Sablon
Is a document template processor for Word docx files. It leverages Word's
built-in formatting and layouting capabilities to make template creation easy
and efficient.
Note: Sablon is still in early development. Please report if you encounter any issues along the way.
Installation
Add this line to your application's Gemfile:
gem 'sablon'
Usage
require "sablon"
template = Sablon.template(File.("~/Desktop/template.docx"))
context = {
title: "Fabulous Document",
technologies: ["Ruby", "HTML", "ODF"]
}
template.render_to_file File.("~/Desktop/output.docx"), context
Writing Templates
Sablon templates are normal Word documents (.docx) sprinkled with MailMerge fields
to perform operations. The following section uses the notation «=title» to
refer to Word MailMerge fields.
A detailed description about how to create a template can be found here
Content Insertion
The most basic operation is to insert content. The contents of a context variable can be inserted using a field like:
«=title»
It's also possible to call a method on a context object using:
«=post.title»
NOTE: The dot operator can also be used to perform a hash lookup. This means that it's not possible to call methods on a hash instance. Sablon will always try to make a lookup instead.
This works for chained method calls and nested hash lookup as well:
«=buyer.address.street»
WordProcessingML
Generally Sablon tries to reuse the formatting defined in the template. However, there are situations where more fine grained control is needed. Imagine you need to insert a body of text containing different formats. If you can't decide the format ahead of processing time (in the template) you can insert WordProcessingML directly.
It's enough to use a simply insertion operation in the template:
«=long_description»
To insert WordProcessingML prepare the context accordingly:
word_processing_ml = <<-XML.gsub("\n", "")
<w:p>
<w:r w:rsidRPr="00B97C39">
<w:rPr>
<w:b />
</w:rPr>
<w:t>this is bold text</w:t>
</w:r>
</w:p>
XML
context = {
long_description: Sablon.content(:word_ml, word_processing_ml)
}
template.render_to_file File.("~/Desktop/output.docx"), context
IMPORTANT: This feature is very much experimental. Currently, the insertion will replace the containing paragraph. This means that other content in the same paragraph is discarded.
HTML [experimental]
Similar to WordProcessingML it's possible to use html as input while processing the tempalte. You don't need to modify your templates, a simple insertion operation is sufficient:
«=article.body»
To use HTML insertion prepare the context like so:
html_body = <<-HTML
<div>This text can contain <em>additional formatting</em>
according to the <strong>HTML</strong> specification.</div>
HTML
context = {
article: { html_body: Sablon.content(:html, html_body) }
}
template.render_to_file File.("~/Desktop/output.docx"), context
Currently HTML insertion is very limited and strongly focused on the HTML generated by Trix editor.
IMPORTANT: This feature is very much experimental. Currently, the insertion will replace the containing paragraph. This means that other content in the same paragraph is discarded.
Conditionals
Sablon can render parts of the template conditonally based on the value of a context variable. Conditional fields are inserted around the content.
«technologies:if»
... arbitrary document markup ...
«technologies:endIf»
This will render the enclosed markup only if the expression is truthy.
Note that nil, false and [] are considered falsy. Everything else is
truthy.
For more complex conditionals you can use a predicate like so:
«body:if(present?)»
... arbitrary document markup ...
«body:endIf»
Loops
Loops repeat parts of the document.
«technologies:each(technology)»
... arbitrary document markup ...
... use `technology` to refer to the current item ...
«technologies:endEach»
Loops can be used to repeat table rows or list enumerations. The fields need to be placed in within table cells or enumeration items enclosing the rows or items to repeat. Have a look at the example template for more details.
Nesting
It is possible to nest loops and conditionals.
Comments
Sometimes it's necessary to include markup in the template that should not be visible in the rendered output. For example when defining sample numbering styles for HTML insertion.
«comment»
... arbitrary document markup ...
«endComment»
Executable
The sablon executable can be used to process templates on the command-line.
The usage is as follows:
cat <context path>.json | sablon <template path> <output path>
If no <output path> is given, the document will be printed to stdout.
Have a look at this test for examples.
Examples
Using a Ruby script
There is a sample template in the repository, which illustrates the functionality of sablon:
Processing this template with some sample data yields the following output document. For more details, check out this test case.
Using the sablon executable
The executable test showcases the sablon
executable.
The template
is rendered using a json context to provide the data. Following is the resulting output:
Contributing
- Fork it ( https://github.com/senny/sablon/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create a new Pull Request
Inspiration
These projects address a similar goal and inspired the work on Sablon: