1 files changed, 29 insertions, 8 deletions

diff --git a/internal/web/server.go b/internal/web/server.go
index 483663e..a7af06b 100644
--- a/internal/web/server.go
+++ b/internal/web/server.go
@@ -66,9 +66,10 @@ func hostname(h string) string {
 type ctxKey int
 
 const (
-	ctxUser    ctxKey = iota
-	ctxBlog           // the blog a handler operates on (public page, or /b/{sub}/ management)
-	ctxHostSub        // subdomain derived from the Host header
+	ctxUser      ctxKey = iota
+	ctxBlog             // the blog a handler operates on (public page, or /b/{sub}/ management)
+	ctxBlogStore        // that blog's store, bound to its own database
+	ctxHostSub          // subdomain derived from the Host header
 )
 
 func currentUser(r *http.Request) *store.User {
@@ -81,13 +82,33 @@ func currentBlog(r *http.Request) *store.Blog {
 	return b
 }
 
+// blogStore is the store of the blog in the context; only valid behind hostBlog or withBlog.
+func blogStore(r *http.Request) *store.BlogStore {
+	bs, _ := r.Context().Value(ctxBlogStore).(*store.BlogStore)
+	return bs
+}
+
 // ---- middleware ----------------------------------------------------------
 
+// resolveBlog looks a subdomain up in the registry and opens its database.
+func (s *Server) resolveBlog(r *http.Request, sub string) (*http.Request, error) {
+	blog, err := s.st.BlogBySubdomain(r.Context(), sub)
+	if err != nil {
+		return r, err
+	}
+	bs, err := s.st.Open(r.Context(), blog)
+	if err != nil {
+		return r, err
+	}
+	ctx := context.WithValue(r.Context(), ctxBlog, blog)
+	return r.WithContext(context.WithValue(ctx, ctxBlogStore, bs)), nil
+}
+
 // hostBlog resolves the blog named by the Host header into the context for public pages.
 func (s *Server) hostBlog(next http.HandlerFunc) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		sub, _ := r.Context().Value(ctxHostSub).(string)
-		blog, err := s.st.BlogBySubdomain(r.Context(), sub)
+		r, err := s.resolveBlog(r, sub)
 		if err != nil {
 			if errors.Is(err, store.ErrNotFound) {
 				s.plainError(w, http.StatusNotFound, "No blog here (yet).")
@@ -96,7 +117,7 @@ func (s *Server) hostBlog(next http.HandlerFunc) http.HandlerFunc {
 			s.serverError(w, err)
 			return
 		}
-		next(w, r.WithContext(context.WithValue(r.Context(), ctxBlog, blog)))
+		next(w, r)
 	}
 }
 
@@ -176,7 +197,7 @@ func (s *Server) requireAdmin(next http.HandlerFunc) http.HandlerFunc {
 func (s *Server) withBlog(next http.HandlerFunc) http.HandlerFunc {
 	return s.requireAuth(func(w http.ResponseWriter, r *http.Request) {
 		u := currentUser(r)
-		blog, err := s.st.BlogBySubdomain(r.Context(), r.PathValue("sub"))
+		r, err := s.resolveBlog(r, r.PathValue("sub"))
 		if err != nil {
 			if errors.Is(err, store.ErrNotFound) {
 				http.NotFound(w, r)
@@ -185,11 +206,11 @@ func (s *Server) withBlog(next http.HandlerFunc) http.HandlerFunc {
 			s.serverError(w, err)
 			return
 		}
-		if blog.OwnerID != u.ID && !u.IsSuperadmin() {
+		if blog := currentBlog(r); blog.OwnerID != u.ID && !u.IsSuperadmin() {
 			s.plainError(w, http.StatusForbidden, "This is not your blog.")
 			return
 		}
-		next(w, r.WithContext(context.WithValue(r.Context(), ctxBlog, blog)))
+		next(w, r)
 	})
 }