test(env): add MCP_PORT port binding test

Author: francescobianco

tests/env/test-mcp-port.sh

@@ -0,0 +1,131 @@
+#!/usr/bin/env bash
+# =============================================================================
+# tests/env/test-mcp-port.sh
+# =============================================================================
+# Verifies that the MCP_PORT environment variable actually changes the port
+# the server binds to. Starts the server twice:
+#   1. default (no MCP_PORT) → expects port 8080
+#   2. custom  (MCP_PORT=19876) → expects port 19876, NOT 8080
+#
+# Does NOT require an OPENAPI_TOKEN — only checks TCP connectivity.
+#
+# Usage:
+#   bash tests/env/test-mcp-port.sh
+#
+# Exit code: 0 if all tests pass, 1 if any fail.
+# =============================================================================
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+ROOT_DIR="$(cd "$SCRIPT_DIR/../.." && pwd)"
+SRC_DIR="$ROOT_DIR/src"
+
+CUSTOM_PORT=19876
+DEFAULT_PORT=8080
+WAIT_TIMEOUT=20
+
+PASS=0
+FAIL=0
+SERVER_PID=""
+
+# --- Colors ---
+GREEN='\033[0;32m'; RED='\033[0;31m'; YELLOW='\033[1;33m'; CYAN='\033[0;36m'; NC='\033[0m'
+
+pass()    { printf "${GREEN}[PASS]${NC} %s\n" "$1"; PASS=$((PASS+1)); }
+fail()    { printf "${RED}[FAIL]${NC} %s\n"   "$1"; FAIL=$((FAIL+1)); }
+info()    { printf "${YELLOW}[INFO]${NC} %s\n" "$1"; }
+section() { printf "\n${CYAN}=== %s ===${NC}\n" "$1"; }
+
+kill_server() {
+    if [ -n "$SERVER_PID" ] && kill -0 "$SERVER_PID" 2>/dev/null; then
+        kill "$SERVER_PID" 2>/dev/null || true
+        wait "$SERVER_PID" 2>/dev/null || true
+        SERVER_PID=""
+    fi
+}
+
+cleanup() {
+    kill_server
+}
+trap cleanup EXIT
+
+# Wait up to $WAIT_TIMEOUT seconds for a TCP port to be reachable.
+wait_for_port() {
+    local port="$1"
+    for i in $(seq 1 "$WAIT_TIMEOUT"); do
+        if curl -s --max-time 1 -o /dev/null "http://localhost:${port}/" 2>/dev/null; then
+            info "Port ${port} ready after ${i}s"
+            return 0
+        fi
+        sleep 1
+    done
+    return 1
+}
+
+# Check that a port is NOT listening (give it a moment to confirm absence).
+port_is_closed() {
+    local port="$1"
+    ! curl -s --max-time 1 -o /dev/null "http://localhost:${port}/" 2>/dev/null
+}
+
+start_server() {
+    local port="$1"
+    MCP_PORT="$port" PYTHONPATH="$SRC_DIR" \
+        python3 -m openapi_mcp_sdk.main \
+        > /dev/null 2>&1 &
+    SERVER_PID=$!
+}
+
+# =============================================================================
+# STEP 1 — Custom port (MCP_PORT=19876)
+# =============================================================================
+section "MCP_PORT=${CUSTOM_PORT} — server binds on custom port"
+
+info "Starting server with MCP_PORT=${CUSTOM_PORT}..."
+start_server "$CUSTOM_PORT"
+
+if wait_for_port "$CUSTOM_PORT"; then
+    pass "Server is reachable on port ${CUSTOM_PORT}"
+else
+    fail "Server did not come up on port ${CUSTOM_PORT} within ${WAIT_TIMEOUT}s"
+fi
+
+if port_is_closed "$DEFAULT_PORT"; then
+    pass "Port ${DEFAULT_PORT} (default) is NOT open — custom port was used"
+else
+    fail "Port ${DEFAULT_PORT} (default) is also open — MCP_PORT was ignored"
+fi
+
+kill_server
+
+# Give the OS a moment to release the ports before the next step.
+sleep 2
+
+# =============================================================================
+# STEP 2 — Default port (no MCP_PORT set)
+# =============================================================================
+section "No MCP_PORT — server binds on default port ${DEFAULT_PORT}"
+
+info "Starting server without MCP_PORT..."
+start_server "$DEFAULT_PORT"
+
+if wait_for_port "$DEFAULT_PORT"; then
+    pass "Server is reachable on default port ${DEFAULT_PORT}"
+else
+    fail "Server did not come up on default port ${DEFAULT_PORT} within ${WAIT_TIMEOUT}s"
+fi
+
+if port_is_closed "$CUSTOM_PORT"; then
+    pass "Port ${CUSTOM_PORT} (custom) is NOT open — default port was used"
+else
+    fail "Port ${CUSTOM_PORT} (custom) is also open — unexpected"
+fi
+
+kill_server
+
+# =============================================================================
+# Summary
+# =============================================================================
+printf "\n"
+printf "Results: ${GREEN}%d passed${NC}, ${RED}%d failed${NC}\n" "$PASS" "$FAIL"
+[ "$FAIL" -eq 0 ]