From e4e972db6778610c9570beafa14a4440ef9ed0c2 Mon Sep 17 00:00:00 2001
From: Martin Atkins <mart@degeneration.co.uk>
Date: Tue, 8 May 2018 10:01:43 -0700
Subject: [PATCH] core: Fix MissingProviderTransformer matching existing
 providers

In the change to using addrs types rather than string keys directly here
I incorrectly made this use the _relative_ provider config instead of
the absolute one, causing MissingProviderTransformer to only match
providers defined in the root module (due to ambiguity in the string
representations of these address types).

The rest of this change is improved logging and test output that helped
with debugging this issue.
---
 terraform/transform_provider.go      | 26 ++++++++++++++++++++------
 terraform/transform_provider_test.go |  2 +-
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/terraform/transform_provider.go b/terraform/transform_provider.go
index 6816d4ab19..53dd017329 100644
--- a/terraform/transform_provider.go
+++ b/terraform/transform_provider.go
@@ -81,6 +81,11 @@ func (t *ProviderTransformer) Transform(g *Graph) error {
 	for _, v := range g.Vertices() {
 		if pv, ok := v.(GraphNodeProviderConsumer); ok {
 			p, exact := pv.ProvidedBy()
+			if exact {
+				log.Printf("[TRACE] ProviderTransformer: %s is provided by %s exactly", dag.VertexName(v), p)
+			} else {
+				log.Printf("[TRACE] ProviderTransformer: %s is provided by %s or inherited equivalent", dag.VertexName(v), p)
+			}
 
 			key := p.String()
 			target := m[key]
@@ -92,15 +97,21 @@ func (t *ProviderTransformer) Transform(g *Graph) error {
 				break
 			}
 
+			if target != nil {
+				log.Printf("[TRACE] ProviderTransformer: exact match for %s providing %s", p, dag.VertexName(v))
+			}
+
 			// if we don't have a provider at this level, walk up the path looking for one,
 			// unless we were told to be exact.
-			if !exact {
+			if target == nil && !exact {
 				for pp, ok := p.Inherited(); ok; pp, ok = pp.Inherited() {
 					key := pp.String()
 					target = m[key]
 					if target != nil {
+						log.Printf("[TRACE] ProviderTransformer: %s uses inherited configuration %s", dag.VertexName(v), pp)
 						break
 					}
+					log.Printf("[TRACE] ProviderTransformer: looking for %s to provide %s", pp, dag.VertexName(v))
 				}
 			}
 
@@ -119,7 +130,7 @@ func (t *ProviderTransformer) Transform(g *Graph) error {
 				key = target.(GraphNodeProvider).ProviderAddr().String()
 			}
 
-			log.Printf("[DEBUG] %s handled by %s", dag.VertexName(pv), key)
+			log.Printf("[DEBUG] %s provided by %s", dag.VertexName(pv), key)
 			pv.SetProvider(target.ProviderAddr())
 			g.Connect(dag.BasicEdge(v, target))
 		}
@@ -199,8 +210,7 @@ func (t *MissingProviderTransformer) Transform(g *Graph) error {
 		}
 
 		p, _ := pv.ProvidedBy()
-		configAddr := p.ProviderConfig
-		key := configAddr.String()
+		key := p.String()
 		provider := m[key]
 
 		// we already have it
@@ -209,7 +219,7 @@ func (t *MissingProviderTransformer) Transform(g *Graph) error {
 		}
 
 		// we don't implicitly create aliased providers
-		if configAddr.Alias != "" {
+		if p.ProviderConfig.Alias != "" {
 			log.Println("[DEBUG] not adding implicit aliased config for", p.String())
 			continue
 		}
@@ -380,6 +390,10 @@ type graphNodeProxyProvider struct {
 	target GraphNodeProvider
 }
 
+var (
+	_ GraphNodeProvider = (*graphNodeProxyProvider)(nil)
+)
+
 func (n *graphNodeProxyProvider) ProviderAddr() addrs.AbsProviderConfig {
 	return n.addr
 }
@@ -389,7 +403,7 @@ func (n *graphNodeProxyProvider) Path() addrs.ModuleInstance {
 }
 
 func (n *graphNodeProxyProvider) Name() string {
-	return n.addr.String()
+	return n.addr.String() + " (proxy)"
 }
 
 // find the concrete provider instance
diff --git a/terraform/transform_provider_test.go b/terraform/transform_provider_test.go
index 939d8de987..7661bb9a85 100644
--- a/terraform/transform_provider_test.go
+++ b/terraform/transform_provider_test.go
@@ -583,7 +583,7 @@ func TestProviderConfigTransformer_implicitModule(t *testing.T) {
   provider.aws.foo
 provider.aws.foo`)
 	if actual != expected {
-		t.Fatalf("expected:\n%s\n\ngot:\n%s", expected, actual)
+		t.Fatalf("wrong result\n\nexpected:\n%s\n\ngot:\n%s", expected, actual)
 	}
 }