xtablo-source/backend/internal/web/handlers_files.go
Arthur Belleville 4ea4d28e6e
fix(07): WR-05 sanitize upload filename with filepath.Base and length cap
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
2026-05-15 18:56:11 +02:00

332 lines
12 KiB
Go

package web
import (
"context"
"errors"
"log/slog"
"net/http"
"path/filepath"
"strconv"
"strings"
"time"
"backend/internal/auth"
"backend/internal/db/sqlc"
"backend/internal/files"
"backend/templates"
"github.com/go-chi/chi/v5"
"github.com/google/uuid"
"github.com/gorilla/csrf"
"github.com/jackc/pgx/v5"
)
// FileStorer is the interface satisfied by files.Store and used for test injection.
// Aliased here so web package can reference it without importing internal/files in tests.
type FileStorer = files.FileStorer
// FilesDeps holds dependencies for all file handlers.
type FilesDeps struct {
Queries *sqlc.Queries
Files FileStorer // interface — allows stub injection in tests
MaxUploadMB int // parsed from MAX_UPLOAD_SIZE_MB env var (default 25)
}
// loadOwnedTabloForFile is the shared preamble for all /tablos/{id}/files/{file_id}*
// handlers. It calls loadOwnedTablo for tablo ownership verification, then parses
// the {file_id} URL param and fetches the file (verifying it belongs to the tablo).
// Returns (tablo, file, user, true) on success. On failure it writes the appropriate
// HTTP response and returns false; callers must return immediately.
func loadOwnedTabloForFile(w http.ResponseWriter, r *http.Request, deps FilesDeps) (sqlc.Tablo, sqlc.TabloFile, *auth.User, bool) {
tablo, user, ok := loadOwnedTablo(w, r, TablosDeps{Queries: deps.Queries})
if !ok {
return sqlc.Tablo{}, sqlc.TabloFile{}, nil, false
}
fileID, err := uuid.Parse(chi.URLParam(r, "file_id"))
if err != nil {
http.NotFound(w, r)
return sqlc.Tablo{}, sqlc.TabloFile{}, nil, false
}
file, err := deps.Queries.GetTabloFileByID(r.Context(), sqlc.GetTabloFileByIDParams{
ID: fileID,
TabloID: tablo.ID,
})
if err != nil {
if errors.Is(err, pgx.ErrNoRows) {
http.NotFound(w, r)
return sqlc.Tablo{}, sqlc.TabloFile{}, nil, false
}
slog.Default().Error("files: GetTabloFileByID failed", "id", fileID, "err", err)
http.Error(w, "internal server error", http.StatusInternalServerError)
return sqlc.Tablo{}, sqlc.TabloFile{}, nil, false
}
return tablo, file, user, true
}
// TabloFilesTabHandler handles GET /tablos/{id}/files.
// Returns the FilesTabFragment for HTMX requests or the full TabloDetailPage otherwise.
//
// Security: deps.Files nil guard is the FIRST statement (T-05-02-06).
// Ownership enforced by loadOwnedTablo (T-05-02-04).
func TabloFilesTabHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if deps.Files == nil {
http.Error(w, "storage not configured", http.StatusServiceUnavailable)
return
}
tablo, user, ok := loadOwnedTablo(w, r, TablosDeps{Queries: deps.Queries})
if !ok {
return
}
fileList, err := deps.Queries.ListFilesByTablo(r.Context(), tablo.ID)
if err != nil {
slog.Default().Error("files tab: ListFilesByTablo failed", "tablo_id", tablo.ID, "err", err)
fileList = []sqlc.TabloFile{}
}
if fileList == nil {
fileList = []sqlc.TabloFile{}
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
if r.Header.Get("HX-Request") == "true" {
_ = templates.FilesTabFragment(tablo, fileList, csrf.Token(r)).Render(r.Context(), w)
return
}
_ = templates.TabloDetailPage(user, csrf.Token(r), tablo, nil, fileList, "files").Render(r.Context(), w)
}
}
// TabloTasksTabHandler handles GET /tablos/{id}/tasks (Tasks tab entry point).
// Returns the TasksTabFragment for HTMX requests or the full TabloDetailPage otherwise.
// Lives here (not handlers_tasks.go) because it is part of the tab wiring introduced
// in Phase 5 alongside FilesTabHandler.
func TabloTasksTabHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
tablo, user, ok := loadOwnedTablo(w, r, TablosDeps{Queries: deps.Queries})
if !ok {
return
}
tasks, err := deps.Queries.ListTasksByTablo(r.Context(), tablo.ID)
if err != nil {
slog.Default().Error("tasks tab: ListTasksByTablo failed", "tablo_id", tablo.ID, "err", err)
tasks = []sqlc.Task{}
}
if tasks == nil {
tasks = []sqlc.Task{}
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
if r.Header.Get("HX-Request") == "true" {
_ = templates.TasksTabFragment(tablo, tasks, csrf.Token(r)).Render(r.Context(), w)
return
}
_ = templates.TabloDetailPage(user, csrf.Token(r), tablo, tasks, nil, "tasks").Render(r.Context(), w)
}
}
// FileUploadHandler handles POST /tablos/{id}/files.
// Accepts a multipart file, streams it to S3 via deps.Files.Upload, inserts a
// tablo_files row, and returns the updated file list fragment (HTMX) or redirects (non-HTMX).
//
// Security invariants:
// - deps.Files nil guard is the FIRST statement before reading any request body (T-05-02-06)
// - r.Body wrapped with http.MaxBytesReader BEFORE ParseMultipartForm (T-05-02-02, Pitfall 2)
// - filename stored as display string only; S3 key is "files/{uuid}" — never reaches FS (T-05-02-01, D-04)
// - content-type sniffed server-side by files.Store.Upload (T-05-02-03, D-05)
// - tablo ownership verified by loadOwnedTablo (T-05-02-04, FILE-06)
func FileUploadHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if deps.Files == nil {
http.Error(w, "storage not configured", http.StatusServiceUnavailable)
return
}
tablo, _, ok := loadOwnedTablo(w, r, TablosDeps{Queries: deps.Queries})
if !ok {
return
}
maxBytes := int64(deps.MaxUploadMB) * 1024 * 1024
r.Body = http.MaxBytesReader(w, r.Body, maxBytes) // MUST be before ParseMultipartForm (Pitfall 2)
if err := r.ParseMultipartForm(2 << 20); err != nil {
var mbErr *http.MaxBytesError
if errors.As(err, &mbErr) {
// Re-list files so the error fragment shows the current list.
fileList, _ := deps.Queries.ListFilesByTablo(r.Context(), tablo.ID)
if fileList == nil {
fileList = []sqlc.TabloFile{}
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.WriteHeader(http.StatusUnprocessableEntity)
errMsg := "File too large (max " + strconv.Itoa(deps.MaxUploadMB) + " MB)."
_ = templates.UploadErrorFragment(tablo, fileList, csrf.Token(r), errMsg).Render(r.Context(), w)
return
}
http.Error(w, "bad request", http.StatusBadRequest)
return
}
file, header, err := r.FormFile("file")
if err != nil {
http.Error(w, "bad request: missing file field", http.StatusBadRequest)
return
}
defer file.Close()
filename := strings.TrimSpace(header.Filename)
if filename == "" {
http.Error(w, "bad request: file must have a filename", http.StatusBadRequest)
return
}
// Sanitize: strip path components (prevents ../../etc/passwd style names
// from being stored in DB and returned to browsers).
filename = filepath.Base(filename)
if len(filename) > 255 {
filename = filename[:255]
}
if filename == "" || filename == "." {
http.Error(w, "bad request: invalid filename", http.StatusBadRequest)
return
}
fileUUID := uuid.New()
s3Key := "files/" + tablo.ID.String() + "/" + fileUUID.String() // D-04
contentType, bytesWritten, err := deps.Files.Upload(r.Context(), s3Key, file)
if err != nil {
slog.Default().Error("files upload: Upload failed", "tablo_id", tablo.ID, "err", err)
http.Error(w, "internal server error", http.StatusInternalServerError)
return
}
_, err = deps.Queries.InsertTabloFile(r.Context(), sqlc.InsertTabloFileParams{
TabloID: tablo.ID,
S3Key: s3Key,
Filename: filename,
ContentType: contentType,
SizeBytes: bytesWritten,
})
if err != nil {
slog.Default().Error("files upload: InsertTabloFile failed", "tablo_id", tablo.ID, "s3_key", s3Key, "err", err)
// Best-effort S3 cleanup — orphan prevention until Phase 6 reconciler exists.
cleanupCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
if delErr := deps.Files.Delete(cleanupCtx, s3Key); delErr != nil {
slog.Default().Error("files upload: S3 cleanup after DB failure", "s3_key", s3Key, "err", delErr)
}
cancel() // call immediately after Delete, not via defer
http.Error(w, "internal server error", http.StatusInternalServerError)
return
}
updatedFiles, err := deps.Queries.ListFilesByTablo(r.Context(), tablo.ID)
if err != nil {
slog.Default().Error("files upload: ListFilesByTablo failed", "tablo_id", tablo.ID, "err", err)
updatedFiles = []sqlc.TabloFile{}
}
if updatedFiles == nil {
updatedFiles = []sqlc.TabloFile{}
}
if r.Header.Get("HX-Request") == "true" {
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.Header().Set("HX-Retarget", "#tab-content")
w.Header().Set("HX-Reswap", "innerHTML")
_ = templates.FilesTabFragment(tablo, updatedFiles, csrf.Token(r)).Render(r.Context(), w)
return
}
http.Redirect(w, r, "/tablos/"+tablo.ID.String()+"/files", http.StatusSeeOther)
}
}
// FileDownloadHandler handles GET /tablos/{id}/files/{file_id}/download.
// Generates a 5-minute presigned URL and returns a 302 redirect to it (FILE-04).
//
// Security invariants:
// - deps.Files nil guard is the FIRST statement (T-05-03-06)
// - Ownership enforced by loadOwnedTabloForFile (T-05-03-02, FILE-06)
// - Presigned URL has 5-minute TTL set inside files.Store.PresignDownload (T-05-03-01)
func FileDownloadHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if deps.Files == nil {
http.Error(w, "storage not configured", http.StatusServiceUnavailable)
return
}
tablo, file, _, ok := loadOwnedTabloForFile(w, r, deps)
if !ok {
return
}
_ = tablo
url, err := deps.Files.PresignDownload(r.Context(), file.S3Key)
if err != nil {
slog.Default().Error("files download: PresignDownload failed", "file_id", file.ID, "err", err)
http.Error(w, "internal server error", http.StatusInternalServerError)
return
}
http.Redirect(w, r, url, http.StatusFound)
}
}
// FileDeleteConfirmHandler handles GET /tablos/{id}/files/{file_id}/delete-confirm.
// Renders an inline deletion confirmation fragment (same HTMX pattern as task delete).
//
// Security invariants:
// - deps.Files nil guard is the FIRST statement (T-05-03-06)
// - Ownership enforced by loadOwnedTabloForFile (T-05-03-02, FILE-06)
func FileDeleteConfirmHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if deps.Files == nil {
http.Error(w, "storage not configured", http.StatusServiceUnavailable)
return
}
tablo, file, _, ok := loadOwnedTabloForFile(w, r, deps)
if !ok {
return
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
_ = templates.FileDeleteConfirmFragment(tablo.ID, file, csrf.Token(r)).Render(r.Context(), w)
}
}
// FileDeleteHandler handles POST /tablos/{id}/files/{file_id}/delete.
// Deletes S3 object first (logs failure but continues), then removes DB row (FILE-05).
//
// Security invariants:
// - deps.Files nil guard is the FIRST statement (T-05-03-06)
// - Ownership enforced by loadOwnedTabloForFile (T-05-03-03, FILE-06)
// - CSRF enforced by gorilla/csrf middleware on the router (T-05-03-05)
// - S3 failure is logged but does NOT abort DB delete — orphan objects are Phase 6 worker concern (T-05-03-04)
func FileDeleteHandler(deps FilesDeps) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if deps.Files == nil {
http.Error(w, "storage not configured", http.StatusServiceUnavailable)
return
}
tablo, file, _, ok := loadOwnedTabloForFile(w, r, deps)
if !ok {
return
}
// Step 1: Delete from S3. Log failure but always continue to DB delete.
if err := deps.Files.Delete(r.Context(), file.S3Key); err != nil {
slog.Default().Error("files delete: S3 Delete failed", "key", file.S3Key, "err", err)
// Do NOT return — orphan S3 objects are reconciled by Phase 6 worker.
}
// Step 2: Delete DB row. This is the authoritative state.
if err := deps.Queries.DeleteTabloFile(r.Context(), sqlc.DeleteTabloFileParams{
ID: file.ID,
TabloID: tablo.ID,
}); err != nil {
slog.Default().Error("files delete: DeleteTabloFile failed", "id", file.ID, "err", err)
http.Error(w, "internal server error", http.StatusInternalServerError)
return
}
if r.Header.Get("HX-Request") == "true" {
w.Header().Set("Content-Type", "text/html; charset=utf-8")
_ = templates.FileRowGone(file.ID).Render(r.Context(), w)
return
}
http.Redirect(w, r, "/tablos/"+tablo.ID.String()+"/files", http.StatusSeeOther)
}
}