Added skeleton code for register endpoint (#2)

Reviewed-on: phoenix/textsender-auth#2
Co-authored-by: phoenix <kundeng00@pm.me>
Co-committed-by: phoenix <kundeng00@pm.me>

internal/config/config.go

@@ -0,0 +1,107 @@
+package config
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+
+	"github.com/joho/godotenv"
+)
+
+type Config struct {
+	DBConnString string
+	ServerPort   string
+	ResetDB      bool
+}
+
+type ConnectionInfo struct {
+	Username string
+	Password string
+	Database string
+	Host     string
+	Port     int
+	SslMode  string
+}
+
+const Port = "9080"
+
+func (ci ConnectionInfo) Parse() string {
+	return fmt.Sprintf("postgres://%s:%s@%s:%d/%s?sslmode=%s", ci.Username, ci.Password, ci.Host, ci.Port, ci.Database, ci.SslMode)
+}
+
+func Load() *Config {
+	resetDb := flag.Bool("reset-db", false, "Reset the database schema and exit")
+	port := flag.String("port", Port, "Server port")
+	flag.Parse()
+
+	err := godotenv.Load()
+	if err != nil {
+		log.Fatal("Error loading .env file")
+	}
+
+	unpackedConnString := unpackDBConnString()
+	dbConnString := unpackedConnString.Parse()
+
+	return &Config{
+		DBConnString: dbConnString,
+		ServerPort:   *port,
+		ResetDB:      *resetDb,
+	}
+}
+
+func unpackDBConnString() (connInfo ConnectionInfo) {
+	username := os.Getenv("DB_USER")
+	password := os.Getenv("DB_PASSWORD")
+	host := os.Getenv("DB_HOST")
+	port := os.Getenv("DB_PORT")
+	database := os.Getenv("DB_NAME")
+	sslMode := os.Getenv("DB_SSLMODE")
+
+	if username != "" {
+		connInfo.Username = username
+	} else {
+		connInfo.Username = "user"
+	}
+
+	if password != "" {
+		connInfo.Password = password
+	} else {
+		connInfo.Password = "password"
+	}
+
+	if host != "" {
+		connInfo.Host = host
+	} else {
+		connInfo.Host = "localhost"
+	}
+
+	if port != "" {
+		num, err := strconv.Atoi(port)
+		if err != nil {
+			return
+		}
+		connInfo.Port = num
+	} else {
+		connInfo.Port = 5432
+	}
+
+	if database != "" {
+		connInfo.Database = database
+	} else {
+		connInfo.Database = "textsender_auth_db"
+	}
+
+	if sslMode != "" {
+		connInfo.SslMode = sslMode
+	} else {
+		connInfo.SslMode = "disable"
+	}
+
+	return
+}
+
+func (c *Config) GetDBConnString() string {
+	return c.DBConnString
+}