Module: S3lurp::ViewHelpers

Defined in:
lib/s3lurp/view_helpers.rb

Constant Summary collapse

HIDDEN_FIELD_MAP = 
{
  :key => 'key',
  :aws_access_key => 'AWSAccessKeyId',
  :acl => 'acl',
  :cache_control => 'Cache-Control',
  :content_type => 'Content-Type',
  :content_disposition => 'Content-Disposition',
  :content_encoding => 'Content-Encoding',
  :expires => 'Expires',
  :success_action_redirect => 'success_action_redirect',
  :success_action_status => 'success_action_status'
}
NON_FIELD_OPTIONS = 
%w( s3_bucket aws_secret_key
max_file_size min_file_size
amz_meta_tags minutes_valid
form_html_options file_field_tag_accept
submit_tag submit_tag_value submit_tag_options).map(&:to_sym)

Instance Method Summary collapse

Instance Method Details

#s3_direct_form_tag(opt = {}) ⇒ Object 



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# File 'lib/s3lurp/view_helpers.rb', line 25

def s3_direct_form_tag(opt = {})
  options = (NON_FIELD_OPTIONS + HIDDEN_FIELD_MAP.keys).each_with_object({}) do |i, h|
    h[i] = opt[i] || S3lurp.config.send(i)
  end

  # configurable fields the field map is formed as {:configuration_name => "input_field_name"}
  hidden_fields = HIDDEN_FIELD_MAP.each_with_object({}) do |(k,v), h|
    h[k] = options[k] unless options[k].nil? || options[k].blank?
  end

  amz_meta_tags = options[:amz_meta_tags].is_a?(Hash) ? s3_generate_amz_meta_tags(options[:amz_meta_tags]) : {}

  # generate an expiration date for the policy
  minutes = Integer(options[:minutes_valid]) rescue 360
  expiration_date = minutes.minutes.from_now.utc.strftime('%Y-%m-%dT%H:%M:%S.000Z')

  security_fields = {}
  if hidden_fields[:aws_access_key] # only generate security fields when necessary
    security_fields[:policy] = Base64.encode64(
      s3_generate_policy(
        hidden_fields.clone,
        { :meta_tags => amz_meta_tags,
          :s3_bucket => options[:s3_bucket],
          :expiration => expiration_date,
          :min_file_size => options[:min_file_size],
          :max_file_size => options[:max_file_size]
        }
    )).gsub(/\n/,'')
    security_fields[:signature] = Base64.encode64(
      OpenSSL::HMAC.digest(
        OpenSSL::Digest::Digest.new('sha1'),
        options[:aws_secret_key], security_fields[:policy])
    ).gsub(/\n/,'')
  end

  amz_meta_tags.merge! security_fields
  submit = s3_generate_submit_tag(options)
  file = s3_generate_file_field_tag(options)
  form_tag("http://s3.amazonaws.com/#{options[:s3_bucket]}",  {:authenticity_token => false, :method => 'POST', :multipart => true}.merge(options[:form_html_options])) do
    (
    hidden_fields.map{|k,v| hidden_field_tag(HIDDEN_FIELD_MAP[k],v, {:id => nil})}.join.html_safe +
    amz_meta_tags.map{|k,v| hidden_field_tag(k,v,{:id => nil})}.join.html_safe +
    field_set_tag(nil,:class=>"s3lurp_file") {file} +
    field_set_tag(nil,:class=>"s3lurp_submit") {submit.html_safe}
    )
  end
end

#s3_generate_amz_meta_tags(meta = {}) ⇒ Object 



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# File 'lib/s3lurp/view_helpers.rb', line 101

def s3_generate_amz_meta_tags(meta = {})
  meta.each_with_object({}) do |(k,v), hash|
    hash[%(x-amz-meta-#{k})] = v
  end
end

#s3_generate_file_field_tag(opt = {}) ⇒ Object 



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# File 'lib/s3lurp/view_helpers.rb', line 118

def s3_generate_file_field_tag(opt ={})
  if opt[:file_field_tag_accept]
    file_field_tag('file', :accept => opt[:file_field_tag_accept], :class => 's3lurp_file_tag')
  else
    file_field_tag('file', :class => 's3lurp_file_tag')
  end
end

#s3_generate_policy(fields = {}, options = {}) ⇒ Object 



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# File 'lib/s3lurp/view_helpers.rb', line 73

def s3_generate_policy(fields = {}, options = {})
  fields.delete(:aws_access_key)
  conditions = [
    { :bucket => options[:s3_bucket]},
    ['content-length-range', options[:min_file_size], options[:max_file_size]],
    ['starts-with', '$utf8', ""]
  ]
  HIDDEN_FIELD_MAP.each do |field, field_name|
    next unless fields[field]
    case field
    when :key
      key = fields[field].gsub(/\/?\$\{filename\}\/?/,'')
      conditions.push ["starts-with", "$key", key]
    else
      conditions.push ({ field_name => fields[field] })
    end
  end
  if options[:meta_tags]
    options[:meta_tags].each do |k,v|
      conditions.push ["starts-with", "$#{k}", '']
    end
  end
  policy = {
    "expiration" => options[:expiration],
    "conditions" => conditions
  }.to_json
end

#s3_generate_submit_tag(opt = {}) ⇒ Object 



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# File 'lib/s3lurp/view_helpers.rb', line 107

def s3_generate_submit_tag(opt = {})
  opt[:submit_tag_options].update(:name => nil)
  if opt[:submit_tag]
    opt[:submit_tag]
  elsif opt[:submit_tag_value]
    submit_tag(opt[:submit_tag_value], opt[:submit_tag_options])
  else
    submit_tag("Upload", opt[:submit_tag_options])
  end
end