HTTPD Library - Capturing Form Data

[j9v6]

I've just discovered the HTTPD Library and using the sample code in the Dictionary I can start and stop an HTTP server on iOS and Android and connect to it via a computer on the LAN. (Huzzah!)

I then created a simple HTML page that displays a form. I would like to capture any data entered via the form and use it within my LiveCode mobile app. In the old CGI days I would use an action in the form tag to call a CGI script to process the data. Something like...

<form action="process_data.cgi" method="POST" enctype="multipart/form-data">

I'm assuming I can't use an action script here so without an action script is the form data returned via POST to the LiveCode app and if so how can I access it?

Thanks for any help.
Al.

[j9v6]

HTTP-Test.livecode.zip

sample httpd implementation

(1.75 KiB) Downloaded 212 times

To clarify my query, here's my LC file. [This is just running on a Mac for test (you don't need to build for iOS or Android)]

Open the HTTP-Test.livecode and run it. Then using a browser go to http://<the-IP-address-show>:12345. This will display something similar to:

MacOS
192.168.1.19
Choose file to upload
[Choose File]
[Submit]
pRequest[content]=
pRequest[headers][accept]=text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
pRequest[headers][accept-encoding]=gzip, deflate
pRequest[headers][accept-language]=en-gb
pRequest[headers][connection]=keep-alive
pRequest[headers][content-length]=44
pRequest[headers][content-type]=multipart/form-data; boundary=----WebKitFormBoundaryLycAxMOSgkyQXYaB
pRequest[headers][host]=192.168.1.19:12345
pRequest[headers][origin]=http://192.168.1.19:12345
pRequest[headers][referer]=http://192.168.1.19:12345/
pRequest[headers][upgrade-insecure-requests]=1
pRequest[headers][user-agent]=Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1.2 Safari/605.1.15
pRequest[method]=POST
pRequest[parameters]=
pRequest[port]=12345
pRequest[resource]=/

Click the Choose File button and find a .CSV file (that's what the app's looking for), then press Submit.

It appears there's no content being loaded as pRequest[content] remains empty.

However, if I add a text input field to the HTML (<input type="text" blah blah blah> ) and refresh the browser, I can type in some text and the pRequest[content] shows the text entered.

So it kinda works, but I'm trying to get a file to upload and access it.

In all probability I'm missing something obvious, but can't see it.

Anyone got any ideas?

Thnx, Al.

HTTP-Test.livecode.zip

sample httpd implementation

(1.75 KiB) Downloaded 212 times

[matthiasr]

You cannot use html to process the formdata. You would need PHP, Perl or LivecodeServer for example. But this is not possible with the HTTPD library.

[Bernard]

I've never looked at the httpd library, but in the Dictionary it talks about METHODS, but only specifies GET. Then the final bullet point says that for url-encoded forms the array[content] will be empty, which suggests POST is not fully implemented.

If running a httpd daemon on mobile is something you really want to do, it may well be possible to built more features into the httpd library. I'm guessing it is a minimal functionality built because that minimum was needed for a specific project. In the past I can think of a couple of people who built more full-featured httpd libraries than this appears to be.

Apart from running SSL sockets, Livecode has got socket support (as you will see if you dig into the httpd library).

[j9v6]

Yeah I spotted the bullet points, but as I was using an enctype of multipart/form-data instead of application/x-www-form-urlencoded I thought that POST would return the data. It may actually be returning data but it's not showing, so I'm going to investigate how to decode the pRequest[content] in case there is anything in there.

[FourthWorld]

Wyatt is the advantage of using an LC httpd over Apache?

[j9v6]

The LC httpd runs on iOS and Android and I need a small server in my app.

[FourthWorld]

Restricted to LAN-only?

[j9v6]

I believe thats the case for HTTPD Library.. and I only need it to support LAN access for my app.

[j9v6]

Hah! I think I've found the problem and why I'm getting no data returned.

In com.livecode.library.httpd there is a handler called ___ReadContinuedRequest that has some conditional logic for processing data with a "--todo" comment in the case condition for handling multipart/form-data

if sRequests[pSocketID]["content"] is empty then
set the itemDelimiter to ";"
switch item 1 of sRequests[pSocketID]["headers"]["Content-Type"]
case "application/x-www-form-urlencoded"
put __ParamsToArray(word 1 to -1 of pData) into sRequests[pSocketID]["parameters"]
break
case "multipart/form-data"
-- todo
default
put pData into sRequests[pSocketID]["content"]
end switch
end if

Open to suggestions as to how to handle the pData and format it for insertion into sRequests[pSocketID]["content"]

[FourthWorld]

I'm not clear on the setup. It sounds like you have some phones on a LAN from which you'd like to send files to another phone which is always on acting as a server - is that correct?

[j9v6]

The setup:

An iOS or Android phone connected via WiFi to the LAN.
A computer connected to the LAN
The iOS or Android phone will run an HTTP server (HTTPD Library)

The objective:

Using the computer, connect to the HTTP server running on the phone and upload a file to it.

This should be simple enough if the multipart/form-data gets processed. Currently the HTTPD Library has a "case" construct defined for multipart/form-data but the construct does not contain any code. Instead it has a comment saying "--todo".

Current situation:

I'm stuck!

[SoapDog]

This should be simple enough if the multipart/form-data gets processed. Currently the HTTPD Library has a "case" construct defined for multipart/form-data but the construct does not contain any code. Instead it has a comment saying "--todo".

If you're in control of the form, you can use JS to change to make a POST request with the values in a JSON instead, I believe that should work even though I haven't tried. You would need to change the content type to "application/json" on the request, and decode the JSON yourself on your callback handler in your stack. It should be inside pRequestA["content"], if I understood the library correctly.

[FourthWorld]

LC's httpd lib handles POST?

[j9v6]

Yes it does. Just not very well by the look of it.