Expire files

expire all unauthenticated uploads quickly by default

Closes: #5

server/config.go

@@ -21,6 +21,9 @@ func (c ProducerListenConfig) Addr() string {
 type ProducerUploadConfig struct {
 	BodyLimit int    `envkey:"BODY_LIMIT" default:"1073741824"`
 	BaseURL   string `envkey:"BASE_URL"`
+	// Default expiration time in seconds
+	DefaultExpirationTime int    `envkey:"DEFAULT_EXPIRATION_TIME" default:"1800"`
+	AdminToken            string `envkey:"ADMIN_TOKEN"`
 }
 
 type ProducerS3Config struct {

server/files.go

@@ -4,13 +4,15 @@ package server
 
 import (
 	"context"
+	"crypto/subtle"
 	"errors"
 	"fmt"
 	"io"
 	"mime/multipart"
 	"net/url"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/danielgtaylor/huma/v2"
 	"github.com/gabriel-vasile/mimetype"
@@ -22,13 +24,32 @@ type UploadData struct {
 }
 
 type UploadInput struct {
+	Auth    string `header:"Authorization"`
+	Expires int64  `header:"Expires"`
 	RawBody huma.MultipartFormFiles[UploadData]
 }
 
 type UploadOutput struct {
 	Body struct {
-		ID  string `json:"id"`
-		URL string `json:"url"`
+		ID      string `json:"id"`
+		URL     string `json:"url"`
+		Expires int    `json:"expires"`
+	}
+}
+
+var BEARER_PREFIX = "Bearer "
+
+func isAuthenticated(authorization string) bool {
+	if CONFIG.Upload.AdminToken == "" {
+		return false
+	}
+
+	if authorization[:len(BEARER_PREFIX)] == BEARER_PREFIX {
+		header_token := authorization[len(BEARER_PREFIX):]
+
+		return subtle.ConstantTimeCompare([]byte(header_token), []byte(CONFIG.Upload.AdminToken)) == 1
+	} else {
+		return false
 	}
 }
 
@@ -52,14 +73,20 @@ func Upload(ctx context.Context, input *UploadInput) (*UploadOutput, error) {
 	mime := mimetype.Detect(det_buf[:n])
 	fd.Seek(0, 0)
 
-	err = UploadToS3(ctx, fd, file_id.String(), file.Filename, file.Size, mime.String())
+	expires := time.Now().Add(time.Duration(CONFIG.Upload.DefaultExpirationTime) * time.Second)
+	if isAuthenticated(input.Auth) {
+		expires = time.Unix(input.Expires, 0)
+	}
+
+	err = UploadToS3(ctx, fd, file_id.String(), file.Filename, file.Size, mime.String(), expires)
 	if err != nil {
 		return nil, err
 	}
 
 	resp := &UploadOutput{}
 	resp.Body.ID = file_id.String()
 	resp.Body.URL = fmt.Sprintf("%s/%s", CONFIG.Upload.BaseURL, file_id.String())
+	resp.Body.Expires = int(expires.Unix())
 
 	return resp, nil
 }

server/producer_test.go

@@ -11,6 +11,7 @@ import (
 	"net/url"
 	"regexp"
 	"testing"
+	"time"
 
 	"github.com/danielgtaylor/huma/v2/humatest"
 	"github.com/gabriel-vasile/mimetype"
@@ -67,6 +68,12 @@ func TestUploadDownload(t *testing.T) {
 	filename := "test file"
 	upload_data := uploadData(t, api, test_data, filename)
 
+	expected_expires := time.Now().Add(time.Duration(CONFIG.Upload.DefaultExpirationTime) * time.Second).Unix()
+
+	if expected_expires+1 < int64(upload_data.Body.Expires) || expected_expires-1 > int64(upload_data.Body.Expires) {
+		t.Fatalf("Expected expire value of %d (+-1), found %d", expected_expires, upload_data.Body.Expires)
+	}
+
 	path := fmt.Sprintf("/%s", upload_data.Body.ID)
 	resp := assertRespCode(t, api.Get(path), 200)
 

server/s3.go

@@ -6,6 +6,7 @@ package server
 import (
 	"context"
 	"io"
+	"time"
 
 	"github.com/minio/minio-go/v7"
 	"github.com/minio/minio-go/v7/pkg/credentials"
@@ -19,7 +20,7 @@ func getS3Client() (*minio.Client, error) {
 	return client, err
 }
 
-func UploadToS3(ctx context.Context, file io.Reader, file_id string, filename string, filesize int64, content_type string) error {
+func UploadToS3(ctx context.Context, file io.Reader, file_id string, filename string, filesize int64, content_type string, expires time.Time) error {
 	client, err := getS3Client()
 	if err != nil {
 		return err
@@ -35,6 +36,7 @@ func UploadToS3(ctx context.Context, file io.Reader, file_id string, filename st
 				"Filename": filename,
 				"Type":     content_type,
 			},
+			Expires: expires,
 		},
 	)
 	getLogger().Printf("upload info: %+v\n", info)