empty topic tree when DO_NOT_RELOAD_CONTENT_CACHE_AT_STARTUP = True

[66eli77]

steps to reproduce:

1. delete the topics.json_en.cache file in your data/khan folder
2. set DO_NOT_RELOAD_CONTENT_CACHE_AT_STARTUP = True in local_settings.py or your way of assigning tags
3. start kalite server
4. go to learn page and you will see an empty sidebar

[radinamatic]

Since @66eli77 labeled this with bug bash I'm guessing he was experiencing it on 0.14. Just to confirm it's happening on develop too.

[benjaoming]

I'm seeing the same in alpha9.

[benjaoming]

Problem is this:

WARNING:kalite:Annotated exercise cache file failed in saving with error [Errno 13] Permission denied: '/usr/share/kalite/data/khan/exercises.json_en.cache'
INFO:kalite:Preloading content data for language en.
WARNING:kalite:Annotated content cache file failed in saving with error [Errno 13] Permission denied: '/usr/share/kalite/data/khan/contents.json_en.cache'
INFO:kalite:Preloading topic tree data for language en.
WARNING:kalite:Annotated topic cache file failed in saving with error [Errno 13] Permission denied: '/usr/share/kalite/data/khan/topics.json_en.cache'

These files cannot be in that location, they have to be treated as user data.

[benjaoming]

Okay I'm going to work on the issue about saving cache files in a system-location.

@rtibbles if there are other causes of this bug, feel free to work on them concurrently, otherwise I'll let you know if this resolves the issue...

[benjaoming]

Issue is resolved in the PR, I made a bunch of commit amendments, hence the odd list of commits above.

[MCGallaspy]

@66eli77 can you try to reproduce this now that #4122 has been merged into develop I mean 0.14.x?

[66eli77]

@MCGallaspy I git pull from 0.14.x, then make sure there is no topics.json_en.cache in my data/khan folder, then set DO_NOT_RELOAD_CONTENT_CACHE_AT_STARTUP = True in local_settings.py and start the server with ./bin/kalite start, when open the learn page, the sidebar is populated.

[benjaoming]

@66eli77 FYI the cache files have been moved, that was part of the fix: They now live in ~/.kalite/cache