Embed templates into Go binary

.golangci.yml

@@ -3,6 +3,7 @@ linters:
   disable:
     - exhaustivestruct
     - funlen
+    - gochecknoglobals
     - ifshort
     - lll
     - nlreturn

internal/app/s3manager/bucket_view.go

@@ -3,16 +3,16 @@ package s3manager
 import (
 	"fmt"
 	"html/template"
+	"io/fs"
 	"net/http"
 	"path"
-	"path/filepath"
 
 	"github.com/matryer/way"
 	minio "github.com/minio/minio-go"
 )
 
 // HandleBucketView shows the details page of a bucket.
-func HandleBucketView(s3 S3, tmplDir string) http.HandlerFunc {
+func HandleBucketView(s3 S3, templates fs.FS) http.HandlerFunc {
 	type objectWithIcon struct {
 		Info minio.ObjectInfo
 		Icon string
@@ -43,9 +43,7 @@ func HandleBucketView(s3 S3, tmplDir string) http.HandlerFunc {
 			Objects:    objs,
 		}
 
-		l := filepath.Join(tmplDir, "layout.html.tmpl")
-		p := filepath.Join(tmplDir, "bucket.html.tmpl")
-		t, err := template.ParseFiles(l, p)
+		t, err := template.ParseFS(templates, "layout.html.tmpl", "bucket.html.tmpl")
 		if err != nil {
 			handleHTTPError(w, fmt.Errorf("error parsing template files: %w", err))
 			return

internal/app/s3manager/bucket_view_test.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"net/http"
 	"net/http/httptest"
+	"os"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -133,9 +134,9 @@ func TestHandleBucketView(t *testing.T) {
 				ListObjectsV2Func: tc.listObjectsV2Func,
 			}
 
-			tmplDir := filepath.Join("..", "..", "..", "web", "template")
+			templates := os.DirFS(filepath.Join("..", "..", "..", "web", "template"))
 			r := way.NewRouter()
-			r.Handle(http.MethodGet, "/buckets/:bucketName", s3manager.HandleBucketView(s3, tmplDir))
+			r.Handle(http.MethodGet, "/buckets/:bucketName", s3manager.HandleBucketView(s3, templates))
 
 			ts := httptest.NewServer(r)
 			defer ts.Close()

internal/app/s3manager/buckets_view.go

@@ -3,22 +3,20 @@ package s3manager
 import (
 	"fmt"
 	"html/template"
+	"io/fs"
 	"net/http"
-	"path/filepath"
 )
 
 // HandleBucketsView renders all buckets on an HTML page.
-func HandleBucketsView(s3 S3, tmplDir string) http.HandlerFunc {
+func HandleBucketsView(s3 S3, templates fs.FS) http.HandlerFunc {
 	return func(w http.ResponseWriter, _ *http.Request) {
 		buckets, err := s3.ListBuckets()
 		if err != nil {
 			handleHTTPError(w, fmt.Errorf("error listing buckets: %w", err))
 			return
 		}
 
-		l := filepath.Join(tmplDir, "layout.html.tmpl")
-		p := filepath.Join(tmplDir, "buckets.html.tmpl")
-		t, err := template.ParseFiles(l, p)
+		t, err := template.ParseFS(templates, "layout.html.tmpl", "buckets.html.tmpl")
 		if err != nil {
 			handleHTTPError(w, fmt.Errorf("error parsing template files: %w", err))
 			return

internal/app/s3manager/buckets_view_test.go

@@ -4,6 +4,7 @@ import (
 	"io"
 	"net/http"
 	"net/http/httptest"
+	"os"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -59,13 +60,13 @@ func TestHandleBucketsView(t *testing.T) {
 				ListBucketsFunc: tc.listBucketsFunc,
 			}
 
-			tmplDir := filepath.Join("..", "..", "..", "web", "template")
+			templates := os.DirFS(filepath.Join("..", "..", "..", "web", "template"))
 
 			req, err := http.NewRequest(http.MethodGet, "/buckets", nil)
 			is.NoErr(err)
 
 			rr := httptest.NewRecorder()
-			handler := s3manager.HandleBucketsView(s3, tmplDir)
+			handler := s3manager.HandleBucketsView(s3, templates)
 
 			handler.ServeHTTP(rr, req)
 			resp := rr.Result()

main.go

@@ -2,11 +2,12 @@ package main
 
 import (
 	"crypto/tls"
+	"embed"
 	"fmt"
+	"io/fs"
 	"log"
 	"net/http"
 	"os"
-	"path/filepath"
 	"strconv"
 
 	"github.com/mastertinner/adapters/logging"
@@ -15,6 +16,9 @@ import (
 	minio "github.com/minio/minio-go"
 )
 
+//go:embed web/template
+var templateFS embed.FS
+
 func main() {
 	endpoint, ok := os.LookupEnv("ENDPOINT")
 	if !ok {
@@ -35,7 +39,11 @@ func main() {
 		port = "8080"
 	}
 
-	tmplDir := filepath.Join("web", "template")
+	// Set up templates
+	templates, err := fs.Sub(templateFS, "web/template")
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	// Set up S3 client
 	s3, err := minio.New(endpoint, accessKeyID, secretAccessKey, useSSL)
@@ -49,8 +57,8 @@ func main() {
 	// Set up router
 	r := way.NewRouter()
 	r.Handle(http.MethodGet, "/", http.RedirectHandler("/buckets", http.StatusPermanentRedirect))
-	r.Handle(http.MethodGet, "/buckets", s3manager.HandleBucketsView(s3, tmplDir))
-	r.Handle(http.MethodGet, "/buckets/:bucketName", s3manager.HandleBucketView(s3, tmplDir))
+	r.Handle(http.MethodGet, "/buckets", s3manager.HandleBucketsView(s3, templates))
+	r.Handle(http.MethodGet, "/buckets/:bucketName", s3manager.HandleBucketView(s3, templates))
 	r.Handle(http.MethodPost, "/api/buckets", s3manager.HandleCreateBucket(s3))
 	r.Handle(http.MethodDelete, "/api/buckets/:bucketName", s3manager.HandleDeleteBucket(s3))
 	r.Handle(http.MethodPost, "/api/buckets/:bucketName/objects", s3manager.HandleCreateObject(s3))