feat: initialize nuntius project with full server implementation

2026-06-20 20:48:09 +02:00
commit 1b700f7975
33 changed files with 4313 additions and 0 deletions
@@ -0,0 +1,231 @@
+//go:build linux || freebsd
+
+// Package config loads nuntius configuration from a TOML file.
+//
+// Configuration supports env var expansion for secrets:
+//  1. A TOML file (config.toml) — checked into the repo or provisioned
+//     per environment. Holds non-secret defaults and references to env vars.
+//  2. Environment variables — used for secrets like SMTP passwords.
+//     Reference them in the TOML file as ${VAR_NAME} or $VAR_NAME.
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"codeberg.org/petrbalvin/interpres"
+)
+
+// ValidFormTypes lists the form types nuntius knows how to handle.
+// Each form's `type` field is validated against this list in validate().
+var ValidFormTypes = map[string]bool{
+	"contact":    true,
+	"feedback":   true,
+	"newsletter": true,
+	"generic":    true,
+}
+
+// Config is the root configuration for nuntius.
+type Config struct {
+	Server  ServerConfig `toml:"server"`
+	Forms   []Form       `toml:"forms"`
+	DataDir string       `toml:"data_dir"`
+}
+
+// ServerConfig holds server-wide settings.
+type ServerConfig struct {
+	Port int `toml:"port"`
+}
+
+// Form is one contact / feedback / newsletter endpoint.
+type Form struct {
+	Name             string     `toml:"name"`
+	Path             string     `toml:"path"`
+	Type             string     `toml:"type"`
+	SMTP             SMTPConfig `toml:"smtp"`
+	To               string     `toml:"to"`
+	From             string     `toml:"from"`
+	RateLimitPerHour int        `toml:"rate_limit_per_hour"`
+	HoneypotField    string     `toml:"honeypot_field"`
+	AllowedOrigins   []string   `toml:"allowed_origins"`
+}
+
+// SMTPConfig holds SMTP credentials and connection details.
+type SMTPConfig struct {
+	Host     string `toml:"host"`
+	Port     int    `toml:"port"`
+	User     string `toml:"user"`
+	Password string `toml:"password"`
+}
+
+// Load reads, expands env vars in, and parses the TOML file at path.
+// If the file does not exist, a default template is created first.
+func Load(path string) (*Config, error) {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+			return nil, fmt.Errorf("mkdir %s: %w", filepath.Dir(path), err)
+		}
+		if err := os.WriteFile(path, defaultConfig, 0644); err != nil {
+			return nil, fmt.Errorf("write default config to %s: %w", path, err)
+		}
+	}
+	raw, err := os.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("read %s: %w", path, err)
+	}
+
+	// Step 1: expand ${VAR_NAME} references in the raw text.
+	expanded := os.Expand(string(raw), os.Getenv)
+
+	// Step 2: parse TOML, rejecting unknown fields to catch typos early.
+	var cfg Config
+	if err := interpres.NewDecoder().DisallowUnknownFields().Decode([]byte(expanded), &cfg); err != nil {
+		return nil, fmt.Errorf("parse %s: %w", path, err)
+	}
+
+	if err := cfg.validate(); err != nil {
+		return nil, err
+	}
+
+	return &cfg, nil
+}
+
+// validate runs sanity checks on the loaded config and applies defaults.
+func (c *Config) validate() error {
+	if c.Server.Port == 0 {
+		c.Server.Port = 8080
+	}
+	if c.DataDir == "" {
+		c.DataDir = "./data"
+	}
+	if len(c.Forms) == 0 {
+		return fmt.Errorf("at least one form must be defined under `forms`")
+	}
+
+	paths := make(map[string]string, len(c.Forms))
+	for i := range c.Forms {
+		f := &c.Forms[i]
+		if f.Name == "" {
+			return fmt.Errorf("form #%d: name is required", i+1)
+		}
+		if f.Path == "" {
+			return fmt.Errorf("form %q: path is required", f.Name)
+		}
+		if f.Type == "" {
+			c.Forms[i].Type = "contact"
+		}
+		if !ValidFormTypes[c.Forms[i].Type] {
+			supported := make([]string, 0, len(ValidFormTypes))
+			for k := range ValidFormTypes {
+				supported = append(supported, k)
+			}
+			return fmt.Errorf("form %q: type %q is not supported (must be one of: %s)",
+				f.Name, c.Forms[i].Type, strings.Join(supported, ", "))
+		}
+		if !strings.HasPrefix(f.Path, "/") {
+			return fmt.Errorf("form %q: path must start with /", f.Name)
+		}
+		if existing, ok := paths[f.Path]; ok {
+			return fmt.Errorf("form %q: duplicate path %q (also used by %q)", f.Name, f.Path, existing)
+		}
+		paths[f.Path] = f.Name
+
+		if f.SMTP.Host == "" {
+			return fmt.Errorf("form %q: smtp.host is required", f.Name)
+		}
+		if f.SMTP.Port == 0 {
+			return fmt.Errorf("form %q: smtp.port is required", f.Name)
+		}
+		if f.SMTP.User == "" {
+			return fmt.Errorf("form %q: smtp.user is required", f.Name)
+		}
+		if f.To == "" {
+			return fmt.Errorf("form %q: `to` is required", f.Name)
+		}
+		if f.From == "" {
+			// Default From to the SMTP user.
+			c.Forms[i].From = f.SMTP.User
+		}
+		if f.RateLimitPerHour == 0 {
+			c.Forms[i].RateLimitPerHour = 10
+		}
+		if f.HoneypotField == "" {
+			c.Forms[i].HoneypotField = "website"
+		}
+	}
+
+	return nil
+}
+
+// ConfigPath returns the canonical path for nuntius configuration.
+func ConfigPath() string {
+	return "/etc/nuntius/config.toml"
+}
+
+// AddrFor returns "host:port" for the given SMTP config.
+func (s SMTPConfig) AddrFor() string {
+	return s.Host + ":" + strconv.Itoa(s.Port)
+}
+
+// defaultConfig is written to disk when no config exists yet.
+var defaultConfig = []byte(`# nuntius configuration.
+#
+# Secrets (SMTP passwords) are referenced as ${VAR_NAME} and expanded from the
+# environment at startup, so they never live in this file.
+
+data_dir = "./data"
+
+[server]
+port = 8080
+
+[[forms]]
+name = "contact"
+type = "contact"
+path = "/api/nuntius/contact"
+to = "you@example.com"
+from = "contact@example.com"
+rate_limit_per_hour = 10
+honeypot_field = "website"
+allowed_origins = ["https://example.com"]
+
+  [forms.smtp]
+  host = "smtp.example.com"
+  port = 587
+  user = "contact@example.com"
+  password = "${NUNTIUS_SMTP_PASSWORD}"
+
+[[forms]]
+name = "feedback"
+type = "feedback"
+path = "/api/nuntius/feedback"
+to = "you@example.com"
+from = "contact@example.com"
+rate_limit_per_hour = 10
+honeypot_field = "website"
+allowed_origins = ["https://example.com"]
+
+  [forms.smtp]
+  host = "smtp.example.com"
+  port = 587
+  user = "contact@example.com"
+  password = "${NUNTIUS_SMTP_PASSWORD}"
+
+[[forms]]
+name = "newsletter"
+type = "newsletter"
+path = "/api/nuntius/newsletter"
+to = "you@example.com"
+from = "contact@example.com"
+rate_limit_per_hour = 100
+honeypot_field = "bot_email"
+allowed_origins = ["https://example.com"]
+
+  [forms.smtp]
+  host = "smtp.example.com"
+  port = 587
+  user = "contact@example.com"
+  password = "${NUNTIUS_SMTP_PASSWORD}"
+`)
@@ -0,0 +1,94 @@
+//go:build linux || freebsd
+
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestLoadWritesAndParsesDefault(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.toml")
+
+	// The first Load writes the default template, then parses it back.
+	cfg, err := Load(path)
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.Server.Port != 8080 {
+		t.Errorf("Server.Port = %d, want 8080", cfg.Server.Port)
+	}
+	if cfg.DataDir != "./data" {
+		t.Errorf("DataDir = %q, want ./data", cfg.DataDir)
+	}
+	if len(cfg.Forms) != 3 {
+		t.Fatalf("len(Forms) = %d, want 3", len(cfg.Forms))
+	}
+	if cfg.Forms[0].Name != "contact" || cfg.Forms[0].SMTP.Host != "smtp.example.com" {
+		t.Errorf("Forms[0] = %#v", cfg.Forms[0])
+	}
+	if cfg.Forms[2].RateLimitPerHour != 100 {
+		t.Errorf("newsletter rate_limit_per_hour = %d, want 100", cfg.Forms[2].RateLimitPerHour)
+	}
+}
+
+func TestLoadExpandsEnvVars(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.toml")
+	doc := `
+data_dir = "./data"
+
+[server]
+port = 9000
+
+[[forms]]
+name = "contact"
+type = "contact"
+path = "/api/nuntius/contact"
+to = "you@example.com"
+
+  [forms.smtp]
+  host = "smtp.example.com"
+  port = 587
+  user = "u@example.com"
+  password = "${NUNTIUS_TEST_PW}"
+`
+	if err := os.WriteFile(path, []byte(doc), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	t.Setenv("NUNTIUS_TEST_PW", "s3cret")
+
+	cfg, err := Load(path)
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	if cfg.Forms[0].SMTP.Password != "s3cret" {
+		t.Errorf("password = %q, want s3cret", cfg.Forms[0].SMTP.Password)
+	}
+}
+
+func TestLoadRejectsUnknownField(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.toml")
+	doc := `
+bogus = true
+
+[server]
+port = 8080
+
+[[forms]]
+name = "contact"
+path = "/api/nuntius/contact"
+to = "you@example.com"
+
+  [forms.smtp]
+  host = "smtp.example.com"
+  port = 587
+  user = "u@example.com"
+`
+	if err := os.WriteFile(path, []byte(doc), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := Load(path); err == nil {
+		t.Fatal("expected an error for an unknown field")
+	}
+}