Refactor to reduce vfs -> terraformWriter dependency

upup/pkg/fi/cloudup/terraformWriter/writer.go

@@ -94,7 +94,7 @@ func (t *TerraformWriter) AddFileBytes(resourceType string, resourceName string,
 	return LiteralFunctionExpression(fn, path), nil
 }
 
-func (t *TerraformWriter) EnsureTerraformProvider(tfProvider *TerraformProvider) {
+func (t *TerraformWriter) EnsureTerraformProvider(name string, arguments map[string]string) *TerraformProvider {
 	t.mutex.Lock()
 	defer t.mutex.Unlock()
 
@@ -102,17 +102,23 @@ func (t *TerraformWriter) EnsureTerraformProvider(tfProvider *TerraformProvider)
 		t.Providers = make(map[string]*TerraformProvider)
 	}
 
+	tfProvider := &TerraformProvider{
+		Name:      name,
+		Arguments: arguments,
+	}
+
 	key := tfProvider.Name
 
 	existing := t.Providers[key]
 	if existing != nil {
 		if reflect.DeepEqual(tfProvider, existing) {
 			// already exists and matches
-			return
+			return existing
 		}
 		klog.Fatalf("attempt to add different tfProvider with key %q", key)
 	}
 	t.Providers[key] = tfProvider
+	return tfProvider
 }
 
 func (t *TerraformWriter) AddFilePath(resourceType string, resourceName string, key string, data []byte, base64 bool) (*Literal, error) {

util/pkg/vfs/gsfs.go

@@ -119,15 +119,6 @@ func (p *GSPath) String() string {
 	return p.Path()
 }
 
-// TerraformProvider returns the provider name and necessary arguments
-func (p *GSPath) TerraformProvider() (*terraformWriter.TerraformProvider, error) {
-	provider := &terraformWriter.TerraformProvider{
-		Name:      "google",
-		Arguments: map[string]string{}, // GCS doesn't need the project and region specified
-	}
-	return provider, nil
-}
-
 func (p *GSPath) Remove() error {
 	ctx := context.TODO()
 	done, err := RetryWithBackoff(gcsWriteBackoff, func() (bool, error) {
@@ -434,11 +425,8 @@ func (p *GSPath) RenderTerraform(w *terraformWriter.TerraformWriter, name string
 		return fmt.Errorf("reading data: %v", err)
 	}
 
-	tfProvider, err := p.TerraformProvider()
-	if err != nil {
-		return err
-	}
-	w.EnsureTerraformProvider(tfProvider)
+	tfProviderArguments := map[string]string{} // GCS doesn't need the project and region specified
+	w.EnsureTerraformProvider("google", tfProviderArguments)
 
 	content, err := w.AddFilePath("google_storage_bucket_object", name, "content", bytes, false)
 	if err != nil {

util/pkg/vfs/memfs.go

@@ -211,17 +211,6 @@ func (p *MemFSPath) IsPublic() (bool, error) {
 	return isPublic, nil
 }
 
-// Terraform support for integration tests.
-
-func (p *MemFSPath) TerraformProvider() (*terraformWriter.TerraformProvider, error) {
-	return &terraformWriter.TerraformProvider{
-		Name: "aws",
-		Arguments: map[string]string{
-			"region": "us-test-1",
-		},
-	}, nil
-}
-
 type terraformMemFSFile struct {
 	Bucket   string                   `json:"bucket" cty:"bucket"`
 	Key      string                   `json:"key" cty:"key"`
@@ -237,11 +226,10 @@ func (p *MemFSPath) RenderTerraform(w *terraformWriter.TerraformWriter, name str
 		return fmt.Errorf("reading data: %v", err)
 	}
 
-	tfProvider, err := p.TerraformProvider()
-	if err != nil {
-		return err
+	tfProviderArguments := map[string]string{
+		"region": "us-test-1",
 	}
-	w.EnsureTerraformProvider(tfProvider)
+	w.EnsureTerraformProvider("aws", tfProviderArguments)
 
 	content, err := w.AddFileBytes("aws_s3_object", name, "content", bytes, false)
 	if err != nil {

util/pkg/vfs/s3fs.go

@@ -89,24 +89,6 @@ func (p *S3Path) String() string {
 	return p.Path()
 }
 
-// TerraformProvider returns the provider name and necessary arguments
-func (p *S3Path) TerraformProvider() (*terraformWriter.TerraformProvider, error) {
-	ctx := context.TODO()
-
-	bucketDetails, err := p.getBucketDetails(ctx)
-	if err != nil {
-		return nil, err
-	}
-
-	provider := &terraformWriter.TerraformProvider{
-		Name: "aws",
-		Arguments: map[string]string{
-			"region": bucketDetails.region,
-		},
-	}
-	return provider, nil
-}
-
 func (p *S3Path) Remove() error {
 	ctx := context.TODO()
 
@@ -605,11 +587,15 @@ func (p *S3Path) RenderTerraform(w *terraformWriter.TerraformWriter, name string
 		return fmt.Errorf("reading data: %v", err)
 	}
 
-	tfProvider, err := p.TerraformProvider()
+	bucketDetails, err := p.getBucketDetails(ctx)
 	if err != nil {
 		return err
 	}
-	w.EnsureTerraformProvider(tfProvider)
+
+	tfProviderArguments := map[string]string{
+		"region": bucketDetails.region,
+	}
+	w.EnsureTerraformProvider("aws", tfProviderArguments)
 
 	content, err := w.AddFileBytes("aws_s3_object", name, "content", bytes, false)
 	if err != nil {

util/pkg/vfs/vfs.go

@@ -79,9 +79,6 @@ type TerraformPath interface {
 	Path
 	// RenderTerraform renders the file to a TerraformWriter.
 	RenderTerraform(writer *terraformWriter.TerraformWriter, name string, data io.Reader, acl ACL) error
-
-	// TerraformProvider returns provider information
-	TerraformProvider() (*terraformWriter.TerraformProvider, error)
 }
 
 type HasHash interface {