8 +1148,8 @@ func (m *Meta) backend_C_r_S_unchanged(
config := terraform.NewResourceConfig(rawC) config := terraform.NewResourceConfig(rawC)
// Get the backend // Get the backend
f, ok := Backends[s.Backend.Type] f := backendinit.Backend(s.Backend.Type)
if !ok { if f == nil {
return nil, fmt.Errorf(strings.TrimSpace(errBackendSavedUnknown), s.Backend.Type) return nil, fmt.Errorf(strings.TrimSpace(errBackendSavedUnknown), s.Backend.Type)
} }
b := f() b := f()
@ -1300,8 +1299,8 @@ func (m *Meta) backendInitFromConfig(c *config.Backend) (backend.Backend, error)
config := terraform.NewResourceConfig(c.RawConfig) config := terraform.NewResourceConfig(c.RawConfig)
// Get the backend // Get the backend
f, ok := Backends[c.Type] f := backendinit.Backend(c.Type)
if !ok { if f == nil {
return nil, fmt.Errorf(strings.TrimSpace(errBackendNewUnknown), c.Type) return nil, fmt.Errorf(strings.TrimSpace(errBackendNewUnknown), c.Type)
} }
b := f() b := f()
@ -1374,8 +1373,8 @@ func (m *Meta) backendInitFromSaved(s *terraform.BackendState) (backend.Backend,
config := terraform.NewResourceConfig(rawC) config := terraform.NewResourceConfig(rawC)
// Get the backend // Get the backend
f, ok := Backends[s.Type] f := backendinit.Backend(s.Type)
if !ok { if f == nil {
return nil, fmt.Errorf(strings.TrimSpace(errBackendSavedUnknown), s.Type) return nil, fmt.Errorf(strings.TrimSpace(errBackendSavedUnknown), s.Type)
} }
b := f() b := f()
@ -1397,27 +1396,6 @@ func (m *Meta) backendInitRequired(reason string) {
// Output constants and initialization code // Output constants and initialization code
//------------------------------------------------------------------- //-------------------------------------------------------------------
// Backends is the list of available backends. This is currently a hardcoded
// list that can't be modified without recompiling Terraform. This is done
// because the API for backends uses complex structures and supporting that
// over the plugin system is currently prohibitively difficult. For those
// wanting to implement a custom backend, recompilation should not be a
// high barrier.
var Backends map[string]func() backend.Backend
func init() {
// Our hardcoded backends
Backends = map[string]func() backend.Backend{
"local": func() backend.Backend { return &backendlocal.Local{} },
"consul": func() backend.Backend { return backendconsul.New() },
"inmem": func() backend.Backend { return backendinmem.New() },
}
// Add the legacy remote backends that haven't yet been convertd to
// the new backend API.
backendlegacy.Init(Backends)
}
// errBackendInitRequired is the final error message shown when reinit // errBackendInitRequired is the final error message shown when reinit
// is required for some reason. The error message includes the reason. // is required for some reason. The error message includes the reason.
var errBackendInitRequired = errors.New( var errBackendInitRequired = errors.New(