Quick start

Create your first document in two steps: prepare a template, then write Ruby code to fill it.

Step 1: Create a template

Open LibreOffice Writer (or OpenOffice) and create a new document. Type placeholders using uppercase names surrounded by brackets:

Dear [CLIENT_NAME],

Thank you for your order on [ORDER_DATE].

Best regards,
[COMPANY_NAME]

Save the file as letter_template.odt.

Step 2: Write the Ruby code

require 'odf-report'

report = ODFReport::Report.new("letter_template.odt") do |r|
  r.add_field :client_name, "Jane Smith"
  r.add_field :order_date, "February 15, 2026"
  r.add_field :company_name, "Acme Corp"
end

report.generate("letter_output.odt")

This reads the template, replaces all [CLIENT_NAME], [ORDER_DATE], and [COMPANY_NAME] placeholders with the provided values, and writes the result to letter_output.odt.

Two ways to generate

Save to a file

Pass a file path to generate to write the output directly:

report.generate("output.odt")

Get binary data

Call generate without arguments to get the document as a binary string. This is useful in web applications where you want to send the file as a download:

binary_data = report.generate

A more complete example

Here's a template with fields, a table, and an image:

report = ODFReport::Report.new("invoice_template.odt") do |r|
  # Simple field replacements
  r.add_field :invoice_number, "INV-2026-001"
  r.add_field :client_name, @client.name
  r.add_field :date, Date.today.strftime("%B %d, %Y")

  # Table: repeats rows for each item
  r.add_table("ITEMS", @line_items, header: true) do |t|
    t.add_column(:description)
    t.add_column(:quantity)
    t.add_column(:price) { |item| format("$%.2f", item.price) }
  end

  # Image replacement
  r.add_image :company_logo, "assets/logo.png"
end

report.generate("invoice.odt")

Next steps

• Fields — learn all the ways to replace placeholders
• Tables — generate rows from collections
• Sections — repeat complex document structures
• Using with Rails — serve documents from a Rails app