✨ Add HTTP server scaffolding

cmd/main.go

@@ -2,15 +2,112 @@
 package main
 
 import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"os/signal"
+	"path"
+	"strings"
+	"sync"
+	"syscall"
+
+	"github.com/LiskHQ/op-fault-detector/pkg/api"
+	"github.com/LiskHQ/op-fault-detector/pkg/config"
 	"github.com/LiskHQ/op-fault-detector/pkg/log"
+	"github.com/spf13/viper"
 )
 
+var apiServer *api.HTTPServerWrapper
+
 func main() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
 	logger, err := log.NewDefaultProductionLogger()
 	if err != nil {
 		panic(err)
 	}
 
-	// To be removed after implementation
-	logger.Info("Running fault detector")
+	configFilepath := flag.String("config", "./config.yaml", "Path to the config file")
+	flag.Parse()
+	config, err := getAppConfig(logger, *configFilepath)
+	if err != nil {
+		panic(err)
+	}
+
+	wg := sync.WaitGroup{}
+
+	doneChan := make(chan struct{})
+	signalChan := make(chan os.Signal, 1)
+	signal.Notify(signalChan, os.Interrupt, syscall.SIGTERM)
+
+	// Start Fault Detector
+
+	// Start API Server
+	serverChan := make(chan error, 1)
+	apiServer = api.NewHTTPServer(ctx, logger, &wg, config, serverChan)
+	wg.Add(1)
+	go apiServer.Start()
+
+	go func() {
+		wg.Wait()
+		close(doneChan)
+	}()
+
+	for {
+		select {
+		case <-doneChan:
+			performCleanup(logger)
+			return
+
+		case <-signalChan:
+			performCleanup(logger)
+			return
+
+		case err := <-serverChan:
+			logger.Errorf("Received error of %v", err)
+			return
+		}
+	}
+}
+
+// getAppConfig is the function that takes in the absolute path to the config file, parses the content and returns it.
+func getAppConfig(logger log.Logger, configFilepath string) (*config.Config, error) {
+	configDir := path.Dir(configFilepath)
+	configFilenameWithExt := path.Base(configFilepath)
+
+	splits := strings.FieldsFunc(configFilenameWithExt, func(r rune) bool { return r == '.' })
+	configType := splits[len(splits)-1] // Config file extension
+
+	viper.AddConfigPath(".")
+	viper.AddConfigPath("..")
+	viper.AddConfigPath("$HOME/.op-fault-detector")
+	viper.AddConfigPath(configDir)
+	viper.SetConfigName(configFilenameWithExt)
+	viper.SetConfigType(configType)
+	err := viper.ReadInConfig()
+	if err != nil {
+		return nil, fmt.Errorf("failed to load the config from disk: %w", err)
+	}
+
+	var config config.Config
+	err = viper.Unmarshal(&config)
+	if err != nil {
+		return nil, errors.New("failed to unmarshal config. Verify the 'Config' struct definition in 'pkg/config/config.go'")
+	}
+
+	if err := config.Validate(); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}
+
+func performCleanup(logger log.Logger) {
+	err := apiServer.Stop()
+	if err != nil {
+		logger.Error("Server shutdown not successful: %w", err)
+	}
 }

config.yaml

@@ -0,0 +1,15 @@
+# General system configurations
+system:
+  log_level: "info"
+
+# API related configurations
+api:
+  server:
+    host: "127.0.0.1"
+    port: 8080
+  base_path: "/api"
+  register_versions:
+    - v1
+
+# Faultdetector configurations
+fault_detector:

go.mod

@@ -4,6 +4,10 @@ go 1.21.5
 
 require (
 	github.com/ethereum/go-ethereum v1.13.10
+	github.com/gin-gonic/gin v1.9.1
+	github.com/magiconair/properties v1.8.7
+	github.com/spf13/viper v1.18.2
+	go.uber.org/multierr v1.10.0
 	go.uber.org/zap v1.26.0
 )
 
@@ -12,26 +16,59 @@ require (
 	github.com/StackExchange/wmi v1.2.1 // indirect
 	github.com/bits-and-blooms/bitset v1.10.0 // indirect
 	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
+	github.com/bytedance/sonic v1.10.2 // indirect
+	github.com/chenzhuoyu/base64x v0.0.0-20230717121745-296ad89f973d // indirect
+	github.com/chenzhuoyu/iasm v0.9.1 // indirect
 	github.com/consensys/bavard v0.1.13 // indirect
 	github.com/consensys/gnark-crypto v0.12.1 // indirect
 	github.com/crate-crypto/go-kzg-4844 v0.7.0 // indirect
 	github.com/deckarep/golang-set/v2 v2.1.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.0.1 // indirect
 	github.com/ethereum/c-kzg-4844 v0.4.0 // indirect
+	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
+	github.com/gin-contrib/sse v0.1.0 // indirect
 	github.com/go-ole/go-ole v1.2.5 // 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 v10.17.0 // indirect
+	github.com/goccy/go-json v0.10.2 // indirect
 	github.com/gorilla/websocket v1.4.2 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/holiman/uint256 v1.2.4 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.6 // indirect
+	github.com/leodido/go-urn v1.2.4 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/mmcloughlin/addchain v0.4.0 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.1.1 // indirect
+	github.com/sagikazarmark/locafero v0.4.0 // indirect
+	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
 	github.com/shirou/gopsutil v3.21.4-0.20210419000835-c7a38de76ee5+incompatible // indirect
+	github.com/sourcegraph/conc v0.3.0 // indirect
+	github.com/spf13/afero v1.11.0 // indirect
+	github.com/spf13/cast v1.6.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/subosito/gotenv v1.6.0 // indirect
 	github.com/supranational/blst v0.3.11 // indirect
 	github.com/tklauser/go-sysconf v0.3.12 // indirect
 	github.com/tklauser/numcpus v0.6.1 // indirect
-	go.uber.org/multierr v1.10.0 // indirect
-	golang.org/x/crypto v0.17.0 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.2.12 // indirect
+	golang.org/x/arch v0.7.0 // indirect
+	golang.org/x/crypto v0.18.0 // indirect
 	golang.org/x/exp v0.0.0-20231110203233-9a3e6036ecaa // indirect
 	golang.org/x/mod v0.14.0 // indirect
+	golang.org/x/net v0.20.0 // indirect
 	golang.org/x/sync v0.5.0 // indirect
-	golang.org/x/sys v0.15.0 // indirect
+	golang.org/x/sys v0.16.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
 	golang.org/x/tools v0.15.0 // indirect
+	google.golang.org/protobuf v1.32.0 // indirect
+	gopkg.in/ini.v1 v1.67.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 	rsc.io/tmplfunc v0.0.3 // indirect
 )