KeyError: 'piece_size' in fileNeed command in BigfilePlugin when try to download non-optional files with |all

[krzotr]

Step 1: Please describe your environment

• ZeroNet version: 0.7.0 4197
• Operating system: Fedora 30 x64
• Web browser: Chromium 75.0.3770.100
• Tor status: not available
• Opened port: yes

Step 2: Describe the problem:

I try to use fileNeed command with |all to download data/mp4-redditgifs/9450.mp4 file from address1Gif7PqWTzVWDQ42Mo7np3zXmGAo3DXc7h. I received error {"error": "KeyError: piece_size"}

Steps to reproduce:

I used fileNeed to try download file, the most important thing is |all at the end.

{"cmd":"fileNeed","params":"data/mp4-redditgifs/9450.mp4|all","wrapper_nonce":"6a0201394d5a983802bed79f159fc037a8a6693603d09a6e227e65c64a170f8a","id":3}
{"cmd": "response", "to": 3, "result": {"error": "KeyError: piece_size"}, "id": 7}

Observed Results:

As you can see in response I got "error": "KeyError: piece_size". I enabled traceback:

Traceback (most recent call last):#### Expected Results:
  File "/home/ko/dev/zeronet/src/Ui/UiWebsocket.py", line 704, in actionFileNeed
    self.site.needFile(inner_path, priority=6)
  File "/home/ko/dev/zeronet/plugins/Bigfile/BigfilePlugin.py", line 757, in needFile
    piece_size = file_info["piece_size"]
KeyError: 'piece_size'

The problem is in BigfilePlugin.py in needFile function.

File data/mp4-redditgifs/9450.mp4 is not marked as optional file and piece_size does not exist in content.json file, check 1Gif7PqWTzVWDQ42Mo7np3zXmGAo3DXc7h/content.json:

  "data/mp4-redditgifs/9450.mp4": {
   "sha512": "36134aa4525d5985b1440d42e2b33580df56a179b4b0c71d0234947008a4fc12",
   "size": 1042259
  },

Expected Results:

If file is not marked as optional should be downloaded correcty with |all at the end.

I created patch which fixed this problem. If piece_size index does not exist in file_info - just use default needFile function from SitePlugin