fix(web): refresh API proxy DNS after backend redeploy

Signed-off-by: XiaoSeS <87064762+XiaoSeS@users.noreply.github.com>

docker-compose.staging.yml

@@ -70,6 +70,7 @@ services:
       - ./web/dist:/usr/share/nginx/html:ro
       - ./web/nginx.conf.template:/etc/nginx/templates/default.conf.template:ro
     environment:
+      NGINX_ENTRYPOINT_LOCAL_RESOLVERS: "1"
       SKILLHUB_API_UPSTREAM: http://server:8080
       SKILLHUB_WEB_API_BASE_URL: ""
       SKILLHUB_PUBLIC_BASE_URL: ""

scripts/tests/nginx-forwarded-proto-test.sh

@@ -42,10 +42,12 @@ wait_for_nginx() {
 start_proxy() {
   local container="$1"
   local trust_forwarded_proto="$2"
+  local backend_name="${3:-$BACKEND}"
   docker run --detach \
     --name "$container" \
     --network "$NETWORK" \
-    --env "SKILLHUB_API_UPSTREAM=http://$BACKEND:8080" \
+    --env "NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1" \
+    --env "SKILLHUB_API_UPSTREAM=http://$backend_name:8080" \
     --env "SKILLHUB_TRUST_FORWARDED_PROTO=$trust_forwarded_proto" \
     --volume "$TEMPLATE:/etc/nginx/templates/default.conf.template:ro" \
     "$NGINX_IMAGE" >/dev/null
@@ -98,4 +100,80 @@ done
 assert_proto "$TRUSTED_PROXY" http
 assert_proto "$TRUSTED_PROXY" http "https,http"
 
-echo "nginx-forwarded-proto-test passed"
+DNS_BACKEND="${TEST_ID}-dns-backend"
+DNS_OLD_BACKEND="${TEST_ID}-dns-old"
+DNS_NEW_BACKEND="${TEST_ID}-dns-new"
+DNS_STALE_BACKEND="${TEST_ID}-dns-stale"
+DNS_PROXY="${TEST_ID}-dns-proxy"
+
+start_dns_backend() {
+  local container="$1"
+  local response="$2"
+  local alias="${3:-}"
+  local static_ip="${4:-}"
+  local config="$TMP_DIR/$container.conf"
+  cat >"$config" <<EOF
+server {
+    listen 8080;
+    location / {
+        default_type text/plain;
+        return 200 "$response";
+    }
+}
+EOF
+
+  local alias_args=()
+  local ip_args=()
+  if [[ -n "$alias" ]]; then
+    alias_args+=(--network-alias "$alias")
+  fi
+  if [[ -n "$static_ip" ]]; then
+    ip_args+=(--ip "$static_ip")
+  fi
+
+  docker run --detach \
+    --name "$container" \
+    --network "$NETWORK" \
+    "${alias_args[@]}" \
+    "${ip_args[@]}" \
+    --volume "$config:/etc/nginx/conf.d/default.conf:ro" \
+    "$NGINX_IMAGE" >/dev/null
+  CONTAINERS+=("$container")
+}
+
+container_ip() {
+  docker inspect --format "{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}" "$1"
+}
+
+start_dns_backend "$DNS_OLD_BACKEND" first "$DNS_BACKEND"
+start_proxy "$DNS_PROXY" false "$DNS_BACKEND"
+assert_dns_response() {
+  local expected="$1"
+  local actual
+  actual="$(docker exec "$DNS_PROXY" wget -qO- http://127.0.0.1/api/dns)" \
+    || fail "DNS proxy request failed; expected '$expected'"
+  [[ "$actual" == "$expected" ]] \
+    || fail "DNS proxy returned '$actual', expected '$expected'"
+}
+assert_dns_response first
+
+old_ip="$(container_ip "$DNS_OLD_BACKEND")"
+docker rm -f "$DNS_OLD_BACKEND" >/dev/null
+start_dns_backend "$DNS_STALE_BACKEND" stale "" "$old_ip"
+start_dns_backend "$DNS_NEW_BACKEND" second "$DNS_BACKEND"
+new_ip="$(container_ip "$DNS_NEW_BACKEND")"
+[[ "$old_ip" != "$new_ip" ]] || fail "replacement backend reused old IP $old_ip"
+
+refreshed=false
+for attempt in {1..36}; do
+  if actual="$(docker exec "$DNS_PROXY" wget -qO- http://127.0.0.1/api/dns 2>/dev/null)" \
+    && [[ "$actual" == second ]]; then
+    refreshed=true
+    break
+  fi
+  sleep 0.5
+done
+[[ "$refreshed" == true ]] \
+  || { docker logs "$DNS_PROXY" >&2 || true; fail "unchanged proxy did not reach replacement backend $new_ip"; }
+
+echo "nginx-forwarded-proto-test passed, including DNS refresh ($old_ip -> $new_ip)"

scripts/tests/web-base-path-nginx-smoke-test.sh

@@ -41,6 +41,7 @@ chmod +x "$entrypoint_d/20-base-path.sh" "$entrypoint_d/30-runtime-config.sh"
 
 if ! docker run -d --name "$name" \
     -p "$port:80" \
+    -e NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1 \
     -e SKILLHUB_API_UPSTREAM=http://127.0.0.1:9 \
     -e SKILLHUB_TRUST_FORWARDED_PROTO=false \
     -e SKILLHUB_WEB_BASE_PATH=/skillhub/ \
@@ -154,6 +155,7 @@ name_default="$name-default"
 port_default=18082
 docker run -d --name "$name_default" \
   -p "$port_default:80" \
+  -e NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1 \
   -e SKILLHUB_API_UPSTREAM=http://127.0.0.1:9 \
   -e SKILLHUB_TRUST_FORWARDED_PROTO=false \
   -e SKILLHUB_WEB_BASE_PATH=/skillhub/ \
@@ -206,6 +208,7 @@ name_trusted="$name-trusted"
 port_trusted=18083
 docker run -d --name "$name_trusted" \
   -p "$port_trusted:80" \
+  -e NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1 \
   -e SKILLHUB_API_UPSTREAM=http://127.0.0.1:9 \
   -e SKILLHUB_TRUST_FORWARDED_PROTO=true \
   -e SKILLHUB_WEB_BASE_PATH=/skillhub/ \
@@ -246,6 +249,7 @@ fixed_port=18081
 
 docker run -d --name "$fixed_name" \
   -p "$fixed_port:80" \
+  -e NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1 \
   -e SKILLHUB_API_UPSTREAM=http://127.0.0.1:9 \
   -e SKILLHUB_TRUST_FORWARDED_PROTO=false \
   -e SKILLHUB_WEB_BASE_PATH= \

web/Dockerfile

@@ -13,6 +13,7 @@ RUN pnpm build
 
 FROM nginx:alpine
 ENV SKILLHUB_TRUST_FORWARDED_PROTO=false
+ENV NGINX_ENTRYPOINT_LOCAL_RESOLVERS=1
 # Record a fixed build-time base so the entrypoint defaults SKILLHUB_WEB_BASE_PATH
 # to it and generates matching Nginx routing without repeating the value at runtime.
 # Placeholder builds (the default) intentionally write no file and default to '/'.

web/nginx.conf.template

@@ -2,6 +2,8 @@ server_tokens off;
 server {
     listen 80;
     server_name _;
+    resolver ${NGINX_LOCAL_RESOLVERS} valid=10s;
+    set $skillhub_api_upstream "${SKILLHUB_API_UPSTREAM}";
     root /usr/share/nginx/html;
     index index.html;
 
@@ -34,7 +36,7 @@ server {
     }
 
     location /api/ {
-        proxy_pass ${SKILLHUB_API_UPSTREAM};
+        proxy_pass $skillhub_api_upstream;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
@@ -43,7 +45,7 @@ server {
     }
 
     location /oauth2/ {
-        proxy_pass ${SKILLHUB_API_UPSTREAM};
+        proxy_pass $skillhub_api_upstream;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
@@ -52,7 +54,7 @@ server {
     }
 
     location /login/oauth2/ {
-        proxy_pass ${SKILLHUB_API_UPSTREAM};
+        proxy_pass $skillhub_api_upstream;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
@@ -61,7 +63,7 @@ server {
     }
 
     location /.well-known/ {
-        proxy_pass ${SKILLHUB_API_UPSTREAM};
+        proxy_pass $skillhub_api_upstream;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;