toggl_to_invoiced.rb

require 'rubygems'
require 'httparty'
require 'active_support/all'

class TogglClient
  USER_AGENT = "TogglToInvoicedGuide"

  include  HTTParty
  base_uri "https://toggl.com/reports/api/v2/"

  def initialize(api_token)
    @basic_auth = { username: api_token, password: "api_token" }
  end

  def summary_report(workspace_id, since_date, until_date)
    options = {
      workspace_id: workspace_id,
      since:        since_date.strftime("%Y-%m-%d"),
      until:        until_date.strftime("%Y-%m-%d"),
      user_agent:   USER_AGENT,
      grouping:     "clients"
    }
    self.class.get("/summary", basic_auth: @basic_auth, query: options)
  end

end

class InvoicedClient
  include HTTParty
  base_uri "https://api.invoiced.com"

  def initialize(api_key)
    @basic_auth = { username: api_key, password: "" }
  end

  def create_invoice(invoice_attributes)
    self.class.post("/invoices", basic_auth: @basic_auth, body: invoice_attributes.to_json, headers: { "Content-Type" => "application/json" })
  end

  def list_customers
    self.class.get("/customers", basic_auth: @basic_auth)
  end

end

toggl    = TogglClient.new("YOUR_API_TOKEN")
invoiced = InvoicedClient.new("YOUR_API_KEY")

report = toggl.summary_report(YOUR_WORKSPACE_ID, 1.month.ago.beginning_of_month, 1.month.ago.end_of_month)

client_name   = "Pied Piper"
client_group  = report.parsed_response["data"].detect { |group| group["title"]["client"] == client_name }

invoice_items = client_group["items"].map do |item|
  {
    description: item["title"]["time_entry"],
    unit_cost:   item["rate"] || 100,
    quantity:    item["time"] / 1000
  }
end

customer_response = invoiced.list_customers
invoiced_customer = customer_response.parsed_response["customers"].detect { |c| c["name"] == client_name }

invoice_details = {
  name:     "Invoice for #{1.month.ago.beginning_of_month.strftime("%B")}",
  customer: invoiced_customer["id"],
  items:    invoice_items
}

result = invoiced.create_invoice(invoice_details)
puts result.inspect