From the server side, fileEntry tries to push updates after every 2 seconds, and only if the client has not fallen far behind in receiving the pushes, or else it freezes after the upload has completed, trying to catch-up on the queued push notifications.

Right now I'm observing a behaviour where only the 100% progress is being shown, and possibly an early 1% progress, and maybe another sporadic update, on uploads that take 50+ seconds, for large files.


Here's the raw log:

tryPush() percent: 1
updateResourceContents() contents: {"percent":1,"results":["example-form:file-entry"]}
deltaGottenPushed: 2 lastDeltaGottenPushed: 0
tryPush() Pushed progress update
ProgressResource.getInputStream() progressInfo: {"percent":1,"results":["example-form:file-entry"]}
ProgressResource.getInputStream() progressInfo: {"percent":1,"results":["example-form:file-entry"]}
tryPush() percent: 29
updateResourceContents() contents: {"percent":29,"results":["example-form:file-entry"]}
deltaGottenPushed: 1 lastDeltaGottenPushed: 0
tryPush() Pushed progress update
tryPush() percent: 51
updateResourceContents() contents: {"percent":51,"results":["example-form:file-entry"]}
deltaGottenPushed: 2 lastDeltaGottenPushed: 0
tryPush() Pushed progress update
tryPush() percent: 66
updateResourceContents() contents: {"percent":66,"results":["example-form:file-entry"]}
deltaGottenPushed: 3 lastDeltaGottenPushed: 0
tryPush() percent: 79
updateResourceContents() contents: {"percent":79,"results":["example-form:file-entry"]}
deltaGottenPushed: 4 lastDeltaGottenPushed: 3
tryPush() Pushed progress update
tryPush() percent: 98
updateResourceContents() contents: {"percent":98,"results":["example-form:file-entry"]}
deltaGottenPushed: 5 lastDeltaGottenPushed: 3
ProgressResource.getInputStream() progressInfo: {"percent":98,"results":["example-form:file-entry"]}
ProgressResource.getInputStream() progressInfo: {"percent":98,"results":["example-form:file-entry"]}
tryPush() percent: 100
updateResourceContents() contents: {"percent":100,"results":["example-form:file-entry"]}
deltaGottenPushed: 4 lastDeltaGottenPushed: 5
tryPush() Pushed progress update
ProgressResource.getInputStream() progressInfo: {"percent":100,"results":["example-form:file-entry"]}
ProgressResource.getInputStream() progressInfo: {"percent":100,"results":["example-form:file-entry"]}
ProgressResource.getInputStream() progressInfo: {"percent":100,"results":["example-form:file-entry"]}
ProgressResource.getInputStream() progressInfo: {"percent":100,"results":["example-form:file-entry"]}


What that actually meant was that:

2 second rate limited code path at 1%
- Updated progress resource to contain 1%
- The progress resource reads aren't too far behind the pushes, so do a push of 1%

Progress resource being read twice in rapid succession, possibly framework itself causing double access for single GET. For 1%

2 second rate limited code path at 29%
- Updated progress resource to contain 29%
- The progress resource reads aren't too far behind the pushes, so do a push of 29%

2 second rate limited code path at 51%
- Updated progress resource to contain 51%
- The progress resource reads aren't too far behind the pushes, so do a push of 51%

2 second rate limited code path at 66%
- Updated progress resource to contain 66%
- The progress resource reads have fallen behind the pushes, so do not do a push of 66%

2 second rate limited code path at 79%
- Updated progress resource to contain 79%
- The progress resource reads have fallen behind the pushes, so do not do a push of 79%

2 second rate limited code path at 98%
- Updated progress resource to contain 98%
- The progress resource reads have fallen behind the pushes, so do not do a push of 98%

Progress resource being read twice in rapid succession, possibly framework itself causing double access for single GET. For 98%

Final update code path at 100%
- Updated progress resource to contain 100%
- Force a push of 100%

Progress resource being read twice in rapid succession, possibly framework itself causing double access for single GET. For 100%

Progress resource being read twice in rapid succession, possibly framework itself causing double access for single GET. For 100%


So, we did a total of 4 pushes and there were 4 reads. The rate limiting worked, where we didn't flood the pushes too frequently, and adapt to the browser not reading frequently. But, the problem we do have, is that the browser is not reading the progress resource soon enough. The browser should be able to read the progress resource more than 4x in almost a minute. It's not clear to me if the server is taking too long to notify the browser of a push, or if the browser is taking too long to respond to a push that it has received. Or both.