Container makes /var/lib/pixa usable before starting pixad (closes #159)

The entrypoint now creates /var/lib/pixa if it is missing. When the
directory or one of its top-level entries belongs to another user or
group, it gives the whole tree to pixad (uid and gid 65532); it then
sets the directory's mode to 750 and runs the server as pixad as
before. Data left by a run under another uid is taken over this way.
Only the top level is checked, so a normal start does not walk the
cache; the tree is changed deepest first, so an interrupted start is
finished by the next one.

"Running under upaas" in README.md no longer tells the operator to
create or chown the host directory.

Model: opus-5-5

README.md

@@ -238,7 +238,7 @@ variables set by the file's `env:` section are checked the same way.
 | `PIXA_UPSTREAM_FETCH_TIMEOUT`        | `upstream_fetch_timeout`        | Time allowed for one fetch from an upstream host; default `30s`              |
 | `PIXA_UPSTREAM_MAX_RESPONSE_SIZE`    | `upstream_max_response_size`    | Largest upstream response accepted, in bytes; default 50 MiB                 |
 | `PIXA_DOWNSTREAM_TIMEOUT`            | `downstream_timeout`            | Time allowed for answering one client request; default `60s`                 |
-| `PIXA_ACCESS_CONTROL_ALLOW_ORIGIN`   | `access_control_allow_origin`   | CORS origin allowed to read image responses: `*` or one origin; default `*`  |
+| `PIXA_ACCESS_CONTROL_ALLOW_ORIGIN`   | `access_control_allow_origin`   | CORS origin allowed to read responses: `*` or one origin; default `*`        |
 | `PIXA_METRICS_USERNAME`              | `metrics.username`              | Username for `/metrics`, which is served only when both are set              |
 | `PIXA_METRICS_PASSWORD`              | `metrics.password`              | Password for `/metrics`; set together with the username                      |
 | `PIXA_SENTRY_DSN`                    | `sentry_dsn`                    | Sentry DSN for error reporting; empty disables it                            |
@@ -247,9 +247,8 @@ variables set by the file's `env:` section are checked the same way.
 
 Key settings in more detail:
 
-- `access_control_allow_origin` — the origin a browser lets read the responses
-  of the image routes, `/v1/image/` and `/v1/e/`, sent as the CORS
-  `Access-Control-Allow-Origin` header; no other route sends it. `*`, the
+- `access_control_allow_origin` — the origin a browser lets read pixa's
+  responses, sent as the CORS `Access-Control-Allow-Origin` header: `*`, the
   default, is any site; otherwise one `http` or `https` origin such as
   `https://example.com`, whose host is a lowercase host name (letters,
   digits, hyphens and dots, with a letter in its last part) or an IP address

TODO.md

@@ -29,12 +29,6 @@ P2: security: referer blacklist
 
 # Completed Steps
 
-- 2026-09-29 only the image routes send CORS headers (closes #98): the CORS
-  middleware, with the `access_control_allow_origin` origin, moved from the
-  router root onto a `/v1` subrouter holding `/v1/image/` and `/v1/e/`, where it
-  still answers a preflight `OPTIONS` request; the login and URL generator
-  pages, `/metrics` and the other routes send no `Access-Control-Allow-Origin`;
-  documented in `README.md` and `config.example.yml`.
 - 2026-09-29 the container makes `/var/lib/pixa` usable by itself (closes
   #159): `deploy/docker-entrypoint.sh` creates the directory if it is missing,
   gives the directory and everything in it to `pixad` when the directory or one

config.example.yml

@@ -103,9 +103,8 @@ upstream_max_response_size: 52428800
 # longer than upstream_fetch_timeout plus 20 seconds.
 downstream_timeout: 60s
 
-# The origin a browser lets read the responses of the image routes,
-# /v1/image/ and /v1/e/, sent as the CORS Access-Control-Allow-Origin
-# header; no other route sends it. "*" (the default) is any site;
+# The origin a browser lets read pixa's responses, sent as the CORS
+# Access-Control-Allow-Origin header: "*" (the default) is any site;
 # otherwise one http or https origin such as https://example.com, whose
 # host is a lowercase host name (letters, digits, hyphens and dots, with a
 # letter in its last part) or an IP address (IPv6 in brackets, in its

internal/server/cors_internal_test.go

@@ -1,64 +0,0 @@
-package server
-
-import (
-	"net/http"
-	"net/http/httptest"
-	"testing"
-)
-
-// TestCORSOnlyOnImageRoutes verifies that the image routes answer with the
-// configured access_control_allow_origin, a preflight request included, and
-// that the login and URL generator pages send no Access-Control-Allow-Origin,
-// so no other site can read them. /metrics is left out: its middleware
-// registers with the process-wide Prometheus registry, which only one test
-// in this package can do.
-func TestCORSOnlyOnImageRoutes(t *testing.T) {
-	t.Parallel()
-
-	const appOrigin = "https://app.example.com"
-
-	s := newTestServer(t)
-	s.config.AccessControlAllowOrigin = appOrigin
-	s.SetupRoutes()
-
-	requests := []struct {
-		method string
-		path   string
-		want   string
-	}{
-		{http.MethodGet, unsignedImagePath, appOrigin},
-		{http.MethodHead, unsignedImagePath, appOrigin},
-		{http.MethodOptions, unsignedImagePath, appOrigin},
-		{http.MethodGet, encryptedImagePath, appOrigin},
-		{http.MethodGet, "/", ""},
-		{http.MethodOptions, "/", ""},
-		{http.MethodPost, "/generate", ""},
-		{http.MethodGet, "/logout", ""},
-	}
-
-	for _, tc := range requests {
-		t.Run(tc.method+" "+tc.path, func(t *testing.T) {
-			t.Parallel()
-
-			req := httptest.NewRequestWithContext(
-				t.Context(), tc.method, tc.path, nil)
-			req.Header.Set("Origin", appOrigin)
-
-			// An OPTIONS request naming the method it asks about is the
-			// preflight a browser sends before some cross-origin requests.
-			if tc.method == http.MethodOptions {
-				req.Header.Set("Access-Control-Request-Method", http.MethodGet)
-			}
-
-			rec := httptest.NewRecorder()
-			s.ServeHTTP(rec, req)
-			t.Logf("status %d", rec.Code)
-
-			got := rec.Header().Get("Access-Control-Allow-Origin")
-			if got != tc.want {
-				t.Errorf("Access-Control-Allow-Origin = %q, want %q",
-					got, tc.want)
-			}
-		})
-	}
-}

internal/server/maintenance_internal_test.go

@@ -13,10 +13,6 @@ import (
 // unsignedImagePath is an image URL that carries no signature.
 const unsignedImagePath = "/v1/image/cdn.example.com/cat.jpg/100x100.jpeg"
 
-// encryptedImagePath is an encrypted image URL whose token cannot be
-// decrypted.
-const encryptedImagePath = "/v1/e/token/cat.jpg"
-
 // TestMaintenanceModeRefusesImageRequests verifies that while maintenance
 // mode is on, both image routes answer 503 Service Unavailable with a
 // Retry-After header and the JSON error body the image handlers send.
@@ -32,7 +28,7 @@ func TestMaintenanceModeRefusesImageRequests(t *testing.T) {
 	}{
 		{http.MethodGet, unsignedImagePath},
 		{http.MethodHead, unsignedImagePath},
-		{http.MethodGet, encryptedImagePath},
+		{http.MethodGet, "/v1/e/token/cat.jpg"},
 	}
 
 	for _, tc := range requests {
@@ -99,7 +95,7 @@ func TestImageRequestsServedWithoutMaintenanceMode(t *testing.T) {
 	}{
 		{http.MethodGet, unsignedImagePath, http.StatusUnauthorized},
 		{http.MethodHead, unsignedImagePath, http.StatusUnauthorized},
-		{http.MethodGet, encryptedImagePath, http.StatusBadRequest},
+		{http.MethodGet, "/v1/e/token/cat.jpg", http.StatusBadRequest},
 	}
 
 	for _, tc := range requests {

internal/server/routes.go

@@ -38,6 +38,7 @@ func (s *Server) SetupRoutes() {
 		s.router.Use(s.mw.Metrics())
 	}
 
+	s.router.Use(s.mw.CORS())
 	s.router.Use(middleware.Timeout(s.config.DownstreamTimeout))
 
 	if s.sentryEnabled {
@@ -73,31 +74,22 @@ func (s *Server) SetupRoutes() {
 
 	s.router.Get("/logout", s.h.HandleLogout())
 
-	// Image routes, the only ones that send CORS headers, as pages on other
-	// sites read them. They are a subrouter rather than a group: a group's
-	// middleware runs only for a request that matches one of its routes,
-	// and a browser's preflight OPTIONS request matches none, so the CORS
-	// middleware could not answer it.
-	s.router.Route("/v1", func(r chi.Router) {
-		r.Use(s.mw.CORS())
+	// Image routes, refused while maintenance mode is on. Only these: the
+	// image's Docker HEALTHCHECK requests the health check, a 503 there
+	// would make the container unhealthy, and upaas marks a deploy failed
+	// when its container is unhealthy.
+	s.router.Group(func(r chi.Router) {
+		r.Use(s.refuseDuringMaintenance)
 
-		// Refused while maintenance mode is on. Only these: the image's
-		// Docker HEALTHCHECK requests the health check, a 503 there would
-		// make the container unhealthy, and upaas marks a deploy failed
-		// when its container is unhealthy.
-		r.Group(func(r chi.Router) {
-			r.Use(s.refuseDuringMaintenance)
+		// Main image proxy route
+		// /v1/image/<host>/<path>/<width>x<height>.<format>
+		r.Get("/v1/image/*", s.h.HandleImage())
+		r.Head("/v1/image/*", s.h.HandleImage())
 
-			// Main image proxy route
-			// /v1/image/<host>/<path>/<width>x<height>.<format>
-			r.Get("/image/*", s.h.HandleImage())
-			r.Head("/image/*", s.h.HandleImage())
-
-			// Encrypted image URL route
-			// The trailing filename (e.g., /img.jpg) is ignored but helps
-			// browsers with content type
-			r.Get("/e/{token}/*", s.h.HandleImageEnc())
-		})
+		// Encrypted image URL route
+		// The trailing filename (e.g., /img.jpg) is ignored but helps
+		// browsers with content type
+		r.Get("/v1/e/{token}/*", s.h.HandleImageEnc())
 	})
 
 	// Metrics endpoint with auth