[repo] Add a publish/subscribe mechanism for inter-instance communication using zmq
Each repo can have a publishing and any number of subscribing sockets
whose addresses are specified in the instance's configuration. An
application or cube can subscribe to some 'topics', and give a callback
that gets called when a message matching that topic is received.
As a proof of concept, this introduces a hook to clean up the caches
associated with the repository when an entity is deleted.
A subscription is added using Repository::zmq::add_subscription;
the callback receives a list representing the received multi-part
message as argument (the first element of the message is its topic).
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Refactoring the CSSs with UI properties
=========================================
Overview
=========
Managing styles progressively became difficult in CubicWeb. The
introduction of uiprops is an attempt to fix this problem.
The goal is to make it possible to use variables in our CSSs.
These variables are defined or computed in the uiprops.py python file
and inserted in the CSS using the Python string interpolation syntax.
A quick example, put in ``uiprops.py``::
defaultBgColor = '#eee'
and in your css::
body { background-color: %(defaultBgColor)s; }
The good practices are:
- define a variable in uiprops to avoid repetitions in the CSS
(colors, borders, fonts, etc.)
- define a variable in uiprops when you need to compute values
(compute a color palette, etc.)
The algorithm implemented in CubicWeb is the following:
- read uiprops file while walk up the chain of cube dependencies: if
cube myblog depends on cube comment, the variables defined in myblog
will have precedence over the ones in comment
- replace the %(varname)s in all the CSSs of all the cubes
Keep in mind that the browser will then interpret the CSSs and apply
the standard cascading mechanism.
FAQ
====
- How do I keep the old style?
Put ``STYLESHEET = [data('cubicweb.old.css')]`` in your uiprops.py
file and think about something else.
- What are the changes in cubicweb.css?
Version 3.9.0 of cubicweb changed the following in the default html
markup and css:
=============== ==================================
old new
=============== ==================================
.navcol #navColumnLeft, #navColumnRight
#contentcol #contentColumn
.footer #footer
.logo #logo
.simpleMessage .loginMessage
.appMsg (styles are removed from css)
.searchMessage (styles are removed from css)
=============== ==================================
Introduction of the new cubicweb.reset.css based on Eric Meyer's
reset css.
Lots of margin, padding, etc.