Refactor database login into a separate module

fileupload.go

@@ -1,33 +1,22 @@
 package rushlink
 
 import (
-	"encoding/hex"
-	"hash/crc32"
-	"io"
 	"log"
 	"net/http"
-	"net/url"
-	"os"
-	"path"
 
-	"github.com/google/uuid"
 	"github.com/pkg/errors"
-	bolt "go.etcd.io/bbolt"
 )
 
-// Use the Castagnoli checksum because of the acceleration on Intel CPUs
-var checksumTable = crc32.MakeTable(crc32.Castagnoli)
-
 // Where to store the uploaded files
 var fileStoreDir = ""
 
-// Custom HTTP filesystem handler
-type fileUploadFileSystem struct {
+// FileUploadFileSystem is a HTTP filesystem handler
+type FileUploadFileSystem struct {
 	fs http.FileSystem
 }
 
-// Open opens file
-func (fs fileUploadFileSystem) Open(path string) (http.File, error) {
+// Open opens a file
+func (fs FileUploadFileSystem) Open(path string) (http.File, error) {
 	log.Println(path)
 	file, err := fs.fs.Open(path)
 	if err != nil {
@@ -42,153 +31,3 @@ func (fs fileUploadFileSystem) Open(path string) (http.File, error) {
 	}
 	return file, nil
 }
-
-type fileUploadState int
-
-type fileUpload struct {
-	State       fileUploadState
-	ID          uuid.UUID
-	FileName    string
-	ContentType string
-	Checksum    uint32
-}
-
-const (
-	dirMode  os.FileMode = 0750
-	fileMode os.FileMode = 0640
-)
-
-const (
-	fileUploadStateUndef   fileUploadState = 0
-	fileUploadStatePresent                 = 1
-	fileUploadStateDeleted                 = 2
-)
-
-func (t fileUploadState) String() string {
-	switch t {
-	case fileUploadStateUndef:
-		return "unknown"
-	case fileUploadStatePresent:
-		return "present"
-	case fileUploadStateDeleted:
-		return "deleted"
-	default:
-		return "invalid"
-	}
-}
-
-func OpenFileStore(path string) error {
-	if path == "" {
-		return errors.New("file-store not set")
-	}
-
-	// Try to create the file store directory if it does not yet exist
-	if err := os.MkdirAll(path, dirMode); err != nil {
-		return errors.Wrap(err, "creating file store directory")
-	}
-
-	fileStoreDir = path[:]
-	return nil
-}
-
-func newFileUpload(tx *bolt.Tx, r io.Reader, fileName string, contentType string) (*fileUpload, error) {
-	id, err := uuid.NewRandom()
-	if err != nil {
-		return nil, errors.Wrap(err, "generating UUID")
-	}
-
-	filePath := fileStorePath(id, fileName)
-	if err := os.Mkdir(path.Dir(filePath), dirMode); err != nil {
-		return nil, errors.Wrap(err, "creating file dir")
-	}
-	file, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE, fileMode)
-	if err != nil {
-		return nil, errors.Wrap(err, "opening file")
-	}
-	defer file.Close()
-
-	hash := crc32.New(checksumTable)
-	tee := io.TeeReader(r, hash)
-	_, err = io.Copy(file, tee)
-	if err != nil {
-		return nil, errors.Wrap(err, "writing to file")
-	}
-
-	fu := &fileUpload{
-		State:       fileUploadStatePresent,
-		ID:          id,
-		FileName:    fileName,
-		ContentType: contentType,
-		Checksum:    hash.Sum32(),
-	}
-	if err := fu.save(tx); err != nil {
-		return nil, err
-	}
-	return fu, nil
-}
-
-func getFileUpload(tx *bolt.Tx, id uuid.UUID) (*fileUpload, error) {
-	bucket := tx.Bucket([]byte(BUCKET_FILE_UPLOAD))
-	if bucket == nil {
-		return nil, errors.Errorf("bucket %v does not exist", BUCKET_FILE_UPLOAD)
-	}
-	storedBytes := bucket.Get(id[:])
-	if storedBytes == nil {
-		return nil, nil
-	}
-	fu := &fileUpload{}
-	err := Unmarshal(storedBytes, fu)
-	return fu, err
-}
-
-func (fu *fileUpload) save(tx *bolt.Tx) error {
-	bucket := tx.Bucket([]byte(BUCKET_FILE_UPLOAD))
-	if bucket == nil {
-		return errors.Errorf("bucket %v does not exist", BUCKET_FILE_UPLOAD)
-	}
-
-	buf, err := Marshal(fu)
-	if err != nil {
-		return errors.Wrap(err, "encoding for database failed")
-	}
-	if err := bucket.Put(fu.ID[:], buf); err != nil {
-		return errors.Wrap(err, "database transaction failed")
-	}
-	return nil
-}
-
-func (fu *fileUpload) delete(tx *bolt.Tx) error {
-	// Remove the file in the backend
-	filePath := fileStorePath(fu.ID, fu.FileName)
-	if err := os.Remove(filePath); err != nil {
-		return err
-	}
-
-	// Update the file in the server
-	if err := (&fileUpload{
-		ID:    fu.ID,
-		State: fileUploadStateDeleted,
-	}).save(tx); err != nil {
-		return err
-	}
-
-	// Cleanup the parent directory
-	wrap := "deletion succeeded, but removing the file directory has failed"
-	return errors.Wrap(os.Remove(path.Dir(filePath)), wrap)
-}
-
-func (fu *fileUpload) url() *url.URL {
-	rawurl := "/uploads/" + hex.EncodeToString(fu.ID[:]) + "/" + fu.FileName
-	urlParse, err := url.Parse(rawurl)
-	if err != nil {
-		panic("could not construct /uploads/ url")
-	}
-	return urlParse
-}
-
-func fileStorePath(id uuid.UUID, fileName string) string {
-	if fileStoreDir == "" {
-		panic("fileStoreDir called while the file store path has not been set")
-	}
-	return path.Join(fileStoreDir, hex.EncodeToString(id[:]), fileName)
-}