Client shouldn't chunk in case no chunking capabilities were announced.

[TheOneRing]

#7849

See related owncloud/ocis#195

Whenever the capability "bigfilechunking" is set to false, the desktop client must not attempt to use the chunking v1 algorithm (this one

client/src/libsync/propagateuploadv1.cpp

Line 104 in f076682

headers[QByteArrayLiteral("OC-Chunked")] = QByteArrayLiteral("1");

)

the capability attribute is in:

"ocs": {
    "data": {
      ...
      "capabilities": {
        ...
        "files": {
          ...
          "bigfilechunking": false,
        },

I guess the check was never implemented in the desktop client as chunking v1 was always supported by OC from start. So now dealing with OCIS with no or broken support makes this check necessary.

---

Similar when OWNCLOUD_CHUNK_SIZE=0 was set

Also in case:
"bigfilechunking": false,

Related:
owncloud/ocis#203
owncloud/ocis#272

[jnweiger]

Chunking settings are in multiple places in the capabulities report:

curl -s -u admin:admin 'http://pigpen.jw-qa.owncloud.works/ocs/v1.php/cloud/capabilities?format=json'  | jq '.ocs.data.capabilities.dav,.ocs.data.capabilities.files'

.ocs.data.capabilities.dav: { "chunking": "1.0", ...
.ocs.data.capabilities.files: { "bigfilechunking": true, ...

These capabilities are normally hardcoded per server. There is no GUI or config file to tune them.
For testing purposes, edited /var/www/owncloud/apps/{dav,files}/lib/Capabilities.php -- Edit at own risk :-)

[jnweiger]

Tested with
testpilotcloud 2.7.0daily20201019 (build 2311) on Linux and 2.7.0rc1 on windows
against a 10.5.0 server:

curl -s -u admin:admin 'http://pigpen.jw-qa.owncloud.works/status.php'
{"installed":true,"maintenance":false,"needsDbUpgrade":false,"version":"10.5.0.10","versionstring":"10.5.0","edition":"Community","productname":"ownCloud"}

We disable all chunking support on the server side by editing apps/dav/lib/Capabilities.php and apps/files/lib/Capabilities.php so that the server does not announce any chunking capabilities:

curl -s -u admin:admin 'http://pigpen.jw-qa.owncloud.works/ocs/v1.php/cloud/capabilities?format=json'  | jq . | grep chunk
          "bigfilechunking": false,
          "chunking": "",

Steps to reproduce

• make sure, no CHUNKING environment variables are set: env | grep CHUNK reports nothing.
• connect client to server, with logging enabled
• wait for initial sync
• move a 42MB file into the desktop sync folder
• wait until upload finishes
• check the logfiles

zgrep -i nextchunk 20201028_1132_owncloud.log.0.gz 
10-28 11:32:18:534 [ debug sync.propagator.upload.v1 ]	[ OCC::PropagateUploadFileV1::startNextChunk ]:	5 false 0 10000000
10-28 11:32:18:535 [ debug sync.propagator.upload.v1 ]	[ OCC::PropagateUploadFileV1::startNextChunk ]:	5 false 10000000 10000000
10-28 11:32:18:535 [ debug sync.propagator.upload.v1 ]	[ OCC::PropagateUploadFileV1::startNextChunk ]:	5 false 20000000 10000000
10-28 11:33:34:715 [ debug sync.propagator.upload.v1 ]	[ OCC::PropagateUploadFileV1::startNextChunk ]:	5 false 30000000 10000000
10-28 11:34:20:953 [ debug sync.propagator.upload.v1 ]	[ OCC::PropagateUploadFileV1::startNextChunk ]:	5 true 40000000 3994768

The client did chunking.

Expected behaviour: no chunking.

[jnweiger]

Tried more combinations too:

• removed both 'chunking' and 'bigfilechunking' completely from the capabilities
• removed chunking, but preserve 'bigfilechunking=true' as old servers did
  Always same results. 10MB chunking kicks in.

20201028_1148_owncloud.log.0.gz
20201028_1147_owncloud.log.0.gz
20201028_1146_owncloud.log.2.gz
20201028_1146_owncloud.log.1.gz
20201028_1146_owncloud.log.0.gz
20201028_1144_owncloud.log.0.gz
20201028_1135_owncloud.log.0.gz
20201028_1134_owncloud.log.0.gz
20201028_1132_owncloud.log.0.gz

[jnweiger]

We need to restart the client, when changing the settings.
Changing server capabilities while the client is connected is unrealistic, given that these values are normally hardcoded per server.

Retesting the 42MB file upload with restarting the client before changing the server capabilities:

usecase	bigfilechunking	chunking	desktop client 2.7.0 rc1
oC 7.0 .. 9.1	true	undefined	"Chunking V1": exactly 10MB
	true	""	"Chunking V1": exactly 10MB
oC 10.0.2	true	"1.0"	"Chunking NG": upload of 10000000, 22019345, 11975423
	false	undefined	one big chunk: startNextChunk ]: 1 true 0 43994768 OC-Chunk-Size: 10000000, OC-Total-Length: 43994768,
ocis-beta5	false	""	one big chunk: startNextChunk ]: 1 true 0 43994768 OC-Chunk-Size: 10000000, OC-Total-Length: 43994768,
	false	"1.0"	one big chunk: startNextChunk ]: 1 true 0 43994768 OC-Chunk-Size: 10000000, OC-Total-Length: 43994768,

Usecases were not really tested with these server versions. Recorded here as seen in owncloud/product#39

[jnweiger]

Takeaway:

• We ignore the reported OC-Chunk-Size in the logs -- the actual upload is in one big chunk and is considered "no chunking".
• The capability `chunking="1.0" does not enable "Chunking V1" -- it switches to "NG" instead.