I am attempting to use Imagemagick to manipulate images that are uploaded by a user. Right now I have a simple set of Imagemagick.convert[ ] commands server side that preform a variety of tasks on the uploaded image. My problem comes from Imagemagick needing the file data to be read into meteor and not from a url. What I end up doing is writing the uploaded file to the /public folder where Imagemagick is able to manipulate the image. However because the list of Imagemagick.convert commands (saving and writing to /public), the application keeps refreshing, breaking up the processes and sending it into an infinite refreshing cycle. I don't think assets is a viable solution, but I need some folder that I can write to in meteor that will not interrupt the various Imagemagick processes through a refresh. I have tried the .folder for a hidden folder, but meteor gives me an error: "You can’t use a name that begins with a dot “.”, because these names are reserved for the system. Please choose another name." Any thoughts?
#Nate I wrote a little example app that solves this problem by using a temporary directory (as others have suggested):
https://github.com/ideaq/image-uploads
My solution gives you:
Easy image uploading in any Meteor app
Images are re-sized to Thumbnail, Mobile Optimised and Full-size Original
Images are uploaded to AWS S3 for CDN delivery (scalability and speed)
A thumbnail of the image is displayed on to the user without refreshing the page
if you found a better way of doing image uploads in meteor, please share! thanks. :-)
Related
In my application, users can change the background image of a banner. They upload the file using Simple Form and Active Storage. It's working correctly but we had a user trying to upload a file name banner-website.png (2).png. The file is uploaded and saved but doesn't appear as a background image. I guess this happens because of special characters in the filename.
What is recommended to avoid such situations? Do we need to sanitize file names?
Several things to check:
Check the console and tried to view the CSS and see if the full link
is being populated? Try checking the CSS code and copy the link to
an address bar to see if the image loads from that direction.
Check the users png file to make sure its not corrupt. PNG headers that are corrupt can cause issues displaying in a website.
Check to see if your sanitizing plugin is causing an issue with that file. I have never used that one so regarding that I cannot say.
I tried uploading a file with a same name into my Rails 6 testbench (vanilla with active storage and stimulus js) and it works fine. It could be a conflicting CSS code too.
Just my 2 cents.
I've found the solution here: Rails Active Storage - Background Image invalid property?
Adding a single quote around the URL solved it.
I am working on an App, in which I want to upload images and pdf to the FTP server. I am using this reference ref.All is working good. The images and pdf are getting uploaded on the server with proper names and sizes.
But, now I want to check if the directory is already exists on the server or not. I am not able to get it to work with this library.
So my question is that how to check directory on ftp,if directory is there then upload the files if not then first create directory on ftp and then upload files onto that directory?
Any Ideas.. ? Any help will be appreciated.
Different FTP servers will answer the LIST request in differing ways, so there is no single answer to this question. RFC959 says on the matter:
Since the information on a file may vary widely from system
to system, this information may be hard to use automatically
in a program, but may be quite useful to a human user.
Using the CWD request to change into the directory in question, and detecting a successful response will detect the directory, however that leaves you in that directory as a potentially unrequired side effect.
For these reasons, as well as others, you may find more modern protocols such as SSH (which includes a file transfer feature) to be more useful. You may find the DLSFTPClient CocoaPod useful.
M.
For a rails app that works a lot with uploaded image heavy pdf files I'm looking for a way to optimize the file size of uploaded pdf's.
Adobe Acrobat has a 'save as reduced file size pdf' option which often halves the filesize when images are included.
I would like to do a similar action that is triggered after a file upload in my rails app.
Any ideas?
While #lzap's comment may be true, if you still want to give it a shot, you might look at pdftk (PDF Toolkit). Its a library for manipulating and creating PDF files that looks like it offers the ability to compress a given pdf file.
The library can be installed on most major operating systems, so if you have the ability to install it on your host, then simply call:
system("pdftk uncompressed-input.pdf output compressed-outpu.pdf compress")
inside your rails app whenever you want to compress a particular PDF file. I have no idea how long this would take, and if you are compressing many PDF's at the same time, you may want to consider handing off to a background job (without this, Rails will wait until the compression is done before returning anything to the browser, probably causing a timeout error for long running groups of compression calls).
Also, if your file names come from user input, be extra careful to avoid injection attacks.
Currently image_tag("file.jpg") produces normal image html tag, BUT src="file.jpg**?7485793246**" What are those numbers anyway and how to disable them?
Those are refered to as Asset Timestamps they can be used by the server to cache files. For example lets say you have a file called file.jpg on your server, you can set up your server to tell browsers like firefox to cache the file.jpg so the next time that browser visits your web-page it loads faster because file.jpg was already in memory.
The problem comes when you upload a new file.jpg because even though the image is different, your old users who have the image cached will still see the cached image, that is where asset timestamps come into play. Those numbers represent a timestamp of when the file was updated, so if you replace file.jpg?123456789 with file.jpg?987654321 then the user's browser will not use the cached version.
http://api.rubyonrails.org/classes/ActionView/Helpers/AssetTagHelper.html
long story short, it is only there to help you, and doesn't affect the way the file behaves at all. Users can still download the file and operating systems will see it as being a valid .jpg.
thats your development mode making sure that nothing gets cached so that if you change the image it actually gets to the browser. the production version won't have it.
Solved, add this to environment.rb => ENV['RAILS_ASSET_ID'] = ''
Conclusion: yes, its a good rails stuff, but when you deal with ie6 and PNG images it can break your script. So be careful.
I'm working on a Rails app that accepts file uploads and where users can modify these files later. For example, they can change the text file contents or perform basic manipulations on images such as resizing, cropping, rotating etc.
At the moment the files are stored on the same server where Apache is running with Passenger to serve all application requests.
I need to move user files to dedicated server to distribute the load on my setup. At the moment our users upload around 10GB of files in a week, which is not huge amount but eventually it adds up.
And so i'm going through a different options on how to implement the communication between application server(s) and a file server. I'd like to start out with a simple and fool-proof solution. If it scales well later across multiple file servers, i'd be more than happy.
Here are some different options i've been investigating:
Amazon S3. I find it a bit difficult to implement for my application. It adds complexity of "uploading" the uploaded file again (possibly multiple times later), please mind that users can modify files and images with my app. Other than that, it would be nice "set it and forget it" solution.
Some sort of simple RPC server that lives on file server and transparently manages files when looking from the application server side. I haven't been able to find any standard and well tested tools here yet so this is a bit more theorethical in my mind. However, the Bert and Ernie built and used in GitHub seem interesting but maybe too complex just to start out.
MogileFS also seems interesting. Haven't seen it in use (but that's my problem :).
So i'm looking for different (and possibly standards-based) approaches how file servers for web applications are implemented and how they have been working in the wild.
Use S3. It is inexpensive, a-la-carte, and if people start downloading their files, your server won't have to get stressed because your download pages can point directly to the S3 URL of the uploaded file.
"Pedro" has a nice sample application that works with S3 at github.com.
Clone the application ( git clone git://github.com/pedro/paperclip-on-heroku.git )
Make sure that you have the right_aws gem installed.
Put your Amazon S3 credentials (API & secret) into config/s3.yml
Install the Firefox S3 plugin (http://www.s3fox.net/)
Go into Firefox S3 plugin and put in your api & secret.
Use the S3 plugin to create a bucket with a unique name, perhaps 'your-paperclip-demo'.
Edit app/models/user.rb, and put your bucket name on the second last line (:bucket => 'your-paperclip-demo').
Fire up your server locally and upload some files to your local app. You'll see from the S3 plugin that the file was uploaded to Amazon S3 in your new bucket.
I'm usually terribly incompetent or unlucky at getting these kinds of things working, but with Pedro's little S3 upload application I was successful. Good luck.
you could also try and compile a version of Dropbox (they provide the source) and ln -s that to your public/system directory so paperclip saves to it. this way you can access the files remotely from any desktop as well... I haven't done this yet so i can't attest to how easy/hard/valuable it is but it's on my teux deux list... :)
I think S3 is your best bet. With a plugin like Paperclip it's really very easy to add to a Rails application, and not having to worry about scaling it will save on headaches.