3 files changed, 35 insertions(+), 0 deletions(-)

M README.md
M chrome/chrome.go
M chrome/chrome_test.go

@@ 76,6 76,7 @@ copies of the same code.
 ```go
 svc := chrome.NewService(conf, "compare.sr.ht")
 svc.StyleHref = cssHref // after discovering the hashed stylesheet
+svc.Assets = map[string]string{"bundle.js": bundleHref} // any further artefacts
 
 t := chrome.MustAttach(template.New("layout").Funcs(chrome.Funcs()))
 // ... parse the service's own templates into t ...

@@ 135,6 135,20 @@ type Page struct {
 
 	StyleHref string // "" when the binary was built without a stylesheet
 
+	// Assets are the hashed hrefs of the extra build artefacts a layout links
+	// beyond the stylesheet — a vendored chart library, a front-end bundle —
+	// keyed by names the service picks. Read as {{index .Assets "uplot.js"}},
+	// guarded on emptiness exactly like StyleHref.
+	//
+	// They belong to the chrome for the reason StyleHref does: the hash in the
+	// name is a property of this binary, not of any page. A page that had to
+	// be handed its own asset URLs is a page that can be written without them
+	// and silently render nothing where the chart was.
+	//
+	// The map is the Service's, shared by every Page it builds: written once
+	// at startup, read-only afterwards. A handler must not write to it.
+	Assets map[string]string
+
 	Environment string // uppercased; banner text
 	ShowBanner  bool   // true outside production
 


@@ 175,6 189,9 @@ type Service struct {
 	// ExtraNav holds service-specific switcher entries (e.g. a /tokens link),
 	// rendered after the shared network entries, for authenticated viewers.
 	ExtraNav []NavItem
+	// Assets holds the extra hashed asset hrefs every Page carries; see
+	// Page.Assets. Populate it at startup, next to StyleHref.
+	Assets map[string]string
 
 	siteName    string
 	environment string


@@ 250,6 267,7 @@ func (s *Service) Page(r *http.Request, title, username string) Page {
 		SelfOrigin:     s.selfOrigin,
 		HubOrigin:      s.hubOrigin,
 		StyleHref:      s.StyleHref,
+		Assets:         s.Assets,
 		Environment:    strings.ToUpper(s.environment),
 		ShowBanner:     s.environment != "" && s.environment != "production",
 		ContainerClass: "container",

@@ 201,6 201,22 @@ func TestLoginURLForMatchesTheNav(t *testing.T) {
 		"https%3A%2F%2Fcompare.example%2F~alice%2Fdemo%3Fa%3D1", svc.LoginURLFor(r))
 }
 
+// TestPageCarriesTheServiceAssets pins the slot three services grew their own
+// copy of: the layout reads an extra hashed artefact off the chrome, not off
+// the page's payload.
+func TestPageCarriesTheServiceAssets(t *testing.T) {
+	svc := NewService(testConf(), "bench.sr.ht")
+	svc.Assets = map[string]string{"uplot.js": "/static/uplot.0badc0de.js"}
+	p := svc.Page(httptest.NewRequest("GET", "/", nil), "t", "alice")
+
+	assert.Equal(t, "/static/uplot.0badc0de.js", p.Assets["uplot.js"])
+	// A name the service never registered reads as empty, which is what the
+	// layout's {{if}} guard is written against.
+	assert.Empty(t, p.Assets["missing.js"])
+	assert.Empty(t, NewService(testConf(), "bench.sr.ht").
+		Page(httptest.NewRequest("GET", "/", nil), "t", "alice").Assets)
+}
+
 func TestServiceAccessors(t *testing.T) {
 	svc := NewService(testConf(), "compare.sr.ht")
 	assert.Equal(t, "https://compare.example", svc.SelfOrigin())