recover from file access errors when zipping

copyparty/star.py

@@ -1,6 +1,8 @@
+import os
 import tarfile
 import threading
 
+from .sutil import errdesc
 from .util import Queue, fsenc
 
 
@@ -22,6 +24,7 @@ class StreamTar(object):
         self.co = 0
         self.qfile = QFile()
         self.fgen = fgen
+        self.errf = None
 
         # python 3.8 changed to PAX_FORMAT as default,
         # waste of space and don't care about the new features
@@ -42,9 +45,10 @@ class StreamTar(object):
             yield buf
 
         yield None
+        if self.errf:
+            os.unlink(self.errf["ap"])
 
-    def _gen(self):
+    def ser(self, f):
-        for f in self.fgen:
         name = f["vp"]
         src = f["ap"]
         fsi = f["st"]
@@ -60,5 +64,21 @@ class StreamTar(object):
         with open(fsenc(src), "rb", 512 * 1024) as f:
             self.tar.addfile(inf, f)
 
+    def _gen(self):
+        errors = []
+        for f in self.fgen:
+            if "err" in f:
+                errors.append([f["vp"], f["err"]])
+                continue
+
+            try:
+                self.ser(f)
+            except Exception as ex:
+                errors.append([f["vp"], repr(ex)])
+
+        if errors:
+            self.errf = errdesc(errors)
+            self.ser(self.errf)
+
         self.tar.close()
         self.qfile.q.put(None)

copyparty/sutil.py

@@ -0,0 +1,21 @@
+import os
+import time
+import tempfile
+
+
+def errdesc(errors):
+    report = ["copyparty failed to add the following files to the archive:", ""]
+
+    for fn, err in errors:
+        report.extend([" file: {}".format(fn), "error: {}".format(err), ""])
+
+    with tempfile.NamedTemporaryFile(prefix="copyparty-", delete=False) as tf:
+        tf_path = tf.name
+        tf.write("\r\n".join(report).encode("utf-8", "replace"))
+
+    os.chmod(tf_path, 0o444)
+    return {
+        "vp": "archive-errors-{}.txt".format(int(time.time())),
+        "ap": tf_path,
+        "st": os.stat(tf_path),
+    }

copyparty/szip.py

@@ -1,8 +1,10 @@
+import os
 import time
 import zlib
 import struct
 from datetime import datetime
 
+from .sutil import errdesc
 from .util import yieldfile, sanitize_fn
 
 
@@ -187,8 +189,7 @@ class StreamZip(object):
         self.pos += len(buf)
         return buf
 
-    def gen(self):
+    def ser(self, f):
-        for f in self.fgen:
         name = f["vp"]
         src = f["ap"]
         st = f["st"]
@@ -225,6 +226,25 @@ class StreamZip(object):
             buf = gen_fdesc(sz, crc, z64)
             yield self._ct(buf)
 
+    def gen(self):
+        errors = []
+        for f in self.fgen:
+            if "err" in f:
+                errors.append([f["vp"], f["err"]])
+                continue
+
+            try:
+                for x in self.ser(f):
+                    yield x
+            except Exception as ex:
+                errors.append([f["vp"], repr(ex)])
+
+        if errors:
+            errf = errdesc(errors)
+            print(repr(errf))
+            for x in self.ser(errf):
+                yield x
+
         cdir_pos = self.pos
         for name, sz, ts, crc, h_pos in self.items:
             buf = gen_hdr(h_pos, name, sz, ts, self.utf8, crc, self.pre_crc)
@@ -242,3 +262,6 @@ class StreamZip(object):
 
         ecdr, _ = gen_ecdr(self.items, cdir_pos, cdir_end)
         yield self._ct(ecdr)
+
+        if errors:
+            os.unlink(errf["ap"])