= Rails-LaTeX

* Git: https://github.com/baierjan/rails-latex
* Original author: Geoff Jacobsen
* Copyright: 2010-2015 Geoff Jacobsen, Jan Baier and contributors
* License: MIT-LICENSE

== Description

rails-latex is a renderer for rails, which allows tex files with erb to be turned into an inline pdf.

== Synopsis

app/helpers/application_helper.rb:
   def lesc(text)
     LatexToPdf.escape_latex(text)
   end

app/views/stories/show.html.erb:
   ...
   <%= link_to "print", story_path(@story,:format => :pdf) %>


app/views/stories/show.pdf.erb:
   ...
   <%= lesc @story.name % >

app/views/layouts/application.pdf.erbtex:
   \documentclass[12pt,a4paper,sloppy,< %= @landscape % >]{article}
   ...
   < %= yield % >
   \end{document}


config/initializers/mime_types.rb:
   ...
   Mime::Type.register "application/pdf", :pdf, ['text/pdf'], ['pdf']


Only the file containing the \\documentclass should be of type: .pdf.erbtex . Partials and views (when there is a layout)
should be of type .pdf.erb .

If a LaTeX package requires more than one parser run add the following to the .pdf.erbtex file:

   <% @latex_config={:parse_runs => 3} %>

You can override the defaults like so:

   LatexToPdf.config.merge! :command => 'xetex', :arguments => ['-etex'], :parse_runs => 2

or to change just the arguments:

   LatexToPdf.config[:arguments].delete('-halt-on-error')

The defaults are:
   command: 'pdflatex'
   arguments: ['-halt-on-error']
   parse_runs: 1

The last log file is moved to tmp/rails-latex/input.log , and the corresponding
source TeX file to tmp/rails-latex/input.tex . If the PDF is not produced the
build directory is not removed; an archive script should be written to
occasionally clean up the tmp/rails-latex directory.

See the rails application under examples/rails-latex-demo/ for a working example.

=== Generating a String

If you need to generate the LaTeX document as a string you can use the +render_to_string+ method. You will probably need
to pass the <tt>:layout => true</tt> option to invoke the PDF generator. Here is an example to generate an email attachment:

In the controller you will have something along the lines of:

   def send_email_method
     output = render_to_string(:template => "/your_model/your_view.pdf.erb", :layout => true)
     MyMailer.email_sender(current_user, output).deliver
   end

The thing to note is the :layout => true which is needed so that the pdf template can grab the application erbtex layout.
Then in your mailer:

   def email_sender(user, pdf_attachment)
     @user = user
     attachments["attachment_name.pdf"] = {:mime_type => 'application/pdf', :content => pdf_attachment}
     mail( .... )
   end

=== Exception handling and debugging

When LaTeX render fails, +RailsLatex::ProcessingError+ is thrown. In your code, you can catch it and react according to your
needs. To make your life easier, TeX source and log are attached to the exception as instance variables +src+ and +log+.

== Requirements

* ruby 1.8 or 1.9
* rails 3 or later

== Install

* gem install rails-latex

== Development

Developing rails-latex requires bundler and RedCloth

* rake test
* rake build

== Contributions

* Geoff Jacobsen
* Tommaso Patrizi
* Klaus Reske
* Jan Baier
* Jakub Cerny