From 157d166c512e078676a6a326adb5182be81fd7bb Mon Sep 17 00:00:00 2001
From: Quinn Slack <qslack@qslack.com>
Date: Sat, 19 Jan 2019 22:30:21 -1000
Subject: [PATCH] pass path to VersionedFileSystems for impls that have
 multiple underlying VFSes

---
 cmd/docsite/site.go | 6 +++---
 fs_test.go          | 2 +-
 handler.go          | 4 ++--
 site.go             | 6 +++---
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/cmd/docsite/site.go b/cmd/docsite/site.go
index 1845280..2c74b7f 100644
--- a/cmd/docsite/site.go
+++ b/cmd/docsite/site.go
@@ -103,7 +103,7 @@ func openDocsiteFromConfig(configData []byte, baseDir string) (*docsite.Site, *d
 
 type nonVersionedFileSystem struct{ http.FileSystem }
 
-func (fs nonVersionedFileSystem) OpenVersion(_ context.Context, version string) (http.FileSystem, error) {
+func (fs nonVersionedFileSystem) OpenVersion(_ context.Context, version, path string) (http.FileSystem, error) {
 	if version != "" {
 		return nil, errors.New("content versioning is not supported")
 	}
@@ -137,7 +137,7 @@ func openDocsiteFromEnv() (*docsite.Site, *docsiteConfig, error) {
 	content := &versionedFileSystemURL{url: config.Content}
 	// Prefetch content at its default version. This ensures that the program exits if the content
 	// default version is unavailable.
-	if _, err := content.OpenVersion(context.Background(), ""); err != nil {
+	if _, err := content.OpenVersion(context.Background(), "", "/"); err != nil {
 		return nil, nil, errors.WithMessage(err, "downloading content default version")
 	}
 
@@ -166,7 +166,7 @@ type fileSystemCacheEntry struct {
 
 const fileSystemCacheTTL = 5 * time.Minute
 
-func (fs *versionedFileSystemURL) OpenVersion(ctx context.Context, version string) (http.FileSystem, error) {
+func (fs *versionedFileSystemURL) OpenVersion(ctx context.Context, version, path string) (http.FileSystem, error) {
 	// HACK(sqs): this works for codeload.github.com
 	if version == "" {
 		version = "HEAD"
diff --git a/fs_test.go b/fs_test.go
index de02992..1735496 100644
--- a/fs_test.go
+++ b/fs_test.go
@@ -42,7 +42,7 @@ func TestWalkFileSystem(t *testing.T) {
 
 type versionedFileSystem map[string]http.FileSystem
 
-func (vfs versionedFileSystem) OpenVersion(_ context.Context, version string) (http.FileSystem, error) {
+func (vfs versionedFileSystem) OpenVersion(_ context.Context, version, path string) (http.FileSystem, error) {
 	fs, ok := vfs[version]
 	if !ok {
 		return nil, &os.PathError{Op: "OpenVersion", Path: version, Err: os.ErrNotExist}
diff --git a/handler.go b/handler.go
index 4019a46..288b55a 100644
--- a/handler.go
+++ b/handler.go
@@ -53,7 +53,7 @@ func (s *Site) Handler() http.Handler {
 
 		if IsContentAsset(r.URL.Path) {
 			// Serve non-Markdown content files (such as images) using http.FileServer.
-			content, err := s.Content.OpenVersion(r.Context(), contentVersion)
+			content, err := s.Content.OpenVersion(r.Context(), contentVersion, r.URL.Path)
 			if err != nil {
 				w.Header().Set("Cache-Control", "max-age=0")
 				if os.IsNotExist(err) {
@@ -72,7 +72,7 @@ func (s *Site) Handler() http.Handler {
 			ContentVersion:  contentVersion,
 			ContentPagePath: r.URL.Path,
 		}
-		content, err := s.Content.OpenVersion(r.Context(), contentVersion)
+		content, err := s.Content.OpenVersion(r.Context(), contentVersion, r.URL.Path)
 		if err != nil {
 			// Version not found.
 			if !os.IsNotExist(err) {
diff --git a/site.go b/site.go
index e907cad..55eab50 100644
--- a/site.go
+++ b/site.go
@@ -17,7 +17,7 @@ import (
 
 // VersionedFileSystem represents multiple versions of an http.FileSystem.
 type VersionedFileSystem interface {
-	OpenVersion(ctx context.Context, version string) (http.FileSystem, error)
+	OpenVersion(ctx context.Context, version, path string) (http.FileSystem, error)
 }
 
 // Site represents a documentation site, including all of its templates, assets, and content.
@@ -81,7 +81,7 @@ func (s *Site) newContentPage(filePath string, data []byte, contentVersion strin
 
 // AllContentPages returns a list of all content pages in the site.
 func (s *Site) AllContentPages(ctx context.Context, contentVersion string) ([]*ContentPage, error) {
-	content, err := s.Content.OpenVersion(ctx, contentVersion)
+	content, err := s.Content.OpenVersion(ctx, contentVersion, "/")
 	if err != nil {
 		return nil, err
 	}
@@ -110,7 +110,7 @@ func (s *Site) AllContentPages(ctx context.Context, contentVersion string) ([]*C
 // If the resulting ContentPage differs from the path argument, the caller should (if possible)
 // communicate a redirect.
 func (s *Site) ResolveContentPage(ctx context.Context, contentVersion, path string) (*ContentPage, error) {
-	content, err := s.Content.OpenVersion(ctx, contentVersion)
+	content, err := s.Content.OpenVersion(ctx, contentVersion, path)
 	if err != nil {
 		return nil, err
 	}