switch the notebook's templating system to Jinja2

[dandrake]

We should switch the notebook's templating system from Jinja to Jinja2. Jinja2, among other things, makes i18n much easier.

CC: @mwhansen @qed777 @dandrake

Component: notebook

Author: Tim Dumol, Dan Drake

Reviewer: Mitesh Patel

Merged: sagenb-0.7

Issue created by migration from https://trac.sagemath.org/ticket/7249

[dandrake]

apply to sagenb repo

[dandrake]

comment:1

Attachment: trac_7249_switch_notebook_to_jinja2.patch.gz

[dandrake]

Author: Dan Drake

[qed777]

comment:2

#7269 should now include these changes.

[TimDumol]

comment:3

#7269 no longer includes these changes. Refer to #7269 comment:25.

Changes must be made to deal with unicode encoding/decoding before this can be reviewed.

[dandrake]

comment:4

Replying to @TimDumol:

#7269 no longer includes these changes. Refer to #7269 comment:25.

Changes must be made to deal with unicode encoding/decoding before this can be reviewed.

At #7269 comment:24 you say that we need Model-View-Presenter/Controller separation. How hard will that be? It sounds hard. :) I've run into Unicode string problems while trying to internationalize the notebook, so I'd definitely like to do this if it's the right way to go about it.

[TimDumol]

comment:5

MVC [1] separates the layers of the program into a model, which has the data; views, which are ways to present the data; and the controller/s, which control which data to show etc.

Currently the notebook serves as a model/controller and has some view functions mixed into it (html_*). Separating things will make things cleaner, and will make dealing with unicode easier: the view is presented with encoded byte strings, the controller deals with unicode strings, and data is retrieved from the model (db or filesystem) in encoded data which is converted to unicode strings.

Without this separation, one will need to check whether each string passed is an encoded byte string or a unicode string.

Separation will entail first removing the html_* functions, which in turn means restructuring the templates. I'll be working on that very soon.

[1] http://en.wikipedia.org/wiki/Model%E2%80%93view%E2%80%93controller