I have installed the less-rails gem as I am keen to use the colour manipulation LESS offers. I need to extract a colour from my database as my themes base colour, and build up from there.
I have the static CSS, and have renamed it styles.css.less to ensure that rails understands the less extension, which it appears to.
The next thing I tried was to also wrap the file as an erb, to hopefully allow ruby string literals to process before being sent to LESS, and eventually outputting as valid CSS (still with me?)
The file is now called style.css.less.erb. While the file simple contains valid CSS, the processing of the document works. As soon as I add a ruby string literal, it fails.
color: #{"#112233"};
In the chrome debugger, nothing after this line is getting processed.
What am I doing wrong, and how should I do what I am trying to do?
As Chowlett says in comments, you should use erb syntax: <%= "#112233" %>
Next step is get that value from db. If this color value is application-wide, probably you are looking for settings in db solution. I use rails-settings-cached gem for that. Your result code will looks like
color: <%= Setting.foo_color %>
If you are using assets on production, don't forget to recompile them after each setting change.
And if it's not a setting but probably something specific to each user then you can't use application-wide css files for that, but you can write inline css in views.
Related
By using Kristin Gem, Is there any possible way to store the result of the conversion on a variable instead of outputting it as a file?
Assuming that the link below goes to the gem you are talking about, no. The gem is a very thin layer on top of pdf2htmlEX and simply spawns the process with the arguments passed. Further, pdf2htmlEX doesn't seem to support redirecting its output and adding this feature doesn't seem to be on their todo list, so adding this functionality would require wrapping a different converter.
I think your best bet would be to save load the HTML to a variable after creation.
Kristin:https://github.com/ricn/kristin
Thread about adding output redirection to pdf2htmlEX: https://github.com/coolwanglu/pdf2htmlEX/issues/638
rails 3.2
I am new to slim, and I have to work with an application that's using it. Reading through some documentation, I see that using something like:
.class
which translates to:
<div class="class"></div>
In the code I inherited, in the .html.slim file, I have:
.form-section.customer_info
When I look through the stylesheets folder, I cannot find customer_info, but I can find form-section.
Shouldn't I be able to find customer_info in one of the stylesheets?
The answer is maybe you can find it in a stylesheet. But there are other cases, where you may not:
Sometimes a class is used as a target for a JavaScript snippet; if you find it mentioned in the javascript for the app, then you likely want to keep it because an interaction may depend on it (read the JS code to determine this).
Sometimes, the class has been removed from the stylesheet and not removed from the code; in this case you may remove it.
However, sometimes a class is added to mark the section of HTML as semantically significant so that styling can be applied to it at a future time; in that case, you may choose to keep it.
For instance, for better or ill, when I am writing code, I will name sections using classes, as .user-list or .part-table to indicate that, as the coder, I know the HTML code is going to contain users or parts. By doing this consistently I can mark out portions of the front end for later consistent styling by usage; that is, all the part tables can be styled the same way, all the user lists can be styled the same way, etc. Again, this is a convention I have seen used and that I practice. Nonetheless, these represent a few reasons why a class may be present in the HTML, but not referenced elsewhere.
I have situation where I generate stylesheets based on information in the database. This means I have a views/users/show.css.erb which contains code like:
a {
color: <%= #user.favorite_color %>;
}
Fair enough, works perfectly with a respond_to { |f| f.css } in my controller. However now I would like to use some of SASS's sassy functions like lighten, darken etc. in my CSS, so I would like to have SASS parse my view. However I cannot figure out how to register SASS as a template handler in my views without too much ugly hacks. I just don't get how it works. Has anyone ever tried this?
I have tried including SASS's Functions module but to no avail.
I was planning of doing the same for dynamic user themes some time ago. Back then, I found a mailing list answer to a similar question to yours, by Nathan Weizenbaum (author of SASS) which got me back on the straight and narrow:
On Mar 18, 11:46 am, Nathan Weizenbaum wrote:
There's a reason Sass doesn't allow dynamic access to Rails code - see
the Sass section ofhttp://haml.hamptoncatlin.com/docs/rdoc/files/FAQ.htmlfor
a brief discussion. Sass is also fairly slow, since it's only compiled once,
so this is probably far too slow for a production environment.
The link is not working anymore, but the SASS FAQ has only one section called Can I use a variable from my controller in my Sass file? which answer the dynamic question:
If you really, really need to compile Sass on each request, first make sure you have adequate caching set up. Then you can use Sass::Engine to render the code, using the :custom option to pass in data that can be accessed from your Sass functions.
So in general, SASS is not designed for dynamic css generation on each request. Rather it is intended to be used as a pre compilation solution to generate static css files.
When doing J2EE development, I find it handy for debugging to view the Java classes that are generated by the JSP compiler.
How can I do the equivalent in Ruby? Since it is all in memory, it won't generate a file that I can view. I believe it's the ERB module that generates the corresponding object for a template, so how can I actually view the object? Can I drop a debugger statement somewhere and use rdb? Is there some configuration value I can tell it to dump the object definition? I'm using rails, in case that makes a difference.
I don't think rails generates a class for your view. It basically calls eval after processing the file. Or do you mean inspecting the erb object while it's parsing your template?
If it's the latter you can find erb.rb in lib\ruby\1.9.1 I'd imagine you could just drop a debugger statement throughout that file.
I always make a habit of adding the following to my views (layout) which allows me to inspect or debug the parameters being used by the view in question.
<%= debug(params) %>
This will format all the parameters in yaml and display them in a Hash format.
Have a look at the method in the source code to get a better understanding. SOURCE
There are some differences compared with the Java way due to language differences.
Most template libraries for Ruby follow these steps when compiling/optimizing:
The template is compiled into Ruby source code -- not a class but a long procedure that appends to a string buffer while traversing the logic of the original template.
This ruby code is evaluated in order to be bound for later reference, preferably within a method body. This way, it is only parsed once by the interpreter.
The method (or other context) containing the logic of the parsed template is invoked to render it.
Anyway, the compiled template code therefore looks a lot like a much noisier version of your original template, and will generally not help you debugging, unless you're debugging the template language itself.
Anyone interested in template language implementation might enjoy a look around the Tilt code (use different template languages with the same rendering interface and optimization), and Temple (a great template language meta-implementation).
When I'm in an html.erb file, I get no snipMate snippets.
I would like both HTML and Ruby, or just HTML would be fine,
How would I do this?
Would I need to write a set of snippets?
If so, is there a way of pulling in existing snippets without copying them?
Is there a way of telling vim to go into html mode when it sees .html erb?
You can use an autocmd to set the filetype to html when opening a ".html.erb" file. This could have unwanted side effects for plugins that work for ".erb" files.
autocmd BufNewFile,BufRead *.html.erb set filetype=html
You can also load more than one set of snippets by using a dotted filetype:
autocmd BufNewFile,BufRead *.html.erb set filetype=html.eruby
See :help snippet-syntax in the snipMate help for more info.
Snippets are stored in directory called snippets somewhere in your ~/.vim folder.
If you look there, there is usually one file per filetype, there is a c.snippets, a ruby.snippets, so it seems what you have to do is to create an erb.snippets there with what you want.
Eventually you could copy the content of ruby.snippets and html.snippets into your new erb.snippets.
Alternatively you can search on github, some people have posted their own erb.snippets configuration. For example, there is a nice collection there :
https://github.com/scrooloose/snipmate-snippets
The best thing would to try first to open a snippet file and look at the syntax, it is pretty easy to create your own snippet depending on what you use the most.
I am currently on a promoting tour for UltiSnips on StackOverflow. UltiSnips supports extending other file types, your erb.snippets would look like this:
extends html, ruby, rails
snippet temp "A snippet only in Erb"
erb rules ${1}
endsnippet
A conversion script for snipMate snippets is shipped with UltiSnips, so switching is easy.
I used the autocommand method to the set the filetype, but then I got html syntax errors for things like this:
<%= image_tag("logo.png", :alt => "Sample App", :class => "round") %>
The last two angle brackets would be highlighted in red, which drove me bonkers. So, I created a symlink called eruby.snippets that points to html.snippets. That worked like a champ and now I don't have to make changes in two places. I also have an eruby-rails snippet directory for non-html eruby snippets.
This is on a Mac OS X system. Note that an alias won't work. You need to hit the terminal and use the ln command. Not sure about doing this on a Windoze system.
You can assign multiple snippets scopes to a single filetype. (I've found that altering the filetype tends to break some syntax highlighting).
You can check that the filetype for erb files is indeed 'eruby' with:
:set filetype?
If you're using the maintained fork of snipmate, it looks like you'll want both the eruby.snippets and eruby-rails.snippets from the snipmate-snippets repository (owned by honza, but I don't have enough reputation to link to it here) (see the INSTALL section of the snipmate README for proper setup).
If you are using the maintained fork, I believe setting g:snipMate.scope_aliases in your .vimrc with the following will work for your example:
let g:snipMate = {}
let g:snipMate.scope_aliases = {}
let g:snipMate.scope_aliases['eruby'] = 'eruby,eruby-rails'
I've added a pull request to snipmate to have their documentation updated.
Jumping on the UltiSnips bandwagon after trying SnipMate for a while. Like SirVer mentioned, having the html, ruby, etc snippets available within an *.erb file was as simple as adding the extend line to the eruby.snippets file.
With the original snipMate plugin, create a file ~/.vim/ftplugin/erb_snippets.vim and put the following into it:
silent call ExtractSnipsFile(g:snippets_dir . 'html.snippets', &l:filetype)
silent call ExtractSnipsFile(g:snippets_dir . 'ruby.snippets', &l:filetype)