From a614f6105a993934dbf0b3cab97a7a7fd408a877 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 12 Feb 2015 19:34:21 -0800
Subject: [PATCH] terraform: apply starting

---
 terraform/context.go            | 17 ++++---
 terraform/context_test.go       |  1 -
 terraform/eval_apply.go         | 81 +++++++++++++++++++++++++++++++++
 terraform/graph_walk_context.go |  9 +---
 4 files changed, 93 insertions(+), 15 deletions(-)
 create mode 100644 terraform/eval_apply.go

diff --git a/terraform/context.go b/terraform/context.go
index df83b0689..7dfbdbc5d 100644
--- a/terraform/context.go
+++ b/terraform/context.go
@@ -27,6 +27,7 @@ type ContextOpts struct {
 // NewContext. See the documentation for that.
 type Context2 struct {
 	diff         *Diff
+	diffLock     sync.RWMutex
 	hooks        []Hook
 	module       *module.Tree
 	providers    map[string]ResourceProviderFactory
@@ -134,17 +135,19 @@ func (c *Context2) Plan(opts *PlanOpts) (*Plan, error) {
 		operation = walkPlan
 	}
 
+	// Setup our diff
+	c.diffLock.Lock()
+	c.diff = new(Diff)
+	c.diff.init()
+	c.diffLock.Unlock()
+
 	// Do the walk
-	walker, err := c.walk(operation)
-	if err != nil {
+	if _, err := c.walk(operation); err != nil {
 		return nil, err
 	}
-	p.Diff = walker.Diff
+	p.Diff = c.diff
 
-	// Update the diff so that our context is up-to-date
-	c.diff = p.Diff
-
-	return p, err
+	return p, nil
 }
 
 // Refresh goes through all the resources in the state and refreshes them
diff --git a/terraform/context_test.go b/terraform/context_test.go
index 5948489a9..1ff312def 100644
--- a/terraform/context_test.go
+++ b/terraform/context_test.go
@@ -2673,7 +2673,6 @@ func TestContextInput_varOnly(t *testing.T) {
 }
 */
 
-/*
 func TestContext2Apply(t *testing.T) {
 	m := testModule(t, "apply-good")
 	p := testProvider("aws")
diff --git a/terraform/eval_apply.go b/terraform/eval_apply.go
new file mode 100644
index 000000000..032150f1e
--- /dev/null
+++ b/terraform/eval_apply.go
@@ -0,0 +1,81 @@
+package terraform
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/hashicorp/go-multierror"
+	"github.com/hashicorp/terraform/config"
+)
+
+// EvalApply is an EvalNode implementation that writes the diff to
+// the full diff.
+type EvalApply struct {
+	Info     *InstanceInfo
+	State    **InstanceState
+	Diff     **InstanceDiff
+	Provider *ResourceProvider
+	Output   **InstanceState
+}
+
+func (n *EvalApply) Args() ([]EvalNode, []EvalType) {
+	return nil, nil
+}
+
+// TODO: test
+func (n *EvalApply) Eval(
+	ctx EvalContext, args []interface{}) (interface{}, error) {
+	diff := *n.Diff
+	provider := *n.Provider
+	state := *n.State
+
+	// If we have no diff, we have nothing to do!
+	if diff.Empty() {
+		log.Printf(
+			"[DEBUG] apply: %s: diff is empty, doing nothing.", n.Info.Id)
+		return nil, nil
+	}
+
+	// Remove any output values from the diff
+	for k, ad := range diff.Attributes {
+		if ad.Type == DiffAttrOutput {
+			delete(diff.Attributes, k)
+		}
+	}
+
+	// TODO: hooks
+
+	// With the completed diff, apply!
+	log.Printf("[DEBUG] apply: %s: executing Apply", n.Info.Id)
+	state, err := provider.Apply(n.Info, state, diff)
+	if state == nil {
+		state = new(InstanceState)
+	}
+	state.init()
+
+	// Force the "id" attribute to be our ID
+	if state.ID != "" {
+		state.Attributes["id"] = state.ID
+	}
+
+	// If the value is the unknown variable value, then it is an error.
+	// In this case we record the error and remove it from the state
+	for ak, av := range state.Attributes {
+		if av == config.UnknownVariableValue {
+			err = multierror.Append(err, fmt.Errorf(
+				"Attribute with unknown value: %s", ak))
+			delete(state.Attributes, ak)
+		}
+	}
+
+	// Write the final state
+	if n.Output != nil {
+		*n.Output = state
+	}
+
+	return nil, nil
+}
+
+func (n *EvalApply) Type() EvalType {
+	return EvalTypeNull
+}
diff --git a/terraform/graph_walk_context.go b/terraform/graph_walk_context.go
index f8cc81086..3517cc3fd 100644
--- a/terraform/graph_walk_context.go
+++ b/terraform/graph_walk_context.go
@@ -17,13 +17,11 @@ type ContextGraphWalker struct {
 
 	// Outputs, do not set these. Do not read these while the graph
 	// is being walked.
-	Diff               *Diff
 	ValidationWarnings []string
 	ValidationErrors   []error
 
 	errorLock           sync.Mutex
 	once                sync.Once
-	diffLock            sync.RWMutex
 	contexts            map[string]*BuiltinEvalContext
 	contextLock         sync.Mutex
 	providerCache       map[string]ResourceProvider
@@ -64,8 +62,8 @@ func (w *ContextGraphWalker) EnterGraph(g *Graph) EvalContext {
 		Provisioners:        w.Context.provisioners,
 		ProvisionerCache:    w.provisionerCache,
 		ProvisionerLock:     &w.provisionerLock,
-		DiffValue:           w.Diff,
-		DiffLock:            &w.diffLock,
+		DiffValue:           w.Context.diff,
+		DiffLock:            &w.Context.diffLock,
 		StateValue:          w.Context.state,
 		StateLock:           &w.Context.stateLock,
 		Interpolater: &Interpolater{
@@ -111,9 +109,6 @@ func (w *ContextGraphWalker) ExitEvalTree(
 }
 
 func (w *ContextGraphWalker) init() {
-	w.Diff = new(Diff)
-	w.Diff.init()
-
 	w.contexts = make(map[string]*BuiltinEvalContext, 5)
 	w.providerCache = make(map[string]ResourceProvider, 5)
 	w.providerConfigCache = make(map[string]*ResourceConfig, 5)