feat: added server configuration using env vars

cmd/bazaar/main.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"context"
+
 	"github.com/fmartingr/bazaar/internal/server"
 	"github.com/fmartingr/bazaar/pkg/manager"
 	"github.com/fmartingr/bazaar/pkg/shop/akiracomics"
@@ -20,11 +22,11 @@ func main() {
 	m.Register(gtmstore.Domains, gtmstore.NewGTMStoreShopFactory())
 	m.Register(casadellibro.Domains, casadellibro.NewCasaDelLibroShopFactory())
 
-	server := server.NewServer(server.ServerConf{
-		HttpPort: 8080,
-	}, &m)
+	ctx := context.Background()
 
-	server.Start()
+	server := server.NewServer(server.ParseServerConfiguration(ctx), &m)
+
+	server.Start(ctx)
 
 	server.WaitStop()
 }

go.mod

@@ -5,6 +5,7 @@ go 1.19
 require (
 	github.com/PuerkitoBio/goquery v1.8.0
 	github.com/goodsign/monday v1.0.0
+	github.com/sethvargo/go-envconfig v0.8.2
 	github.com/stretchr/testify v1.8.0
 )
 

go.sum

@@ -7,8 +7,11 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/goodsign/monday v1.0.0 h1:Yyk/s/WgudMbAJN6UWSU5xAs8jtNewfqtVblAlw0yoc=
 github.com/goodsign/monday v1.0.0/go.mod h1:r4T4breXpoFwspQNM+u2sLxJb2zyTaxVGqUfTBjWOu8=
+github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sethvargo/go-envconfig v0.8.2 h1:DDUVuG21RMgeB/bn4leclUI/837y6cQCD4w8hb5797k=
+github.com/sethvargo/go-envconfig v0.8.2/go.mod h1:Iz1Gy1Sf3T64TQlJSvee81qDhf7YIlt8GMUX6yyNFs0=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=

internal/server/config.go

@@ -0,0 +1,64 @@
+package server
+
+import (
+	"bufio"
+	"context"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/sethvargo/go-envconfig"
+)
+
+// readDotEnv reads the configuration from variables in a .env file (only for contributing)
+func readDotEnv() map[string]string {
+	file, err := os.Open(".env")
+	if err != nil {
+		return nil
+	}
+	defer file.Close()
+
+	result := make(map[string]string)
+
+	scanner := bufio.NewScanner(file)
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		keyval := strings.SplitN(line, "=", 2)
+		result[keyval[0]] = keyval[1]
+	}
+
+	if err := scanner.Err(); err != nil {
+		log.Fatal(err)
+	}
+
+	return result
+}
+
+type ServerConfig struct {
+	Hostname string `env:"HOSTNAME,required"`
+	Http     struct {
+		Enabled bool `env:"HTTP_ENABLED,default=True"`
+		Port    int  `env:"HTTP_PORT,default=8080"`
+	}
+}
+
+func ParseServerConfiguration(ctx context.Context) *ServerConfig {
+	var cfg ServerConfig
+
+	lookuper := envconfig.MultiLookuper(
+		envconfig.MapLookuper(map[string]string{"HOSTNAME": os.Getenv("HOSTNAME")}),
+		envconfig.MapLookuper(readDotEnv()),
+		envconfig.PrefixLookuper("BAZAAR_", envconfig.OsLookuper()),
+		envconfig.OsLookuper(),
+	)
+	if err := envconfig.ProcessWith(ctx, &cfg, lookuper); err != nil {
+		log.Fatalf("Error parsing configuration: %s", err)
+	}
+
+	return &cfg
+}

internal/server/server.go

@@ -14,25 +14,24 @@ import (
 	"github.com/fmartingr/bazaar/pkg/manager"
 )
 
-type ServerConf struct {
-	HttpPort int
-}
-
 type Server struct {
-	http internalModels.Server
+	Http   internalModels.Server
+	config *ServerConfig
 
 	cancel context.CancelFunc
 }
 
-func (s *Server) Start() error {
-	ctx, cancel := context.WithCancel(context.Background())
+func (s *Server) Start(ctx context.Context) error {
+	ctx, cancel := context.WithCancel(ctx)
 	s.cancel = cancel
 
-	go func() {
-		if err := s.http.Start(ctx); err != nil && !errors.Is(err, http.ErrServerClosed) {
-			log.Fatalf("error starting server: %s", err)
-		}
-	}()
+	if s.config.Http.Enabled {
+		go func() {
+			if err := s.Http.Start(ctx); err != nil && !errors.Is(err, http.ErrServerClosed) {
+				log.Fatalf("error starting server: %s", err)
+			}
+		}()
+	}
 
 	return nil
 }
@@ -53,15 +52,22 @@ func (s *Server) Stop() error {
 	shuwdownContext, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()
 
-	if err := s.http.Stop(shuwdownContext); err != nil && !errors.Is(err, http.ErrServerClosed) {
-		log.Fatalf("error shutting down http server: %s", err)
+	if s.config.Http.Enabled {
+		if err := s.Http.Stop(shuwdownContext); err != nil && !errors.Is(err, http.ErrServerClosed) {
+			log.Fatalf("error shutting down http server: %s", err)
+		}
 	}
 
 	return nil
 }
 
-func NewServer(serverConf ServerConf, m *manager.Manager) *Server {
-	return &Server{
-		http: NewHttpServer(serverConf.HttpPort, m),
+func NewServer(conf *ServerConfig, m *manager.Manager) *Server {
+	server := &Server{
+		config: conf,
 	}
+	if conf.Http.Enabled {
+		server.Http = NewHttpServer(conf.Http.Port, m)
+	}
+
+	return server
 }