cannot handle image uploads using expressjs - upload

I am using express v2.5.8. I am uploading a file from a multipart form where the file input in the form is classified as a file:
Form:
enctype="multipart/form-data"
Element:
type='file'
Within the server side app, I have set the following:
app.use(express.bodyParser({uploadDir:'./files/ph'})), //valid directory and no write issues
I have also required the 'fs' module.
Within the form handling route, I can see req.body but when I try to access req.files, it seems to be undefined & when I check the req.is('image'), the result is false.
Any suggestions on handling image uploads from a html form handled via express would be appreciated.
Thanks in advance.

I switched to node-formidable and it works for me - I will check above logic again once I use express v3.0/connect v2.0 (it seems like req.files for multipart data is available in express 3.0/connect 2.0 though I am not entirely certain so please do your own due diligence about it).

Related

Remove unused files from ActiveStorage+DirectUpload

Consider the following example:
I have a form that includes a multiple files input;
The input file uses ActiveStorage and DirectUpload to upload files automatically as soon as they are included;
After adding some files they are uploaded automatically;
I never click the submit button so those files are never used nor accessible anywhere;
Does Rails support some built-in mechanism for removing these files or is something we have to implement ourselves?
Seems rather trivial to perform a DoS by continuously uploading files until something breaks.
Update 1
Forgot to mention that the example I'm following uses a 3rd party library (Dropzone in this case) and follow the example from the official documentation.
According to the documentation after a file upload we inject a hidden input field with the id of the uploaded blob.
I think the answer of Chiperific is good, since DirectUpload is executed in the submit there is little time for the requests to fail.
I mention requests because as far as i understand it, the process is like this:
The user selects a file from his computer and fills the rest form.
DirectUpload uploads the file to the storage.
The backend receives the body and updates the attachment and either creates or updates a model.
So, what happens if the file upload is successful but model validation is not? you would end up with a file in the storage without his corresponding model or with dirty one.
More information here: https://github.com/rails/rails/issues/31985
The answer then is no, rails does not have a mechanism of removing this files automatically. I guess you could check if the model creation/update was successful and remove the file manually if not.
I think your premise is incorrect.
The input file uses ActiveStorage and DirectUpload to upload files automatically as soon as they are included;
According to the docs:
Active Storage, with its included JavaScript library, supports uploading directly from the client to the cloud.
and
That's it! Uploads begin upon form submission.
So the point of Direct Storage seems to be to bypass some Rails ActiveStorage things and go straight to the service. BUT, it still doesn't happen until the form is submitted.
The example on the non-edge docs shows the user clicking "Submit" before the files are actually uploaded.

How to upload a file from console application to MVC website?

I have an MVC application that can accept a file. It basically follows the example shown here for uploading a single file: https://www.c-sharpcorner.com/article/upload-files-in-asp-net-mvc-5/.
However, I would like to create a command line console utility from which I can upload a file. I think that I very generally understand this would likely involve creating a web request, adding certain headers, and attaching a byte array for the file but I'm a bit lost as to what this entails specifically.
Also for the console application, I will obviously modify the action to return a json result instead of a view.
Oh my gosh it was so much easier than I expected. I just used the WebClient.UploadFile() method and it worked like a charm.

Saxon CE 1.1 - Using result-document to create a output file

I've been playing with Saxon-CE_1.1 over the last few days and have managed to create a little application that allows users to classify pictures according to a data dictionary using a select dialog. All was going really well until I tried to use the result-document() function in it's "classic" way, to create a new file in the file system containing the choices the user has made.
XML Quire is returing with a severe error stating:
XpathException in mode: '{http:saxonica.com/ns/interactiveXSLT}onclick' event: [object MouseEvent]: Expected '?select=' ir '#' at start of result document href found "filename.xml
This error seems, to me, to be stating that I must pipe the results back into the HTML using # or ?select/
Is it still possible to create "external" output using SaxonCE? If so how can I accomplish the task.
Until recently it has not been possible to read or write files in the local client machine from Javascript code running in the browser, and if Javascript can't do it, then Saxon-CE can't do it either.
This may change soon with the HTML5 FileSystem API, but as far as I'm aware support for this is still very patchy. When it appears to be more stable and widespread, we can certainly look at implementing both doc() and xsl:result-document to access local filestore (or indeed, implementing the EXPath file module).

How do you perform a resumable upload to a google docs collection? Namely using Java and g-data library

I've got a working system to upload to the default root using resumable uploads and I've been able to make the meta data in a collection but I need to be able to do this type of upload straight to a collection or sub collection.
My main problem is the url, there's no defined example of a straight upload path to a collection?
I assumed that it would be like:
https://docs.google.com/feeds/upload/create-session/default/private/full/folder%3A[folder_id]/contents
considering that the typical upload path is similar except without the upload/create-session part?
In a folder entry, look for a link like this:
<link rel="http://schemas.google.com/g/2005#resumable-create-media"
type="application/atom+xml"
href="https://docs.google.com/feeds/upload/create-session/default/private/full"/>
The href is what you need to send to to create the file in that folder.
p.s. Have you considered using the new Drive API? It has this funcitonality and is considerably better to use.
Turns out I was originally correct and the URL I provided was correct for uploading but the function I created for generating the URL was missing out the / between feeds and upload

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I have a Rails application setup to receive file attachments using Paperclip.
Now I need to allow a .net/C# cell phone application to post files along with the XML in the same way (or some other way if necessary: they could encode the image as base64 and send - they tried that initially - including the binary data in the tag that would normally be a file field in the web application, but it did not work.
I have found nothing in the way of documentation and wondering if anybody has experience or advice.
Surprising that there is apparently no documentation for doing this anywhere to be found. I ended up stumbling across a document on the Basecamp website describing how their file attachment process works for API users and used it as a guideline.
http://developer.37signals.com/basecamp/
with help from this article about posting files:
http://www.codevil.com/index.php/2009/05/23/posting-and-getting-files-in-rubyrails/
I modified my initial setup so that, rather than passing the tag in the XML, they first post a file and receive an file ID in response.
Then they post the XML with that reference and their .
Then I use before_validation and after_save callbacks to set the file with Paperclip, and remove the tmp file after the save.

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