WickedPDF Rendering differently locally vs production - ruby-on-rails

Question

I have installed wkhtmltopdf 0.12.3 (with patched qt) on my desktop machine and the exact same version on my Centos virtual machine.
I am using WickedPDF and Rails to convert HTML to PDF.
When the PDF is generated it has slight differences in the font. Some weird letter spacing. I have attached images showing this.
You can see the gap between the e and n this however is not present on my local machine. Image below:
Does anyone know why this would happen?
Any advice would be appreciated.
Thanks
This is the Ruby code which I am using to generate the PDF with WickedPDF
def generate_pdf
pdf = WickedPdf.new
pdf_file = pdf.pdf_from_string(ActionController::Base.new().render_to_string('card_requests/show.pdf.haml', layout: 'pdf', locals: {card_request: self}),
dpi: '300',
margin: {top: 0, bottom: 0, left: 0, right: 0},
page_height: '2.25in',
page_width: '3.75in',
disable_smart_shrinking: false
)
tempfile = Tempfile.new(["#{self.name.gsub(' ', '_').downcase}_biz_card", '.pdf'], Rails.root.join('pdfs'))
tempfile.binmode
tempfile.write pdf_file
tempfile.close
self.pdf = File.open(tempfile.path)
tempfile.unlink
self.save
end
Here is also the show.pdf.haml file with the CSS at the top:
!!! 5
%html
%head
:css
html * {
margin: 0 !important;
padding: 0 !important;
page-break-inside: avoid !important;
}
body {
margin: 0 !important;
padding: 0 !important;
page-break-inside: avoid !important;
text-rendering: optimize-speed;
}
.card-preview {
font-family: 'TradeGothic';
background-size: contain;
width: 369px;
height: 220px;
page-break-after: avoid !important;
position: relative;
}
#card-name {
color: #ED1D27;
font-weight: bold;
font-size: 12pt;
position: absolute;
top: 37px;
left: 39px;
width: 328px;
}
#card-title {
color: #2E2D2D;
font-weight: bold;
position: absolute;
top: 54px;
left: 39px;
font-size: 9pt;
}
#card-office-phone {
color: #4e4e48;
position: absolute;
top: 148px;
left: 39px;
font-size: 8.5pt;
}
#card-cell-phone {
color: #4e4e48;
position: absolute;
top: 135px;
left: 39px;
font-size: 8pt;
width: 200px;
}
#card-email {
color: #4e4e48;
position: absolute;
top: 161px;
left: 39px;
font-size: 8.5pt;
}
#card-website {
color: #4e4e48;
position: absolute;
top: 174px;
left: 39px;
font-size: 8pt;
}
.hide {
display: none;
}
%meta{:charset => "utf-8"}
%body
.card-preview{style: "background-image: url('#{Rails.root.join('app', 'assets', 'images', 'card_template_2.svg')}')"}
#card-name
= card_request.name
#card-title
= card_request.title
#card-office-phone{class: (card_request.office? ? "" : 'hide')}
== office 555 555 5555 #{card_request.ext? ? "ext #{card_request.ext_phone}" : ''}
#card-cell-phone{class: ((card_request.cell? && !card_request.cell_phone.blank?) ? "" : 'hide'), style: (card_request.office? ? "" : 'top: 148px; left: 39px;')}
= (card_request.cell? ? "cell 555 555 5555" : '')
#card-email
= card_request.email
#card-website
www.website.com
I have since fixed this issue by following this:
https://taskman.eionet.europa.eu/issues/20890
It fixes kerning issue on CentOS for me.

Answer 1

I was facing a similar issue of spaces after certain specific letters like
Reg istration ---> space after letter 'g'
O pen ---> space after Capital letter 'O'
The above issue could be due to system specific fonts configs. I referred an issue reported over github for the same https://github.com/wkhtmltopdf/wkhtmltopdf/issues/45
This issue occurs on a production instance (AWS AMI linux) with CentOS 6.x but was working perfectly with ubuntu 14.04. I looked into the system fonts configs 51-local.conf over CentOS at path /etc/fonts/conf.d .If there is no file with name wkhtmltopdf at the same path then use the default fonts file 51-local.conf to have the below configuration as custom fonts.
<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
<fontconfig>
<match target="font">
<edit mode="assign" name="rgba">
<const>rgb</const>
</edit>
</match>
<match target="font">
<edit mode="assign" name="hinting">
<bool>true</bool>
</edit>
</match>
<match target="font">
<edit mode="assign" name="hintstyle">
<const>hintslight</const>
</edit>
</match>
<match target="font">
<edit mode="assign" name="antialias">
<bool>true</bool>
</edit>
</match>
<match target="font">
<edit mode="assign" name="lcdfilter">
<const>lcddefault</const>
</edit>
</match>
</fontconfig>
Also, If you are using wicked_pdf.rb initializer configuration exec path as /usr/local/bin/wkhtmltopdf for development environment. try to replace the path with /bin/wkhtmltopdf for production bundle