We Keep Coding

How to make a link to download a server file on the browser?

I am trying to create a simple download link
The file I want to download is a .pdf that the user can upload, and now I want to make it possible to download. With the pop-up box, you know, or just on the chrome download bar
I've tried what every answer says:
Download PDF
But that leads to "Failed - no file", even though when I check
if(file_exists($GUIDELINES_PDF_DIR . $projectId . '.pdf'))
it returns true!
Some other notes:
I'm pretty shaky on server things, so maybe the same link doesn't work on PHP and on HTML? In that case, how can I find the file?
This link is within a <form>, so I don't really want to create another <form> inside it, or do anything that compromises the info that the user has inputed
Thank so much :)

$GUIDELINES_PDF_DIR is a directory on your server's hard disk.
The resulting path you are creating is relative to the root of your server's hard disk and not to the DocumentRoot of your web server.
You need to account for that difference when generating your URL.

Use a right headers:
header("Content-type:application/pdf");
header("Content-Disposition:attachment;filename='downloaded.pdf'");

Saving user uploaded image to folder and/or server

I have an app, that allows users to upload an image, crop it and with other data save it all as html file to be used as a footer for emails. The image is given to them as base64.
Howver turns out this is not supported by Outlook, since it doesnt accept b64 data as img source.
So my idea was to save the cropped image to a file, let's say /public/avatars/avatar.png and link it's directory as a source. However I'm having trouble finding a way how to save images to to a file using JS. My allowed stack is JS and React, no node.js.
How would I do that? I can have the file as either b64 ot canvas element, so i'm flexible here, as long as it's saved to file.
I'm open to other solutions too.

You can't save a file with client language only. You have to save it to a server, own server or external server or a service like AWS.
The best solution without server-side (strangly) is to use a API for save image and get link from this API. Then you can use this link to Outlook.
You can use https://aws.amazon.com/fr/cloudfront/ free for one year with 50Go and 2 millon request monthly.
If you do not exceed 300,000 images per year you can use this service : https://cloudinary.com/pricing
You can also use https://www.deviantart.com/developers/ but that's not really the point of service.
Weird solution :
Be careful, the login and password of your FTP user will be available in the source of your code. Minimum rights must be administered.
You can use this script for talk to FTP server from JS (not tested but seems worked) : http://www.petertorpey.com/files/ae/scripts/FTPConnection.jsx
You can try something like that :
var ftp = new FtpConnection("ftp://URL") ;
ftp.login("username", "password");
ftp.cd("FOLDER") // For move to folder
ftp.put(file,"FILE.PNG") ; // File must be a File JS Object
ftp.close() ;

post not finding php file on local server.

I'm trying to use an post call to a get some data from a php file. I know the code works because I'm using it on another computer and it works fine. Every time I make a call I get this error.
HTTP404: NOT FOUND - The server has not found anything matching the requested URI (Uniform Resource Identifier).
(XHR)POST - http://localhost/PhpProject4/‪newEmptyPHP.php
This is from MS edge. The php file is in the same directory as the html file and the file making the call. I think it has to do with my xampp server. Any Ideas? Also this is all on my local machine.

Just check your .htaccess file, maybe mod_rewrite changes adress

Questions about extract.autodesk.io - taking a file path instead of choosing with the file chooser

I'm trying to modify the project so I could plug in a file path or a file as a variable instead of the user choosing the model file. So I'm looking for where the actual upload happens.
In submitProject():
https://github.com/cyrillef/extract.autodesk.io/blob/master/www/js/app.js#L129
I see that it just sends (with an ajax request) an object that holds the file name and unique identifier but not the actual binary file.
In here:
https://github.com/cyrillef/extract.autodesk.io/blob/master/www/js/upload-flow.js#L34
there's r.upload(), is this the actual upload of the model?
Does it start to upload the file right as you press ok in the file chooser?
Is there a way to give it a file path to upload instead of uploading with the form and file chooser?

The author of this sample should be on Christmas vacation, I just downloaded and setup the extractor sample on my machine, with a little debug into the code, let me try to answer as much as I can.
In general, I think some of your understanding is correct, but let me explain a little more:
For a local file to be uploaded and translated, there are actually 2 steps of actual “upload”.
As you mentioned, when you press ok in the file chooser, yes, the file will be first uploaded to the "extractor" server as you noticed by some methods like r.upload(), it’s actually using a JavaScript library call “flow.js", which provides multiple simultaneous, stable, fault-tolerant and resumable/restartable file uploads via the HTML5 File API. I am not expert on this, but you can check that module about how to use it to upload a file.
By now, your file is uploaded from client to the "extractor" server, but if you want to translate the file to "svf", the file is required to be uploaded to Autodesk Server(OSS), that is done by clicking “submit my project” buton, when you click this button, as you mentioned, from client, it will call the method submitProject() in https://github.com/cyrillef/extract.autodesk.io/blob/master/www/js/app.js, this method will send a post request of “/api/projects” to the "extractor" server, if you check the code at server side https://github.com/cyrillef/extract.autodesk.io/blob/master/server/projects.js , you can see the extractor server actually upload the file to Autodesk OSS, and then triggers the translation service.

This feature (passing a URL string vs a file binary) is already implemented. You can use the uri: edit box and paste your file URL there. It supports http(s) or S3 uri with access token.
The physical upload happens in this file, whereas the SubmitProject() code sends only information as JSON. The JSON object only contains a reference to the file which was uploaded using flow.js. But would contain the uri string if you had choose that method.

I want to upload a file by ajax but I don't want the server direct link appears

Everyone know when upload a file by ajax we must add the direct link to the php file which will upload the file, ex: url: site.com/upload.php.
What I want is that this link site.com/upload.php will not be the direct link to upload the file, but it will be just redirection to the up.php file which will be upload the file actually.
The aim is I want to disappear the link which responsible for upload the client file.
Is this idea can be implemented ?

IMHO If your target with that is security, You're targeting the wrong phase.
Instead of protecting the PHP File location, you can protect the file itself.
the UP.PHP can have some "filename" protection using mod rewrite (How to remove .php or .html extension from single page?)
The UP.PHP can have authentication and authorization through your site auth/autho system, and if you want it public, do it keeping FORM ID pair or something.
The address of the UP.PHP will look something like: site.com/upload/receiver and will point to your file, if you want to protect even this address, you should use anything else but JS Ajax, like flash, java, or anything else.
Just follow any how to do it step-by-step.
https://www.google.com.br/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#safe=off&q=flash+file+uploader+example
Use SSL encryption...