When autoscroll was disabled, terminal could run on endlessly, eating
memory until the browser crashes. Now a hard upper limit ensures
that not more than 3000 lines are ever stored in the terminal. If autoscroll
is disabled and the limit is reached, no more log lines will be added. That
ensures that the log will not scroll and the current log excerpt will stay put.
UI + assets should actually have ETag and LastModified headers and proper
IfMatch handling on the server side and hence the server should do the
right thing on its own.
That should improve performance tremendously.
Both ETag and LastModified depend on all files the template rendering
depends on. If any of the depended on files changes, both values will
change as well. That allows us to track whether our cached copy is
still current (and force a refresh if not) and also process IfMatch request
headers and reply with a 304 directly so that we do not even have to
transfer the data if nothing changed and the browser still has it.
Also now tracks timestamps of last access to a preemptively cached
resource and cleans up stuff that hasn't been accessed in a while (7 days
by default)
Introduced a @preemptively_cached decorator that for decorated views
persists the provided data in ~/.octoprint/data/preemptive_flask_cache.yaml
in a list indexed by the view's path if the data is not yet part of the list.
During initialization the server will iterate over the persisted paths and data
and for each persisted path and entry in the list initialize a temporary WSGI
environment based on the data (which is interpretated as keyword arguments
to werkzeug's EnvironmentBuilder) which will then be used to call the view
function in the correct context.
The current implementation for / and /i18n/<locale>/messages.js utilizes
that decorator to allow preemptive caching of those views (/ being probably
the most expensive one in the whole core application) utilizing request base URLs
(internal access, external access, reverse proxy with prefix url etc) that had been
encountered in the past.
Through the new config setting server.preemptiveCaching.exceptions it is
possible to define a set of base URLs to never cache. Preemptive caching can
be globally disabled by setting devel.cache.preemptive to false.
This way we create separate caches for URLs access via different schemes/prefixes/etc.
Otherwise our generated page might not work when accessing OctoPrint from external
after accessing it from internal once.
Otherwise the GCODE Viewer will get stuck "half way through" if
"sync with progress" is enabled but the tab/browser tab loses focus
during printing and only regains it after the print has finished.
This might help with #1065 if indeed is related to background tab suspending behaviours in
browsers, but is a completely blind guess at this point since I still have not been able to
reproduce that issue myself.
Backported.
(cherry picked from commit 720cdad)
While at it also adjusted highlighting so that the folder containing
the currently selected file will be highlighted if the selected file is
not within the current folder but in one of its sub folders.
This might help with #1065 if indeed is related to background tab suspending behaviours in
browsers, but is a completely blind guess at this point since I still have not been able to
reproduce that issue myself.
Having the plugin commands on the first level of --help proved to be
a bad idea since it basically kills every chance of lazy loading the (expensive)
plugin context. Using a sub command for anything plugin related allows us
to only fire up the plugin context if a plugin command is expected, saving us
some precious seconds of operation in all other cases.
For conformity reasons the dev sub commands were now restructured
similarly.
We don't actually need the pip caller, which necessitates version
detection and hence increases waiting times tremendously - a simple
command line call with the auto detected pip command for
uninstalling stuff is enough and cuts off a lot of the CLI response times.
If the python version is < 2.7.9, we try to patch urllib3 with pyopenssl
to get rid of any InsecurePlatform issues.
That only works if pyopenssl plus dependencies are installed however,
hence we also log that.
Now that the plugin manager gets initialized before the server gets even constructed, we need
to log that entry right after we've set up logging in order to post any plugin manager related
log entries after.
