local-dev: Vite proxy for same-origin requests + upstream gateway Dockerfile fix

vite.config.ts now proxies `/api` and `/galaxy.gateway.v1.EdgeGateway`
to the gateway, so the browser sees only `localhost:5173` and never
trips a cross-origin preflight. `.env.development` accordingly points
`VITE_GATEWAY_BASE_URL` at the Vite origin. The proxy target is
overridable via `VITE_DEV_PROXY_TARGET=...` for non-default gateways
without touching the compose file.

`gateway/Dockerfile` previously failed to build because gateway
imports `galaxy/core` (replaced to `../ui/core` in `gateway/go.mod`)
but the Dockerfile did not copy `ui/core/` into the build context
nor declare the replace in the synthesised `go.work`. Adding both
makes `docker build -f gateway/Dockerfile .` succeed; this is the
same fix already shipped in `tools/local-dev/gateway.Dockerfile`,
back-ported to upstream.

Verified:
- docker build -f gateway/Dockerfile . — builds cleanly
- pnpm test 14/14, pnpm exec playwright test 44/44 (with CI=1 to
  force a fresh dev server; reuse keeps the previous startup env)
- curl POST through localhost:5173/api/* and /galaxy.gateway.v1.* —
  reach the gateway, no CORS preflight on the browser side

tools/local-dev/README.md updated with the new network map and the
`VITE_DEV_PROXY_TARGET` override.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

gateway/Dockerfile

@@ -1,9 +1,9 @@
 # syntax=docker/dockerfile:1.7
 
 # Build context is the workspace root (galaxy/), not the gateway/
-# subdirectory, because the gateway module pulls galaxy/{backend,model,
+# subdirectory, because the gateway module pulls
-# redisconn,transcoder} through the go.work replace directives. Build
+# galaxy/{backend,core,model,redisconn,transcoder} through the
-# with:
+# go.work replace directives. Build with:
 #
 #     docker build -t galaxy/gateway:integration -f gateway/Dockerfile .
 
@@ -23,6 +23,7 @@ COPY pkg/redisconn/  ./pkg/redisconn/
 COPY pkg/schema/     ./pkg/schema/
 COPY pkg/transcoder/ ./pkg/transcoder/
 COPY pkg/util/       ./pkg/util/
+COPY ui/core/        ./ui/core/
 COPY backend/        ./backend/
 COPY gateway/        ./gateway/
 
@@ -41,6 +42,7 @@ use (
 	./pkg/schema
 	./pkg/transcoder
 	./pkg/util
+	./ui/core
 )
 
 replace (
@@ -53,6 +55,7 @@ replace (
 	galaxy/schema v0.0.0     => ./pkg/schema
 	galaxy/transcoder v0.0.0 => ./pkg/transcoder
 	galaxy/util v0.0.0       => ./pkg/util
+	galaxy/core v0.0.0       => ./ui/core
 )
 EOF
 

tools/local-dev/README.md

@@ -73,22 +73,34 @@ the backend with the new env).
 
 ```
 host                                            compose network "galaxy-local-dev-net"
-  ┌────────────────────────────┐             ┌──────────────────────────────┐
+  ┌────────────────────────────────┐              ┌──────────────────────────────┐
-  │ pnpm dev   localhost:5173  │──HMR──▶│ host (Vite)                       │
+  │ browser    localhost:5173      │── pnpm dev (Vite, host) ──┐                  │
-  │ browser    localhost:8080  │──REST/Connect─▶│ gateway:8080            │
+  │           ↳ /api/*  proxied ───┼──────────────────────────▶│ gateway:8080     │
-  │ browser    localhost:8025  │─────▶│ mailpit:8025  (web UI)             │
+  │           ↳ /galaxy.gateway... ┼──────────────────────────▶│                  │
-  │ psql       localhost:5433  │─────▶│ postgres:5432                      │
+  │ browser    localhost:8025      │─────────────────────────▶│ mailpit:8025      │
-  │ redis-cli  localhost:6380  │─────▶│ redis:6379                         │
+  │ psql       localhost:5433      │─────────────────────────▶│ postgres:5432     │
-  └────────────────────────────┘             │  ↳ backend:8080  (HTTP)      │
+  │ redis-cli  localhost:6380      │─────────────────────────▶│ redis:6379        │
+  └────────────────────────────────┘              │  ↳ backend:8080  (HTTP)        │
                                                   │  ↳ backend:8081  (gRPC push)   │
                                                   │  ↳ mailpit:1025  (SMTP in)     │
-                                             └──────────────────────────────┘
+                                                  └────────────────────────────────┘
 ```
 
-Only the gateway public port (8080) and the mailpit web UI (8025)
+Vite's dev server proxies `/api` and `/galaxy.gateway.v1.EdgeGateway`
-are needed for normal UI work. Postgres (5433) and Redis (6380) are
+to the gateway, so every browser request stays same-origin (no CORS
-exposed for direct inspection (`make psql`, `redis-cli -h localhost
+preflight). The gateway is therefore reachable only through Vite at
--p 6380 -a galaxy-dev`).
+<http://localhost:5173>, not at <http://localhost:8080> from the
+browser tab. Direct curl/wget against <http://localhost:8080> still
+works for diagnostic probes — only the browser-side requests are
+proxied.
+
+Mailpit (8025), postgres (5433), and redis (6380) remain directly
+reachable for diagnostics (`make psql`, `redis-cli -h localhost -p
+6380 -a galaxy-dev`).
+
+To point the proxy at a non-local gateway, run
+`VITE_DEV_PROXY_TARGET=http://gateway.host:8080 pnpm -C ui/frontend dev`
+— no compose changes needed.
 
 ## Make targets
 

ui/frontend/.env.development

@@ -3,8 +3,14 @@
 # brought up by `make -C tools/local-dev up`. Per-developer overrides
 # live in `.env.development.local` (gitignored by Vite convention).
 
-# Gateway public REST + Connect-Web edge listener.
+# Gateway public REST + Connect-Web edge listener. Points at the Vite
-VITE_GATEWAY_BASE_URL=http://localhost:8080
+# dev server's own origin so the browser sees same-origin requests;
+# Vite then proxies `/api` and `/galaxy.gateway.v1.EdgeGateway` to the
+# real gateway at `http://localhost:8080`. See `vite.config.ts`. To
+# work against a non-local gateway, override the proxy target via
+# `VITE_DEV_PROXY_TARGET=http://gateway.host:8080 pnpm dev` (no UI
+# rebuild needed).
+VITE_GATEWAY_BASE_URL=http://localhost:5173
 
 # Standard non-URL-safe base64 of the gateway response-signing public
 # key. Pairs with `tools/local-dev/keys/gateway-response.pem`. The pair

ui/frontend/vite.config.ts

@@ -10,9 +10,36 @@ const pkg = JSON.parse(
 	),
 ) as { version: string };
 
+// Default upstream gateway address used by the dev proxy. Override by
+// pointing `VITE_DEV_PROXY_TARGET` at a different gateway when working
+// with a remote stack instead of `tools/local-dev/`.
+const DEV_PROXY_TARGET =
+	process.env.VITE_DEV_PROXY_TARGET ?? "http://localhost:8080";
+
 export default defineConfig({
 	plugins: [sveltekit()],
 	define: {
 		__APP_VERSION__: JSON.stringify(pkg.version),
 	},
+	server: {
+		// Same-origin proxy so the browser sees only `localhost:5173`
+		// and never trips a cross-origin preflight against the
+		// gateway's REST + Connect-Web surfaces. Production deployments
+		// serve the UI and the gateway behind a single host, so the
+		// proxy is purely a dev-time convenience.
+		proxy: {
+			"/api": {
+				target: DEV_PROXY_TARGET,
+				changeOrigin: false,
+			},
+			"/galaxy.gateway.v1.EdgeGateway": {
+				target: DEV_PROXY_TARGET,
+				changeOrigin: false,
+				// Connect-Web server-streaming (`SubscribeEvents`) uses
+				// chunked HTTP responses; http-proxy passes them through
+				// transparently as long as buffering stays off, which is
+				// the default.
+			},
+		},
+	},
 });