refactor: move config related code into dedicated package

internal/config/config.go

@@ -0,0 +1,129 @@
+package config
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/google/uuid"
+	log "github.com/sirupsen/logrus"
+	"github.com/spf13/viper"
+)
+
+const (
+	ServerHostname   = "server.hostname"
+	DatabaseHost     = "database.host"
+	DatabaseName     = "database.name"
+	DatabaseUser     = "database.user"
+	DatabasePassword = "database.password"
+	DatabasePort     = "database.port"
+	DatabaseSslMode  = "database.sslmode"
+
+	SecurityTokenExpiration = "security.token_expiration"
+	SecuritySecret          = "security.secret"
+
+	QueueBroker = "queue.broker"
+	QueueStore  = "queue.store"
+
+	SmtpFrom       = "smtp.from"
+	SmtpHost       = "smtp.host"
+	SmtpPort       = "smtp.port"
+	SmtpUsername   = "smtp.username"
+	SmtpPassword   = "smtp.password"
+	SmtpSkipVerify = "false"
+)
+
+var defaults = map[string]string{
+	ServerHostname:          "0.0.0.0:3333",
+	DatabaseHost:            "127.0.0.1",
+	DatabaseName:            "taskcafe",
+	DatabaseUser:            "taskcafe",
+	DatabasePassword:        "taskcafe_test",
+	DatabasePort:            "5432",
+	DatabaseSslMode:         "disable",
+	SecurityTokenExpiration: "15m",
+	SecuritySecret:          "",
+	QueueBroker:             "amqp://guest:guest@localhost:5672/",
+	QueueStore:              "memcache://localhost:11211",
+	SmtpFrom:                "no-reply@example.com",
+	SmtpHost:                "localhost",
+	SmtpPort:                "587",
+	SmtpUsername:            "",
+	SmtpPassword:            "",
+	SmtpSkipVerify:          "false",
+}
+
+func InitDefaults() {
+	for key, value := range defaults {
+		viper.SetDefault(key, value)
+	}
+}
+
+func GetDatabaseConnectionUri() string {
+	connection := fmt.Sprintf("user=%s password=%s host=%s dbname=%s port=%s sslmode=%s",
+		viper.GetString(DatabaseUser),
+		viper.GetString(DatabasePassword),
+		viper.GetString(DatabaseHost),
+		viper.GetString(DatabaseName),
+		viper.GetString(DatabasePort),
+		viper.GetString(DatabaseSslMode),
+	)
+	return connection
+}
+
+type AppConfig struct {
+	Email    EmailConfig
+	Security SecurityConfig
+}
+
+type EmailConfig struct {
+	Host               string
+	Port               int
+	From               string
+	Username           string
+	Password           string
+	SiteURL            string
+	InsecureSkipVerify bool
+}
+
+type SecurityConfig struct {
+	AccessTokenExpiration time.Duration
+	Secret                []byte
+}
+
+func GetAppConfig() (AppConfig, error) {
+	secret := viper.GetString(SecuritySecret)
+	if strings.TrimSpace(secret) == "" {
+		log.Warn("server.secret is not set, generating a random secret")
+		secret = uuid.New().String()
+	}
+	securityCfg, err := GetSecurityConfig(viper.GetString(SecurityTokenExpiration), []byte(secret))
+	if err != nil {
+		return AppConfig{}, err
+	}
+	emailCfg := GetEmailConfig()
+	return AppConfig{
+		Email:    emailCfg,
+		Security: securityCfg,
+	}, nil
+}
+
+func GetSecurityConfig(accessTokenExp string, secret []byte) (SecurityConfig, error) {
+	exp, err := time.ParseDuration(accessTokenExp)
+	if err != nil {
+		log.WithError(err).Error("issue parsing duration")
+		return SecurityConfig{}, err
+	}
+	return SecurityConfig{AccessTokenExpiration: exp, Secret: secret}, nil
+}
+
+func GetEmailConfig() EmailConfig {
+	return EmailConfig{
+		From:               viper.GetString("smtp.from"),
+		Host:               viper.GetString("smtp.host"),
+		Port:               viper.GetInt("smtp.port"),
+		Username:           viper.GetString("smtp.username"),
+		Password:           viper.GetString("smtp.password"),
+		InsecureSkipVerify: viper.GetBool("smtp.skip_verify"),
+	}
+}