From c895a67c4b6c6c3f9186b6157ad60afca5b908e5 Mon Sep 17 00:00:00 2001
From: sysops <sysops@LenovoT14Gen5>
Date: Thu, 27 Aug 2026 17:27:59 +0200
Subject: [PATCH] core: initial Go module skeleton (config, db pool, tenant
 registry migration)

---
 .gitignore                          |  2 ++
 DEVLOG.md                           | 46 +++++++++++++++++++++++++++++
 cmd/core/main.go                    | 33 +++++++++++++++++++++
 go.mod                              |  5 ++++
 internal/config/config.go           | 29 ++++++++++++++++++
 internal/db/db.go                   | 11 +++++++
 migrations/0001_tenant_registry.sql | 10 +++++++
 7 files changed, 136 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 DEVLOG.md
 create mode 100644 cmd/core/main.go
 create mode 100644 go.mod
 create mode 100644 internal/config/config.go
 create mode 100644 internal/db/db.go
 create mode 100644 migrations/0001_tenant_registry.sql

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ac00d6f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+*.log
+.env
diff --git a/DEVLOG.md b/DEVLOG.md
new file mode 100644
index 0000000..7178fe5
--- /dev/null
+++ b/DEVLOG.md
@@ -0,0 +1,46 @@
+# code – Dev Log
+
+## 2026-08-27 17:17 – 17:18 (0m)
+**Beschreibung:** Claude Code Session
+**Projekt:** nexarch
+
+### Commits
+Keine Commits in dieser Session.
+
+### Geänderte Dateien
+Keine Änderungen ermittelbar.
+
+---
+## 2026-08-27 17:21 – 17:21 (0m)
+**Beschreibung:** Claude Code Session
+**Projekt:** code
+
+### Commits
+Keine Commits in dieser Session.
+
+### Geänderte Dateien
+Keine Änderungen ermittelbar.
+
+---
+## 2026-08-27 17:22 – 17:22 (0m)
+**Beschreibung:** Claude Code Session
+**Projekt:** code
+
+### Commits
+Keine Commits in dieser Session.
+
+### Geänderte Dateien
+Keine Änderungen ermittelbar.
+
+---
+## 2026-08-27 17:23 – 17:25 (2m)
+**Beschreibung:** Claude Code Session
+**Projekt:** code
+
+### Commits
+Keine Commits in dieser Session.
+
+### Geänderte Dateien
+Keine Änderungen ermittelbar.
+
+---
diff --git a/cmd/core/main.go b/cmd/core/main.go
new file mode 100644
index 0000000..f8e362e
--- /dev/null
+++ b/cmd/core/main.go
@@ -0,0 +1,33 @@
+package main
+
+import (
+	"context"
+	"log"
+	"net/http"
+
+	"gitea.perlbach24.de/scripte/nexarch/internal/config"
+	"gitea.perlbach24.de/scripte/nexarch/internal/db"
+)
+
+func main() {
+	cfg, err := config.Load()
+	if err != nil {
+		log.Fatalf("config: %v", err)
+	}
+
+	pool, err := db.Connect(context.Background(), cfg.RegistryDSN)
+	if err != nil {
+		log.Fatalf("db: %v", err)
+	}
+	defer pool.Close()
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	})
+
+	log.Printf("nexarch-core listening on %s", cfg.ListenAddr)
+	if err := http.ListenAndServe(cfg.ListenAddr, mux); err != nil {
+		log.Fatalf("server: %v", err)
+	}
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..75a79b7
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module gitea.perlbach24.de/scripte/nexarch
+
+go 1.22
+
+require github.com/jackc/pgx/v5 v5.6.0
diff --git a/internal/config/config.go b/internal/config/config.go
new file mode 100644
index 0000000..d51dc5f
--- /dev/null
+++ b/internal/config/config.go
@@ -0,0 +1,29 @@
+package config
+
+import (
+	"fmt"
+	"os"
+)
+
+// Config holds startup configuration for the core module.
+// RegistryDSN points at the control-plane registry DB (tenant list,
+// connection info, superadmin accounts) — see nexarch-state.json
+// multi_tenancy: Modell C (physisch getrennte DB pro Mandant).
+type Config struct {
+	ListenAddr  string
+	RegistryDSN string
+}
+
+func Load() (Config, error) {
+	dsn := os.Getenv("NEXARCH_REGISTRY_DSN")
+	if dsn == "" {
+		return Config{}, fmt.Errorf("NEXARCH_REGISTRY_DSN not set")
+	}
+
+	addr := os.Getenv("NEXARCH_LISTEN_ADDR")
+	if addr == "" {
+		addr = ":8080"
+	}
+
+	return Config{ListenAddr: addr, RegistryDSN: dsn}, nil
+}
diff --git a/internal/db/db.go b/internal/db/db.go
new file mode 100644
index 0000000..4a97193
--- /dev/null
+++ b/internal/db/db.go
@@ -0,0 +1,11 @@
+package db
+
+import (
+	"context"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+func Connect(ctx context.Context, dsn string) (*pgxpool.Pool, error) {
+	return pgxpool.New(ctx, dsn)
+}
diff --git a/migrations/0001_tenant_registry.sql b/migrations/0001_tenant_registry.sql
new file mode 100644
index 0000000..3b01739
--- /dev/null
+++ b/migrations/0001_tenant_registry.sql
@@ -0,0 +1,10 @@
+-- Control-plane registry: tenant list + connection info (Modell C).
+-- Core TEN-01 (siehe core-kanban).
+CREATE TABLE tenants (
+    id           UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    slug         TEXT NOT NULL UNIQUE,
+    name         TEXT NOT NULL,
+    db_dsn       TEXT NOT NULL,
+    status       TEXT NOT NULL DEFAULT 'active',
+    created_at   TIMESTAMPTZ NOT NULL DEFAULT now()
+);