custom_schema.rb

# frozen_string_literal: true

# Custom fields on top of a preset, fields injected into every line-item row, and saving
# the combination so later calls are one argument.
#
#   ruby examples/custom_schema.rb invoice.pdf

require "vision_api"

path = ARGV[0] || "invoice.pdf"
vision = VisionAPI.new

schema = {
  # Plain form: the string is the description. Descriptions are the prompt — the more
  # precisely you say what you want, the better the extraction.
  "machine_serial" => 'Serial number of the machine being invoiced, without the "SN:" prefix',

  # Typed form. Numbers come back as JSON numbers, dates as ISO YYYY-MM-DD.
  "total_net" => { "type" => "number", "description" => "Total before tax" },
  "is_paid" => { "type" => "boolean", "description" => "Whether the invoice is marked PAID" },
  "reference_numbers" => { "type" => "array", "description" => "All reference numbers", "items" => "string" },

  # "line_item" is reserved: these become extra columns on every row of the preset's
  # line-item array. Only meaningful with a preset that has line items; with a bare custom
  # schema there is nothing to inject into.
  "line_item" => { "lot_number" => "The lot number printed on this line, if present" }
}

res = vision.analyze(file: path, preset: "invoice", schema: schema)
result = res["result"]

puts "serial: #{VisionAPI::Result.value(result, 'machine_serial')}"
puts "net total: #{VisionAPI::Result.value(result, 'total_net')}"
puts "paid: #{VisionAPI::Result.value(result, 'is_paid')}"

VisionAPI::Result.rows(result, "line_item").each do |row|
  line = VisionAPI::Result.unwrap(row)
  puts "  #{line['quantity'] || '?'} × #{line['description'] || '(no description)'} " \
       "= #{line['amount'] || '?'}  [lot #{line['lot_number'] || '—'}]"
end

# Save it, and the next call is schema_name: "our-invoices". The definition is compiled
# before it is stored, so an invalid schema fails here rather than on the first extraction
# that uses it.
begin
  vision.create_schema("our-invoices", preset: "invoice", schema: schema)
  puts %(\nsaved as "our-invoices")
rescue VisionAPI::ConflictError
  vision.update_schema("our-invoices", preset: "invoice", schema: schema)
  puts %(\nupdated "our-invoices")
end

again = vision.analyze(file: path, schema_name: "our-invoices")
puts "same fields via the saved schema: #{again['result'].size}"