refactor: drop VITE_API_BASE_URL, always use relative /api

.github/workflows/ci.yml

@@ -111,7 +111,6 @@ jobs:
           file: backend/Dockerfile
           push: ${{ github.ref == 'refs/heads/main' || startsWith(github.ref, 'refs/tags/') }}
           build-args: |
-            VITE_API_BASE_URL=/api
             GIT_VERSION=${{ steps.git-version.outputs.value }}
           tags: ${{ steps.backend-meta.outputs.tags }}
           labels: ${{ steps.backend-meta.outputs.labels }}

README.md

@@ -10,26 +10,16 @@ Minimal portfolio app.
 
 ## Frontend backend URL
 
-The frontend reads the backend base URL from `VITE_API_BASE_URL`.
+The frontend always calls the backend under the relative `/api` path.
 
-1. Copy [`web/.env.example`](web/.env.example) to `web/.env.local`.
-2. Set `VITE_API_BASE_URL` to the backend URL you want the frontend to use.
-3. Start the frontend with `npm run dev` from `web/`.
-
-Example:
-
-```bash
-cp web/.env.example web/.env.local
-echo 'VITE_API_BASE_URL=http://127.0.0.1:3000/api' > web/.env.local
-```
-
-For local Vite development, set `VITE_API_BASE_URL` explicitly. If it is not set, the frontend defaults to `/api`, which is the path the backend exposes its API under when it serves the bundled frontend.
+- Production: the backend serves both the API and the bundled frontend, so same-origin `/api` requests just work.
+- Local development: the Vite dev server proxies `/api` to `http://127.0.0.1:3000` (see [`web/vite.config.ts`](web/vite.config.ts)), so no environment variable is needed. Start the backend with `cargo run` from `backend/`, then `npm run dev` from `web/`.
 
 ## Deployment
 
 The backend serves both the API and the bundled Vite frontend from a single container image:
 
-- [`backend/Dockerfile`](backend/Dockerfile) builds the Rust API and bundles the static frontend (built with `VITE_API_BASE_URL=/api`) into `/app/web`
+- [`backend/Dockerfile`](backend/Dockerfile) builds the Rust API and bundles the static frontend (which targets `/api`) into `/app/web`
 - [`docker-compose.yml`](docker-compose.yml) deploys the prebuilt tagged image
 - [`docker-compose.build.yml`](docker-compose.build.yml) adds local build support on top of the base compose file
 
@@ -69,7 +59,7 @@ export APP_TAG=dev
 docker compose -f docker-compose.yml -f docker-compose.build.yml up --build
 ```
 
-The base compose file keeps the final image name and tag stable. The build override adds `build:` and `pull_policy: never` so `--build` does not try to pull first. The build sets `VITE_API_BASE_URL=/api` by default.
+The base compose file keeps the final image name and tag stable. The build override adds `build:` and `pull_policy: never` so `--build` does not try to pull first.
 
 ### Runtime endpoints
 
@@ -81,7 +71,7 @@ The compose file uses a named volume for backend SQLite data.
 
 ### Frontend URL behavior
 
-The bundled frontend always targets `VITE_API_BASE_URL` as set at build time, defaulting to `/api`. For a deployment where the API is hosted on a separate public origin, rebuild the image with the desired public `VITE_API_BASE_URL`.
+The bundled frontend always targets the relative `/api` path on its own origin. To host the API on a separate public origin, place a reverse proxy that forwards `/api` to the backend.
 
 ### CI
 

backend/Dockerfile

@@ -6,8 +6,6 @@ WORKDIR /web
 COPY web/package.json web/package-lock.json ./
 RUN npm ci
 COPY web/ ./
-ARG VITE_API_BASE_URL=/api
-ENV VITE_API_BASE_URL=${VITE_API_BASE_URL}
 ARG GIT_VERSION
 ENV GIT_VERSION=${GIT_VERSION}
 RUN npm run build

docker-compose.build.yml

@@ -3,6 +3,4 @@ services:
     build:
       context: .
       dockerfile: backend/Dockerfile
-      args:
-        VITE_API_BASE_URL: ${VITE_API_BASE_URL:-/api}
     pull_policy: never

web/README.md

@@ -1,20 +1,8 @@
 # siniscalco web
 
-## Set the backend URL
+## Backend URL
 
-The frontend uses `VITE_API_BASE_URL` as the backend base URL.
+The frontend calls the backend under the relative `/api` path.
 
-For local Vite development, point it directly at the backend:
-
-1. Copy `.env.example` to `.env.local`.
-2. Set `VITE_API_BASE_URL`.
-3. Run `npm run dev`.
-
-Example:
-
-```bash
-cp .env.example .env.local
-echo 'VITE_API_BASE_URL=http://127.0.0.1:3000/api' > .env.local
-```
-
-If `VITE_API_BASE_URL` is not set, the app defaults to `/api`. That default is intended for the container build, where the backend serves the bundled frontend and exposes its API under `/api`.
+- Local development: the Vite dev server proxies `/api` to `http://127.0.0.1:3000` (see `vite.config.ts`). Start the backend with `cargo run` from `backend/`, then run `npm run dev`.
+- Production: the backend serves the bundled frontend and exposes its API under `/api`, so same-origin requests work out of the box.

web/src/lib/env.ts

@@ -1,5 +1,7 @@
+export const API_BASE_URL = "/api";
+
 export function getApiBaseUrl() {
-  return import.meta.env.VITE_API_BASE_URL?.trim() || "/api";
+  return API_BASE_URL;
 }
 
 export function getHealthApiUrl() {

web/vite.config.ts

@@ -22,6 +22,12 @@ function getGitVersion(): string {
 // https://vite.dev/config/
 export default defineConfig({
   plugins: [react(), tailwindcss()],
+  server: {
+    proxy: {
+      // Local development only: forward API calls to the backend started with `cargo run`.
+      "/api": "http://127.0.0.1:3000",
+    },
+  },
   define: {
     __APP_VERSION__: JSON.stringify(getGitVersion()),
   },