merge: PR #7 from feature/config

feature/config

Author: quyxishi

Makefile

@@ -3,11 +3,12 @@ all: build test
 # Build the application
 build:
 	@echo -- Building
-	@go build -o main.exe cmd/api/main.go
+	@go build -o whitebox.exe ./cmd/api
 
 # Run the application
 run:
-	@go run cmd/api/main.go
+	@echo -- Running
+	@go run ./cmd/api $(filter-out run,$(MAKECMDGOALS))
 
 # Test the application
 test:
@@ -17,7 +18,7 @@ test:
 # Clean the binary
 clean:
 	@echo -- Cleaning
-	@rm -f main
+	@rm -f whitebox
 
 # Live-Reload
 watch:
@@ -32,3 +33,6 @@ watch:
 	}"
 
 .PHONY: all build run test clean watch
+
+%:
+	@:

README.md

@@ -173,11 +173,11 @@ You can configure periodic probes using a simple `curl` command in a cron job or
 - [x] CI/CD for basic build/test workflow.
 - [x] JSON Subscriptions VPN-url's support.
 - [x] AmneziaWG protocol support.
-- [ ] Whitebox YAML configuration w/ auto-reload.
+- [x] Whitebox YAML configuration w/ auto-reload by SIGHUP.
+- [x] Response status/body validation.
+- [x] Custom HTTP-headers qualify support.
 - [ ] Authorization/OAuth 2.0 support.
 - [ ] Configuration for TLS protocol of HTTP probe support.
-- [ ] Response status/body validation.
-- [ ] Custom HTTP-headers qualify support.
 - [ ] More advanced metrics.
 
 ## Development

VERSION

@@ -1 +1 @@
-0.4.0
+1.0.0

cmd/api/cli.go

@@ -0,0 +1,41 @@
+package main
+
+import (
+	"log/slog"
+	"os"
+
+	"github.com/alecthomas/kong"
+	"github.com/goccy/go-yaml"
+	"github.com/quyxishi/whitebox/internal/config"
+)
+
+type CLI struct {
+	Version    kong.VersionFlag `short:"v" help:"Print version information and exit."`
+	ConfigPath string           `name:"config.file" short:"c" help:"Path to whitebox config file."`
+}
+
+func (h *CLI) LoadConfig() (*config.WhiteboxConfig, error) {
+	// if no config path provided, return default config
+	if h.ConfigPath == "" {
+		cfg := config.NewWhiteboxConfig()
+		return &cfg, nil
+	}
+
+	// if path provided, load from file
+	file, err := os.Open(h.ConfigPath)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		if err := file.Close(); err != nil {
+			slog.Error("failed to close file instance", "err", err)
+		}
+	}()
+
+	var config config.WhiteboxConfig
+	if err := yaml.NewDecoder(file).Decode(&config); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}

cmd/api/main.go

@@ -10,7 +10,10 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/alecthomas/kong"
+	"github.com/quyxishi/whitebox"
 	"github.com/quyxishi/whitebox/internal/api"
+	"github.com/quyxishi/whitebox/internal/config"
 	mlog "github.com/quyxishi/whitebox/internal/log"
 )
 
@@ -39,7 +42,48 @@ func gracefulShutdown(apiServer *http.Server, done chan bool) {
 	done <- true
 }
 
+func hotReloadLoop(cli *CLI, configWrapper *config.WhiteboxConfigWrapper) {
+	sigs := make(chan os.Signal, 1)
+	signal.Notify(sigs, syscall.SIGHUP)
+
+	for {
+		<-sigs // Listen for the sighup signal.
+		slog.Info("SIGHUP received, reloading config")
+
+		newConfig, err := cli.LoadConfig()
+		if err != nil {
+			slog.Error("Unable to reload config file", "err", err)
+			continue
+		}
+
+		configWrapper.Update(newConfig)
+		slog.Info("Config updated successfully")
+	}
+}
+
 func main() {
+	var cli CLI
+
+	parser := kong.Must(&cli,
+		kong.Name("whitebox"),
+		kong.Description("A Prometheus exporter that provides availability monitoring of external VPN services"),
+		kong.Vars{
+			"version": whitebox.Version(),
+		},
+	)
+
+	_, err := parser.Parse(os.Args[1:])
+	if err != nil {
+		parser.FatalIfErrorf(fmt.Errorf("unable to parse cli args due: %w", err))
+	}
+
+	cfg, err := cli.LoadConfig()
+	if err != nil {
+		parser.FatalIfErrorf(fmt.Errorf("unable to load config file due: %w", err))
+	}
+
+	wrapper := config.NewConfigWrapper(cfg)
+
 	// Initialize the default structured logger writing to stdout
 	// This configuration is flexible and can be adapted - e.g, by switching to JSON -
 	// to ensure compatibility with log ingestion and aggregation systems.
@@ -51,17 +95,24 @@ func main() {
 	handler := mlog.NewModuleHandler(os.Stdout, &opts)
 	slog.SetDefault(slog.New(handler))
 
+	if cli.ConfigPath == "" {
+		slog.Info("using default configuration (no config path provided)")
+	} else {
+		slog.Info("using configuration file w/", slog.Int("scopes", len(cfg.Scopes)), slog.String("path", cli.ConfigPath))
+	}
+
 	// *
 
-	server := api.NewServer()
+	server := api.NewServer(wrapper)
 
 	// Create a done channel to signal when the shutdown is complete.
 	done := make(chan bool, 1)
 
 	// Run graceful shutdown in a separate goroutine.
 	go gracefulShutdown(server, done)
+	go hotReloadLoop(&cli, wrapper)
 
-	err := server.ListenAndServe()
+	err = server.ListenAndServe()
 	if err != nil && err != http.ErrServerClosed {
 		panic(fmt.Sprintf("http server error: %s", err))
 	}

go.mod

@@ -3,32 +3,32 @@ module github.com/quyxishi/whitebox
 go 1.25.3
 
 require (
+	github.com/alecthomas/kong v1.13.0
 	github.com/gin-contrib/cors v1.7.6
 	github.com/gin-gonic/gin v1.11.0
+	github.com/goccy/go-yaml v1.19.1
 	github.com/joho/godotenv v1.5.1
 	gopkg.in/ini.v1 v1.67.0
 )
 
 require (
-	github.com/Masterminds/semver/v3 v3.4.0 // indirect
-	github.com/amnezia-vpn/amneziawg-go v0.2.11 // indirect
+	cel.dev/expr v0.24.0 // indirect
+	github.com/antlr4-go/antlr/v4 v4.13.0 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/emirpasic/gods/v2 v2.0.0-alpha // indirect
-	github.com/go-task/slim-sprig/v3 v3.0.0 // indirect
-	github.com/goccy/go-yaml v1.19.1 // indirect
-	github.com/google/pprof v0.0.0-20250403155104-27863c87afa6 // indirect
 	github.com/mattn/go-colorable v0.1.14 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
-	github.com/onsi/ginkgo/v2 v2.27.2 // indirect
 	github.com/prometheus/client_model v0.6.2 // indirect
 	github.com/prometheus/common v0.67.4 // indirect
 	github.com/prometheus/procfs v0.19.2 // indirect
 	github.com/quic-go/qpack v0.6.0 // indirect
 	github.com/rogpeppe/go-internal v1.14.1 // indirect
-	github.com/tevino/abool/v2 v2.1.0 // indirect
+	github.com/stoewer/go-strcase v1.2.0 // indirect
 	go.yaml.in/yaml/v2 v2.4.3 // indirect
+	golang.org/x/exp v0.0.0-20231110203233-9a3e6036ecaa // indirect
 	golang.zx2c4.com/wireguard v0.0.0-20250521234502-f333402bd9cb // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20251022142026-3a174f9686a8 // indirect
 )
 
 require (
@@ -42,17 +42,17 @@ require (
 	github.com/cloudflare/circl v1.6.1 // indirect
 	github.com/cloudwego/base64x v0.1.6 // indirect
 	github.com/dgryski/go-metro v0.0.0-20250106013310-edb8663e5e33 // indirect
-	github.com/emirpasic/gods v1.18.1 // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/gabriel-vasile/mimetype v1.4.12 // indirect
-	github.com/ghodss/yaml v1.0.1-0.20220118164431-d8423dcdf344 // indirect
+	github.com/ghodss/yaml v1.0.1-0.20220118164431-d8423dcdf344
 	github.com/gin-contrib/sse v1.1.0 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/go-playground/validator/v10 v10.30.0 // indirect
 	github.com/goccy/go-json v0.10.5 // indirect
 	github.com/gogf/gf/v2 v2.9.6
 	github.com/google/btree v1.1.3 // indirect
+	github.com/google/cel-go v0.26.1
 	github.com/gorilla/websocket v1.5.4-0.20250319132907-e064f32e3674 // indirect
 	github.com/gvcgo/vpnparser v0.2.7
 	github.com/json-iterator/go v1.1.12 // indirect
@@ -104,4 +104,4 @@ require (
 	lukechampine.com/blake3 v1.4.1 // indirect
 )
 
-replace gvisor.dev/gvisor => gvisor.dev/gvisor v0.0.0-20250828211149-1f30edfbb5d4
+replace gvisor.dev/gvisor => gvisor.dev/gvisor v0.0.0-20250828211149-1f30edfbb5d4