Question

抱歉我的英语，不是我的母语。

我需要创建一个PDF文件（我现在可以渲染），然后使用paperclip保存它（已经安装并与其他模型一起使用）

我找到了这个解决方案：

https://github.com/thoughtbot/paperclip/wiki/PDF-Email-Attachments-with-Paperclip-and-wicked_pdf

但它使用已经创建的报告，我需要在每次创建新记录时创建此PDF，我得到“没有nill类的方法，所以可能这就是为什么不适合我。

我尝试在“if @ instrument.save”中添加此方法，但没有用。

让我告诉你我的代码：

instrument.erb

class Instrument < ActiveRecord::Base

  belongs_to :evaluation
  has_attached_file :instrument_document
  validates_attachment :instrument_document, content_type: { content_type: "application/pdf" }
  do_not_validate_attachment_file_type :instrument_document

end

仪器＃节目

 def show
    respond_to do |format|
      format.html { redirect_to instruments_url }
      format.pdf do
        render  :pdf => "file.pdf", :template => 'instruments/instrument_document.html.erb', :margin => {:top => 15, :bottom =>15 },:header => {   html: {            template: 'instruments/header.pdf.erb', }}, :footer => { right: '[page]' }
      end 
    end
  end

仪器＃创建

  def create
    @instrument = Instrument.new(instrument_params)

    respond_to do |format|
      if @instrument.save

        # create an instance of ActionView, so we can use the render method outside of a controller
        av = ActionView::Base.new()
        av.view_paths = ActionController::Base.view_paths

        # need these in case your view constructs any links or references any helper methods.
        av.class_eval do
          include Rails.application.routes.url_helpers
          include ApplicationHelper
        end

        pdf_html = av.render template: 'instruments/instrument_document.html.erb'

        # use wicked_pdf gem to create PDF from the doc HTML
        doc_pdf = WickedPdf.new.pdf_from_string(
          pdf_html,
          page_size: 'Letter',
          javascript_delay: 6000
          )

        # save PDF to disk
        pdf_path = Rails.root.join('tmp/reports', "#{@instrument.id}_#{Date.today.iso8601}.pdf")
        File.open(pdf_path, 'wb') do |file|
          file << doc_pdf
        end

        @instrument.instrument_document = File.open pdf_path
        @instrument.save!

        # The report has now been saved elsewhere using Paperclip; we don't need to store it locally
        File.delete(pdf_path) if File.exist?(pdf_path)


        format.html { redirect_to @instrument, notice: 'Instrumento creado con éxito.' }
        format.json { render :show, status: :created, location: @instrument }
      else
        format.html { render :new }
        format.json { render json: @instrument.errors, status: :unprocessable_entity }
      end
    end
  end

我得到了：

nil的未定义方法`评估'：NilClass

谢谢！

Answer 1

日志表明未创建@instrument，不关于 Paperclip 或 wicked_pdf 。请检查创建此变量的代码。

这对我有用;就我而言，我想做的事情非常接近你。

# pdf is the name of a pdf template ex.: invoice.pdf.erb
def generate_pdf (pdf) 
 html = render_to_string_with_wicked_pdf(:pdf => pdf,
      :template => pdf,
      :layout => 'application.pdf.html',
      :encoding => 'UTF-8',
      :page_size        => 'A4',
      :dpi              => '300',
      :print_media_type => true,
      :no_background    => true,
      :margin => {
              :top => 50,
              :bottom => 25
           },
      :header => { :html => { :template => 'layouts/pdf-header.html' },
                   :spacing => 10,
                   :margin => {
                           :top => 40
                        }
                 },
      :footer => { :html => { :template => 'layouts/pdf-footer.html' } }
  )
end

此方法将pdf呈现为字符串。下一步是将这个pdf保存到这样的模型中：

 class Invoice < ActiveRecord::Base
    belongs_to :product
    has_attached_file :invoice_pdf
    validates_attachment_content_type :invoice_pdf, :content_type =>["application/pdf"]
    validates_attachment_size :invoice_pdf, :less_than => 5.megabytes
 end

这是控制器的一部分：

  invoice = Invoice.new
  invoice.product_id=@product.id
  invoice.invoice_pdf = StringIO.new(generate_pdf("product/invoice.pdf.erb")) #mimic a real upload file
  invoice.save!

使用wickedpdf创建PDF并使用paperclip保存

1 个答案: