initial commit

routes/file.go

@@ -0,0 +1,204 @@
+package routes
+
+import (
+	"bytes"
+	"crypto/md5"
+	"database/sql"
+	"errors"
+	"fmt"
+	"foobar/database"
+	"foobar/model"
+	"io"
+	"mime/multipart"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+var maxFileSize int64 = 32 * 1000 * 1000
+
+func fileUpload(w http.ResponseWriter, r *http.Request) (redirectURL, error) {
+
+	boxURL, err := GetBoxURL(r)
+	if err != nil {
+		return noRedirect, err
+	}
+
+	tx := database.MustBeginTx()
+	defer tx.Rollback()
+
+	box, err := database.SelectBox(boxURL)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) { // this is a new URL the user wants to claim for themselves
+			editCode := r.FormValue("edit_code")
+			if editCode == "" {
+				return noRedirect, newUserError(
+					"Missing edit code. Box can't be created without it",
+				)
+			}
+			var (
+				id            = uuid.New()
+				createdAt     = time.Now()
+				lastUpdatedAt = createdAt
+				header        = readmeTemplate
+			)
+			newBox := model.NewBox(
+				id, boxURL, editCode, header, false, false, createdAt, lastUpdatedAt,
+			)
+			err = database.InsertBox(tx, newBox, editCode, header)
+			if err != nil {
+				return noRedirect, err
+			}
+			box = newBox
+		} else {
+			return noRedirect, err
+		}
+	}
+
+	filesCtx, err := GetFilesFromUploadRequest(r)
+	if err != nil {
+		return noRedirect, err
+	}
+
+	var files []model.File
+
+	for _, file := range filesCtx {
+
+		bytes, err := readFileBytes(file.FileHeader())
+		if err != nil {
+			return noRedirect, err
+		}
+
+		mime := model.FileMime(http.DetectContentType(bytes))
+
+		if file.Filename() == "README.md" {
+
+			editCode := r.FormValue("edit_code")
+			if editCode == "" {
+				return noRedirect, newUserError(
+					"Missing edit code. README can't be updated. " +
+						"If you're not attempting to update the header, we'd " +
+						"suggest changing \"README.md\" to a new filename.",
+				)
+			}
+
+			if editCode != box.EditCode() {
+				return noRedirect, newUserError(
+					"Wrong edit code.",
+				)
+			}
+
+			md := mdToHTML(bytes)
+
+			err := database.UpdateHeader(tx, box.ID(), md)
+			if err != nil {
+				return noRedirect, err
+			}
+
+			if err := tx.Commit(); err != nil {
+				return noRedirect, err
+			}
+
+			// FIXME: we're ignoring all other uploaded files
+			return redirectURL(fmt.Sprintf("/box/%s", box.Url())), nil
+
+		} else {
+
+			err = copyBytesToDisk(file.ID(), bytes)
+			if err != nil {
+				return "", err
+			}
+
+			checksum := calculateMD5(bytes)
+
+			newFile := model.NewFile(
+				file.ID(), file.Filename(), file.Size(),
+				file.UploadedDate(), mime, checksum,
+			)
+
+			files = append(files, newFile)
+		}
+	}
+
+	for _, file := range files {
+		err = database.InsertFile(tx, box.ID(), file)
+		if err != nil {
+			return noRedirect, err
+		}
+	}
+
+	if err = tx.Commit(); err != nil {
+		return noRedirect, err
+	}
+
+	return redirectURL(fmt.Sprintf("/box/%s/inside", box.Url())), nil
+}
+
+func calculateMD5(fileBytes []byte) model.MD5Checksum {
+	return md5.Sum(fileBytes)
+}
+
+func readFileBytes(fileHeader *multipart.FileHeader) ([]byte, error) {
+	fileReader, err := fileHeader.Open()
+	if err != nil {
+		panic(err)
+	}
+	defer fileReader.Close()
+
+	fileBytes, err := io.ReadAll(fileReader)
+	if err != nil {
+		return nil, err
+	}
+	return fileBytes, nil
+}
+
+func copyBytesToDisk(fileId uuid.UUID, fileBytes []byte) error {
+	fileWriter, err := os.Create(filepath.Join(
+		staticDir, "box", fmt.Sprintf(fileId.String())),
+	)
+	if err != nil {
+		return err
+	}
+	defer fileWriter.Close()
+
+	_, err = io.Copy(fileWriter, bytes.NewReader(fileBytes))
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func GetFilesFromUploadRequest(r *http.Request) ([]model.FileUploadContext, error) {
+
+	err := r.ParseMultipartForm(int64(maxFileSize))
+	if err != nil {
+		return nil, err
+	}
+
+	headers, ok := r.MultipartForm.File["file"]
+	if !ok {
+		return nil, newUserError("no file")
+	}
+
+	var (
+		files []model.FileUploadContext
+	)
+
+	for _, header := range headers {
+		var (
+			id           = uuid.New()
+			uploadedDate = time.Now()
+			size         = header.Size
+			filename     = model.Filename(header.Filename)
+			mime         = model.MimeFromHeader(header.Header)
+		)
+
+		fileUpload := model.NewFileUploadContext(id, uploadedDate, size, filename, mime, header)
+		files = append(files, fileUpload)
+	}
+	return files, nil
+
+}