Rails download file from url s3 without opening

That way involved just fetching the headers of a url before actually downloading it. This allows us to skip downloading files which weren't meant to be downloaded.

To restrict download by file size, we can get the filesize from the Content-Length header and then do suitable comparisons. We can parse the url to get the filename. This will be give the filename in some cases correctly. However, there are times when the filename information is not present in the url. In that case, the Content-Disposition header will contain the filename information. Here is how to fetch it.

The url-parsing code in conjuction with the above method to get filename from Content-Disposition header will work for most of the cases. Use them and test the results. These are my 2 cents on downloading files using requests in Python. Let me know of other tricks I might have overlooked.

This article was first posted on my personal blog. Especially if the files are big. That is good idea and using with as a context manager is more better and looks great. Their service for files is Simple Storage Service. If you don't already have an AWS account, you'll need to head over there and sign up. S3 stores your files in buckets, once you have an account setup, you should create a bucket , probably per environment but starting with development, to use with your application to store your files in.

Now that we have a bucket, we need to connect the application to S3. This means configuration to manage. As ever, I always reach for dotenv to manage my environment variables in a Rails app.

So we need to add it to our Gemfile:. We now have dotenv in our Rails application which means we are ready to configure our connection to S This is the information you'll need from your S3 account to be able to connect to your bucket.

Now that we have the information that we need, we need to tell Paperclip to use S3 instead of our file system on the application server. There are a few ways that you can connect to your bucket using Paperclip.

I prefer setting default settings that are loaded when your application loads:. As you can probably tell, the section that we've added here to the default application. If you have more than one Paperclip class in your application, you might not want to go with this approach, or you can just override any settings in another class if you need. Most of the stuff in here is pretty self-explanatory. It's all our settings that we have set up in our. Now that we have our configuration to connect Paperclip with S3, we need to tell the Image class what it needs to know to use it.

Let's have a look at the changes we need:. Let's go through the changes that we have here. These let our app know where to put our image when we upload it, and how what URL to use after it is uploaded. In 10 seconds that URL will no longer work, and anyone using it will get an Access denied message from S3. Is the same, except we are giving someone a little longer to sort out their download, and it is explicitly asking for the original.

Leaving your bucket open to the public is a serious security threat. Similarly, you can retrieve a download URL from a show action:. This means your files are totally wide open i.

The method creates a temporarily authenticated url set to expire after 10 seconds. Files can be served either privately via signed URLs or publicly via an to detect one of the vulnerable setups without actually modifying the data.