Yo,
I've got attachment_fu set up on my server, and it works just fine. My goal, however, is to be able to upload PDFs and have them convert to image (then use all the pre-built attachment_fu options like resize and thumb produce the desired images). What currently happens is that PDFs upload and remain PDFs, whereas images go through all the motions of resizing and whatnot.
How can I get the functionality I want? Is there a simple way to go about doing this using the tools I already have, or should I just manually invoke RMagick to do the initial conversion? If so, how can I do that and then pass off the file to attachment_fu for handling?
Thanks,
--Matchu
For the oldest unanswered rails question: https://stackoverflow.com/a/69804/156561 his answer is probably very similar to get you in the door to use Attachment_fu which I'm sure you've by now migrated off.
Related
I have a slider which shows some custom made images on the main site.
At the moment every time I want to change something I need to deploy a new image with the changed text.
I was wondering if there is a gem which can be settled up to put some custom text over a default image if several conditions are met.
To do any kind of programatic image manipulation I would look at imagemagick. Think of photoshop in an open source binary. As imagemagick has been written in C you will not be able to call it directly. Instead use rmagick. Rmagick provides a nice ruby interface around imagemagick's c based API. There might be an updated way to do this as I have not worked with images in ruby for years however it's the best place to start. GL.
I'm aware of pdf-stamper, but I'm trying to avoid switching everything to jruby right now.
I just need to "stamp" an image that I generate within the rails app (a PDF417 barcode) into a form field in the PDF document (there's an FDF; it's a document template kinda thing).
I'm filling out the text-based fields by just shelling out to pdftk, so if there's a way to do it using pdftk, I'd be fine with that, but I've looked high and low for one without any luck.
How about using a barcode font? some alternatives too. I haven't used that one but there may be others available too
I know I'm late to the party, but the PDF417 Rubygem should do what you need. https://rubygems.org/gems/pdf417 will generate it and if you have chunky_png installed you can easily write out PNGs to a file.
I'm creating a Facebook app using Rails and hosted on Heroku and I'm having a bit of trouble finding the ideal way to solve a problem. I want the user to be able to move their photos around on the screen, position them, and then download that as either a PDF or a PNG file to be emailed or printed. I have the app getting the user's facebook photos and they can drag them on to a HTML5 Canvas element to position them. Taking this canvas, however, and converting it into something printable is where I'm hitting a dead end.
Basically I have a few ideas I have tried:
Convert the Canvas to a PNG using toDataURL() - Would work perfectly but since the photos are external, the canvas is "dirty" and will throw up a security issue. I've thought about trying to copy the pixels of each image to a pixel array but I've heard this may not work either due to security issues. Since the app is dealing with people's facebook images I really don't want to store them on the app's server.
Use PDFKit/wkhtmltopdf to create a PDF using Rails - I've tried this, but since the app is a Sinatra app (I think), it's confusing me a lot. It's throwing errors with the to_pdf call saying 'Command Failed'. I've tried adding a config.middleware.use line but I'm not 100% sure where to put it and everywhere seems to be failing saying "config" is an undefined variable. Also installing wkhtmltopdf seems to fail on Heroku once I test it outside localhost.
Use Prawn to create a PDF using Rails - I've tried prawn but it seems to have a similar problem to PDFKit and I get confused about what goes where on a Sinatra app. I'm sure I read as well that people were having problems with it too.
Have I missed any obvious solutions to this, or is there something I'm not thinking of? All I want to do is create some kind of easily printable file with positioning intact that can be easily downloaded and printed by the user but I've come across so many problems that I don't know where to go next and I'm going round in circles.
If anyone had any advice for me about how I could get around this problem I'd really appreciate it.
if prawn is giving you grief just use one of the jquery plugins to print your div content. You could even configure a pdf printer and print the document instead of hard copy if you so wish/need images in pdf format.
I use http://archive.plugins.jquery.com/project/jqPrint plugin in one of my projects and it works like a charm.
It sounds like many of your issues relate to the necessary PDF binaries not being accessible on Heroku. In following with the twelve factor approach to dependency isolation Heroku purposely provides a very bare system.
If you need to run a custom binary on Heroku I'd suggest looking at a tool called Vulcan which can compile a binary that's compatible with the Heroku runtime.
So, the thing is. I'm building my first rails app which reads images from a directory and it's subdirs. Now, I want to generate dynamic thumbnails of those images. But I don't want to fill up that directory with the thumbnail images. I was thinking of caching these thumbs separately for each user in temporary directory.
Oh, and, I would also need the dimensions of the images for some css magic.
What plugins/gems/... should I use to accomplish this?
You should rmagick coupled with Paperclip. In this way you can specify the dimensions (and many other attributes of the images), and make thumbnails on the fly.
On top of this, I would also add in delayed_job which will background the process of the images so if any of them are provided by the client, they won't have to wait for it to complete client-side.
rMagick : http://github.com/rmagick/rmagick
Paperclip: http://github.com/thoughtbot/paperclip
delayed_job: http://github.com/collectiveidea/delayed_job
How do I upload images and zip files in RoR? I am a newbie. So please help.
Give me both the view and the controller code example.
Thanks in advance.
Nav,
Try the paperclip plugin, you can read about it here http://www.thoughtbot.com/projects/paperclip
We prefer CarrierWave for image uploads in Rails. Very easy to integrate and very modular.
The following post describes a solution for image uploading using CarrierWave while image transformations are done seamlessly in the cloud. Uploaded images are stored in the cloud and delivered through a CDN.
No need to install RMagick, MiniMagick and ImageMagick.
http://cloudinary.com/blog/ruby_on_rails_image_uploads_with_carrierwave_and_cloudinary
suggest checking out the Railscast for paperclip.
ImageMagick is also pretty cool
I would recommend paperclip, and the patch that allows you to store the content in the database instead of the file system
http://patshaughnessy.net/paperclip-database-storage
the link has the view and controller examples that you are looking for
I prefer carrierwave is better to upload images easily.
Here's github page , and railscasts page for quick start.
One option is attachment_fu. It allows you to save your uploaded file to the filesystem, database, or Amazon S3. It also allows you to select which image processor is used, such as RMagick or Minimagick.
The link provides better code than I could here.