邪恶的 PDF - 图像不显示

Question

我正在使用 ruby 3.0.0 和 rails 6.1.3.2。我研究了很多示例，但还没有找到最终在 PDF 中显示图像的解决方案。 PDF 呈现（CSS 也在工作），但图像显示为 empty/not 已找到。不过，如果我去他们的URL，我可以看到他们。

澄清一下，certificate 属于 certificate_template 和 has_one_attached :pdf。 Acertificate_templatehas_one_attached :brand_logo, :signature.

# controllers/admin/certificates_controller.rb
 
    def view_pdf
      @certificate = Certificate.find(params[:certificate_id])
      if !@certificate.pdf.attached?
        pdf = WickedPdf.new.pdf_from_string(
          render_to_string(template: 'admin/certificates/view_pdf.html.erb', layout: 'application.pdf.erb')
        )
        @certificate.pdf.attach(io: StringIO.new(pdf), filename: "#{@certificate.path.title} - #{@certificate.user.name}.pdf", content_type: 'application/pdf')
      end
      
      respond_to do |format|
        format.html
        format.pdf do 
          render pdf: url_for(@certificate.pdf), content_type: 'application/pdf', template: 'admin/certificates/view_pdf.html.erb', page_size: 'A4', layout: 'application.pdf.erb', orientation: 'Landscape', zoom: 1, dpi: 75, disposition: 'inline'
        end
      end
    end

# views/admin/certificates/view_pdf.html.erb

<div class="template-frame">
  <div class="template-text">
    <br /><br />
    <%# Brand logo %>
    <% if @certificate.certificate_template.brand_logo.attached? %>
      <%= wicked_pdf_image_tag url_for(@certificate.certificate_template.brand_logo), width: '400px' %>
    <% elsif current_tenant && current_tenant.has_custom_domain? && @theme %>
      <%= wicked_pdf_image_tag url_for(@theme.brand_logo), width: '400px' if @theme.brand_logo.attached? %>
    <% end %>
    <br /><br /><br /><br />
    <%# Title and Date %>
    <div class="title-date">
      <h3 class="certificate-title serif">Certificate of Completion</h3>
      <p id="template-date" class=<%= "my-0 #{'hide-element' unless @certificate.certificate_template.show_date}"  %>>was awarded on <%= Date.today.strftime("%m/%d/%Y") %> to</p>       
    </div>

    <%# Name of user and course %>
    <div class="user-course">
      <div class="user-hr">
        <h3 class="serif name"><%= @certificate.user.name %></h3>
        <hr>
      </div>
      <br />
      <p class="for-completing">for completing the course</p>
      <h3 class="serif course-name"><%= @certificate.path.title %></h3>
      <p class=<%= "#{'hide-element' unless @certificate.certificate_template.show_course_description} course-description"  %>>
        <%= @certificate.certificate_template.course_description %>
      </p>
    </div>
    <%# Signature %>
      <br /><br /><br /> <br />
    <div class="template-signature" class=<%= "hide-element" unless @certificate.certificate_template.show_signature %> >
      <% if @certificate.certificate_template.signature.attached? %>
        <%= wicked_pdf_image_tag url_for(@certificate.certificate_template.signature), width: '400px' %>
      <hr>
      <p class="serif"><%= @certificate.certificate_template.printed_name %></p>
      <p><%= @certificate.certificate_template.printed_position %></p>
      <% end %>  
    </div>
  </div>
</div>

# views/layouts/application.pdf.erb

<!DOCTYPE html>
<html>
  <head>
    <title>Certificate</title>
    <meta name="viewport" content="width=device-width,initial-scale=1">
    <%= wicked_pdf_stylesheet_link_tag "pdf" %>
    <%= csrf_meta_tags %>
    <%= csp_meta_tag %>
  </head>
  <body>
    <%= yield %>
  </body>
</html>

Answer 1

在尝试了各种解决方案后，以下是对我有用的方法：

<%= wicked_pdf_image_tag(polymorphic_url(@certificate.certificate_template.brand_logo), width: "400px") %>

邪恶的 PDF - 图像不显示

Wicked PDF - images are not showing

ruby

ruby-on-rails

wicked-pdf