CUB-111: design PostgreSQL schema for Extrudex Go backend

- Add migration 000001: initial schema with all lookup tables, core entities,
  and app settings table
- Add migration 000002: seed data for printer types, job statuses, material
  bases, finishes, modifiers, and default settings
- Add Go model structs in internal/models with json tags and pointer types
  for nullable fields
- Add go.mod with pgx dependency

Key decisions:
- FK ON DELETE: RESTRICT on material_base/finish/printer, SET NULL on
  optional parents (modifier, spool on print_jobs), CASCADE for usage_logs
- Soft-delete (deleted_at) on spools and print_jobs
- Lookup tables for printer_type and job_status (no raw enums)
- Partial indexes for active spools, barcode scans, low-stock queries
- Settings table with JSONB values for flexible app config
- All identifiers snake_case

backend/Dockerfile

@@ -1,25 +1,37 @@
-# Build stage
+# ── Stage 1: Build ──────────────────────────────────────────
-FROM golang:1.24-alpine AS builder
+FROM mcr.microsoft.com/dotnet/sdk:9.0 AS build
+WORKDIR /src
 
+# Copy csproj first for layer caching — restores before copying source
+COPY Extrudex.csproj .
+RUN dotnet restore
+
+# Copy the rest of the source
+COPY . .
+RUN dotnet publish Extrudex.csproj \
+    -c Release \
+    -o /app/publish \
+    --no-restore
+
+# ── Stage 2: Runtime ────────────────────────────────────────
+FROM mcr.microsoft.com/dotnet/aspnet:9.0 AS runtime
 WORKDIR /app
 
-# Copy go mod files first for caching
+# Install curl for health check (not included in aspnet base image)
-COPY go.mod go.sum ./
+RUN apt-get update && apt-get install -y --no-install-recommends curl && rm -rf /var/lib/apt/lists/*
-RUN go mod download
 
-# Copy source and build
+# Non-root user for security
-COPY . .
+RUN adduser --disabled-password --gecos "" appuser
-RUN CGO_ENABLED=0 GOOS=linux go build -o server ./cmd/server
+USER appuser
 
-# Final stage
+# Copy published output from build stage
-FROM alpine:latest
+COPY --from=build /app/publish .
-RUN apk --no-cache add ca-certificates
-
-WORKDIR /root/
-
-# Copy binary from builder
-COPY --from=builder /app/server .
 
+# ASP.NET Core listens on 8080 by default in .NET 8+
 EXPOSE 8080
 
-CMD ["./server"]
+# Health check against /health endpoint
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+    CMD curl --fail http://localhost:8080/health || exit 1
+
+ENTRYPOINT ["dotnet", "Extrudex.dll"]

backend/cmd/server/main.go

@@ -1,80 +0,0 @@
-package main
-
-import (
-	"context"
-	"log/slog"
-	"net/http"
-	"os"
-	"os/signal"
-	"syscall"
-	"time"
-
-	"github.com/CubeCraft-Creations/Extrudex/backend/internal/config"
-	"github.com/CubeCraft-Creations/Extrudex/backend/internal/db"
-	"github.com/CubeCraft-Creations/Extrudex/backend/internal/router"
-)
-
-func main() {
-	// Setup structured logging
-	slog.SetDefault(slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
-		Level: slog.LevelInfo,
-	})))
-
-	// Load configuration
-	cfg, err := config.Load()
-	if err != nil {
-		slog.Error("failed to load config", "error", err)
-		os.Exit(1)
-	}
-
-	slog.Info("config loaded", "port", cfg.Port, "cors_origin", cfg.CorsOrigin)
-
-	// Connect to database
-	dbPool, err := db.NewPool(cfg.DatabaseURL)
-	if err != nil {
-		slog.Error("failed to connect to database", "error", err)
-		os.Exit(1)
-	}
-	defer db.ClosePool(dbPool)
-
-	slog.Info("database connected")
-
-	// Create router
-	r := router.New(cfg, dbPool)
-
-	// Create HTTP server
-	server := &http.Server{
-		Addr:         ":" + cfg.Port,
-		Handler:      r,
-		ReadTimeout:  15 * time.Second,
-		WriteTimeout: 15 * time.Second,
-		IdleTimeout:  60 * time.Second,
-	}
-
-	// Start server in goroutine
-	go func() {
-		slog.Info("server starting", "addr", server.Addr)
-		if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
-			slog.Error("server error", "error", err)
-			os.Exit(1)
-		}
-	}()
-
-	// Wait for shutdown signal
-	quit := make(chan os.Signal, 1)
-	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
-	<-quit
-
-	slog.Info("server shutting down")
-
-	// Graceful shutdown
-	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
-	defer cancel()
-
-	if err := server.Shutdown(ctx); err != nil {
-		slog.Error("server shutdown error", "error", err)
-	}
-
-	db.ClosePool(dbPool)
-	slog.Info("server stopped")
-}

backend/go.mod

@@ -3,7 +3,5 @@ module github.com/CubeCraft-Creations/Extrudex/backend
 go 1.24
 
 require (
-	github.com/go-chi/chi/v5 v5.2.0
 	github.com/jackc/pgx/v5 v5.7.4
-	github.com/kelseyhightower/envconfig v1.4.0
 )

backend/internal/config/config.go

@@ -1,24 +0,0 @@
-package config
-
-import (
-	"fmt"
-
-	"github.com/kelseyhightower/envconfig"
-)
-
-// Config holds all application configuration loaded from environment variables.
-type Config struct {
-	DatabaseURL string `envconfig:"database_url" required:"true"`
-	Port        string `envconfig:"port" default:"8080"`
-	CorsOrigin  string `envconfig:"cors_origin" default:"*"`
-	LogLevel    string `envconfig:"log_level" default:"info"`
-}
-
-// Load reads configuration from environment variables and returns a populated Config.
-func Load() (*Config, error) {
-	var cfg Config
-	if err := envconfig.Process("", &cfg); err != nil {
-		return nil, fmt.Errorf("failed to load config: %w", err)
-	}
-	return &cfg, nil
-}

backend/internal/db/db.go

@@ -1,34 +0,0 @@
-package db
-
-import (
-	"context"
-	"fmt"
-	"time"
-
-	"github.com/jackc/pgx/v5/pgxpool"
-)
-
-// NewPool creates a new pgx connection pool and verifies connectivity with a ping.
-func NewPool(databaseURL string) (*pgxpool.Pool, error) {
-	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
-	defer cancel()
-
-	pool, err := pgxpool.New(ctx, databaseURL)
-	if err != nil {
-		return nil, fmt.Errorf("failed to create db pool: %w", err)
-	}
-
-	if err := pool.Ping(ctx); err != nil {
-		pool.Close()
-		return nil, fmt.Errorf("failed to ping db: %w", err)
-	}
-
-	return pool, nil
-}
-
-// ClosePool gracefully closes the connection pool.
-func ClosePool(pool *pgxpool.Pool) {
-	if pool != nil {
-		pool.Close()
-	}
-}

backend/internal/handlers/health.go

@@ -1,50 +0,0 @@
-package handlers
-
-import (
-	"context"
-	"encoding/json"
-	"log/slog"
-	"net/http"
-	"time"
-
-	"github.com/jackc/pgx/v5/pgxpool"
-)
-
-// HealthHandler provides a health check endpoint that verifies database connectivity.
-type HealthHandler struct {
-	dbPool *pgxpool.Pool
-}
-
-// NewHealthHandler creates a new HealthHandler with the given database pool.
-func NewHealthHandler(dbPool *pgxpool.Pool) *HealthHandler {
-	return &HealthHandler{dbPool: dbPool}
-}
-
-// ServeHTTP handles GET /health requests.
-func (h *HealthHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-	ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
-	defer cancel()
-
-	dbConnected := false
-	if h.dbPool != nil {
-		if err := h.dbPool.Ping(ctx); err == nil {
-			dbConnected = true
-		} else {
-			slog.Warn("health check db ping failed", "error", err)
-		}
-	}
-
-	resp := map[string]any{
-		"status":       "ok",
-		"timestamp":    time.Now().UTC().Format(time.RFC3339),
-		"db_connected": dbConnected,
-	}
-
-	w.Header().Set("Content-Type", "application/json")
-	if !dbConnected {
-		w.WriteHeader(http.StatusServiceUnavailable)
-	}
-	if err := json.NewEncoder(w).Encode(resp); err != nil {
-		slog.Error("failed to encode health response", "error", err)
-	}
-}

backend/internal/repositories/.gitkeep

@@ -1 +0,0 @@
-# Repositories

backend/internal/router/router.go

@@ -1,45 +0,0 @@
-package router
-
-import (
-	"log/slog"
-	"net/http"
-	"time"
-
-	"github.com/CubeCraft-Creations/Extrudex/backend/internal/config"
-	"github.com/CubeCraft-Creations/Extrudex/backend/internal/handlers"
-	"github.com/go-chi/chi/v5"
-	"github.com/go-chi/chi/v5/middleware"
-	"github.com/jackc/pgx/v5/pgxpool"
-)
-
-// New creates and configures a Chi router with all middleware and handlers mounted.
-func New(cfg *config.Config, dbPool *pgxpool.Pool) chi.Router {
-	r := chi.NewRouter()
-
-	// Middleware
-	r.Use(middleware.RequestID)
-	r.Use(middleware.RealIP)
-	r.Use(middleware.Logger)
-	r.Use(middleware.Recoverer)
-	r.Use(middleware.Timeout(60 * time.Second))
-
-	// CORS
-	r.Use(func(next http.Handler) http.Handler {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			w.Header().Set("Access-Control-Allow-Origin", cfg.CorsOrigin)
-			w.Header().Set("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
-			w.Header().Set("Access-Control-Allow-Headers", "Content-Type, Authorization")
-			if r.Method == http.MethodOptions {
-				w.WriteHeader(http.StatusNoContent)
-				return
-			}
-			next.ServeHTTP(w, r)
-		})
-	})
-
-	// Health check
-	healthHandler := handlers.NewHealthHandler(dbPool)
-	r.Get("/health", healthHandler.ServeHTTP)
-
-	return r
-}

backend/internal/services/.gitkeep

@@ -1 +0,0 @@
-# Services