Do not allow OPTIONS request against / from Windows Explorer

[MorrisJobke]

• fixes HTTPS-WebDAV mount on Windows failes if NC is installed to webserver-root #2979

cc @michag86

• add integration tests

[mention-bot]

@MorrisJobke, thanks for your PR! By analyzing the history of the files in this pull request, we identified @LukasReschke, @bartv2 and @icewind1991 to be potential reviewers.

[michag86]

User agents used by windows webdav client:

windows 7 - webclient is not running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:27:36 +0100] "OPTIONS / HTTP/1.1" 302 309 "-" "DavClnt"
windows 7 - webclient is running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:27:43 +0100] "OPTIONS / HTTP/1.1" 302 3287 "-" "Microsoft-WebDAV-MiniRedir/6.1.7601"

windows 8.1 - webclient is not running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:09:54 +0100] "OPTIONS / HTTP/1.1" 302 4433 "-" "DavClnt"
windows 8.1 - webclient is running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:09:57 +0100] "OPTIONS / HTTP/1.1" 302 4433 "-" "Microsoft-WebDAV-MiniRedir/6.3.9600"

windows 10 - webclient is not running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:15:58 +0100] "OPTIONS / HTTP/1.1" 302 4433 "-" "DavClnt"
windows 10 - webclient is running
aaa.bbb.ccc.ddd - - [09/Jan/2017:14:16:02 +0100] "OPTIONS / HTTP/1.1" 302 4433 "-" "Microsoft-WebDAV-MiniRedir/10.0.14393"

Because we need to get the WebClient running, it's only needed to check for agend "DavClnt".

[MorrisJobke]

Because we need to get the WebClient running, it's only needed to check for agend "DavClnt".

Done :)

[michag86]

Changes tested on NC 10.0.1 👍

[codecov-io]

Current coverage is 54.13% (diff: 0.00%)

Merging #2986 into master will increase coverage by 0.01%

@@             master      #2986   diff @@
==========================================
  Files          1304       1304          
  Lines         80561      80597    +36   
  Methods        7961       7965     +4   
  Messages          0          0          
  Branches       1245       1245          
==========================================
+ Hits          43598      43628    +30   
- Misses        36963      36969     +6   
  Partials          0          0          

Diff Coverage	File Path
0%	lib/base.php

Powered by Codecov. Last update fee18d6...e26533d

[Flole998]

This code is violating the HTTP Code specifications. You're returning 200 on an empty result, that is discouraged in favor of using code 204. Anyways, I propose to use a redirect in htaccess as dav is an app and no app code should be included in the base installation. In htaccess also other webdav stuff is handled. See #3370

[MorrisJobke]

You are right. And it's also a major hack. Let's go for the cleaner redirect.