Give Hammerhead its own edge with a built-in dashboard route; setup.sh installs it with Blacktip instead of Caddy

HAMMERHEAD_SELF_DOMAIN creates an edge for this machine, writes its token to <data>/self-edge.env
and adds an https route for the dashboard to that edge's config, so no reverse proxy is needed.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

selfedge_test.go

@@ -0,0 +1,98 @@
+package hammerhead
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"git.veillax.com/Veillax/hammerhead/internal/secretbox"
+	"git.veillax.com/Veillax/reef/model"
+)
+
+func edgeConfigOf(t *testing.T, s *Server, token string) model.EdgeConfig {
+	t.Helper()
+	ts := httptest.NewServer(s.Handler())
+	defer ts.Close()
+	req, _ := http.NewRequest("GET", ts.URL+"/edge/config?v=0", nil)
+	req.Header.Set("Authorization", "Bearer "+token)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	var cfg model.EdgeConfig
+	if resp.StatusCode != 200 {
+		t.Fatalf("edge config: %s", resp.Status)
+	}
+	json.NewDecoder(resp.Body).Decode(&cfg)
+	return cfg
+}
+
+func tokenFile(t *testing.T, dir string) string {
+	b, err := os.ReadFile(filepath.Join(dir, "self-edge.env"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	return strings.TrimSpace(strings.SplitN(strings.SplitN(string(b), "BLACKTIP_TOKEN=", 2)[1], "\n", 2)[0])
+}
+
+var key = secretbox.GenerateKey()
+
+func TestSelfEdgeServesTheDashboardWithoutAProxy(t *testing.T) {
+	dir := t.TempDir()
+	opts := Options{MasterKey: key, SelfDomain: "Hammerhead.Example.com", SelfTarget: "127.0.0.1:8080"}
+	s, err := New(dir, opts)
+	if err != nil {
+		t.Fatal(err)
+	}
+	token := tokenFile(t, dir)
+	cfg := edgeConfigOf(t, s, token)
+	if len(cfg.Mappings) != 1 || len(cfg.Local) != 1 {
+		t.Fatalf("mappings=%d local=%d", len(cfg.Mappings), len(cfg.Local))
+	}
+	m := cfg.Mappings[0]
+	if m.Proto != model.ProtoHTTPS || m.Hostname != "hammerhead.example.com" || m.Port != 443 || !m.RedirectHTTP || !m.Enabled ||
+		len(m.Targets) != 1 || m.Targets[0].Host != "127.0.0.1" || m.Targets[0].Port != 8080 || m.Targets[0].SiteID != cfg.Local[0] {
+		t.Fatalf("unexpected dashboard route: %+v", m)
+	}
+	if m.Auth.Protected() {
+		t.Fatal("the dashboard has its own login and must not sit behind resource auth")
+	}
+	edgeID := s.st.Settings.SelfEdgeID
+	if info, _ := os.Stat(filepath.Join(dir, "self-edge.env")); info.Mode().Perm()&0o077 != 0 && os.PathSeparator == '/' {
+		t.Fatalf("token file is readable by others: %v", info.Mode())
+	}
+	s.Close()
+
+	// a restart keeps the same edge and token instead of making a new one
+	s2, err := New(dir, opts)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer s2.Close()
+	if s2.st.Settings.SelfEdgeID != edgeID || tokenFile(t, dir) != token || len(s2.st.Edges) != 1 {
+		t.Fatal("restart changed the self edge")
+	}
+	if len(edgeConfigOf(t, s2, token).Mappings) != 1 {
+		t.Fatal("route missing after restart")
+	}
+}
+
+func TestNoSelfEdgeUnlessAsked(t *testing.T) {
+	dir := t.TempDir()
+	s, err := New(dir, Options{MasterKey: key})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer s.Close()
+	if len(s.st.Edges) != 0 {
+		t.Fatal("an edge appeared without HAMMERHEAD_SELF_DOMAIN")
+	}
+	if _, err := os.Stat(filepath.Join(dir, "self-edge.env")); err == nil {
+		t.Fatal("token file written without HAMMERHEAD_SELF_DOMAIN")
+	}
+}