I'd like to know if my idea is even possible, but based on everything I've searched for so far, it seems like it's not possible. I would love to hear what the experts think.
Goal: Interface with laboratory equipment via TCP/IP sockets using HTML/Javascript.
One problem is that I have no control to program the server. Therefore, I can't use HTML5 websockets. The vendor has not implemented websockets. The equipment server waits for a socket connection, and then communicates via API.
Because HTML5 and Javascript are relatively OS-independent and are 'built' for user display, I'd like to create a browser-based program. I've found related questions and answers on SO, but they are older now, so I'm wondering what is the current technology.
Thanks in advance, and please let me know if you have any questions.
The W3C published a first draft for a 'Raw Socket' standard:
http://www.w3.org/TR/raw-sockets/
I think this might be what you're looking for, but I wouldn't count on it being implemented by vendors in the near future, since it's only a first draft.
Another thing I found out while searching, is that chrome apparently enables tcp/ip communications in extensions (did not check this myself, so can't gurantee):
http://developer.chrome.com/apps/app_network.html
If possible, you might consider writing a chrome extension (though it's not really "HTML5").
I read this as needing essentially a telnet session to your equipment.
Currently, there's no way to do this from the browser without a plugin.
This question has some similar discussion: Best way to display high-speed data from a telnet interface on a web view?
Why not use the server where the HTML5/Javascript code is created. To create to connection to the device and convert this to something you can use, like websockets.
Related
I want to identify a user by unique machine id across all browsers. So came up with an idea of launching a app which determines the machine-id (like electron using nodejs) and passes back the info to the browser that launched it and use for identifying the user.
I have seen something like this been done on canyourunit
Can anyone point me right direction where can i find some info about this kind of approach.
As you would be asking a user to download and execute native code, electron or whatever else, there are several complicated issues to consider.
The obvious first one is that you must consider the user platform (OSX, Windows, Linux...) then, communicating back with the browser directly (which one?) is probably not practical.
Your native application could however send the machine id/fingerprint to your backend so you could identify what web client is what.
This is quite involved, fragile, and even if you only support Windows, will fail in many scenarios (system policies, firewalls, antivirus, proxies, strange network setups...)
All in all, it would seem that you should consider more standard Device fingerprinting techniques if you only need an ID.
My team has been using the Web Audio API/Getusermedia in a product and we are going really well with our chrome and firefox users. But we still have a large base of users that we would love to reach, but due to technology barriers, we still can't (mostly, those are IE users), as their main browser does not support the technology, and they do not or can not change to a modern browser.
We are planning to get to those users, but we don't want to go to Flash, Flex, Silverlight or anything similar.
So, thinking about solutions, I thought that maybe I could pass by this difficulty if I moved the audio manipulation, from the browser to the server. NodeJS was the first answer when trying to figure out how to do it.
Would it be possible to be done using NodeJS? Are there any libraries available that would help us accomplish this? Are there any other technologies that would allow me to do this?
Thanks anyone that could help.
It could easily be done. Node is simply an IO engine designed for rapid response. If it needs to happen in real time then I imagine latency would be a usability-breaking issue due to networking restraints. If it doesn't, then I think it would be a great solution! :)
Either way here are a couple related resources
https://www.npmjs.org/package/webrtc.io <- latency optimization library intended for work with media streams
http://wac.ircam.fr/ an upcoming conference (Jan 2015) dedicated to the types of problems you are dealing with.
http://www.sitepoint.com/5-libraries-html5-audio-api/ A few web libraries for use with audio. #3 and #4 look like they are related to what you are trying to do
You can try using this (is in development):
Node Web Audio API
https://github.com/sebpiq/node-web-audio-api
Installation
npm install web-audio-api
Demo
node test/manual-testing/AudioContext-sound-output.js
I'm working on HTML5 app that lets several users to work on one document. I need to add a possibility for users (editing the same document) to talk to each other. And I just don't know how to start with that. Here are my questions
Is there an HTML5 lib allowing to transfer sound from microphone between clients?
What about streaming video from camera?
What is an easiest server-side solution for that?
Any thoughts are strongly appreciated! So don't be shy! :)
UPD: please note that I need an abbility for more then two users to talk.
For this you can use WebRTC.
However, this is a very young and unfinished technology that as already stated is currently available only in Chrome stable and Firefox beta. This means there will probably come changes to the current spec, something to be aware of in case of early implementation. But it allow you to use video and audio communication directly in the browser.
Quick-start here:
http://www.html5rocks.com/en/tutorials/webrtc/basics/
Other options are Flash based plugins such as flash-videoio. This is an open source plugin but will naturally require Adobe Flash installed. This may or may not be a problem depending on the company's security policy.
For technical details on implementation please see examples on the provided links.
For many-to-many you can use either:
"Mesh" - everybody connects to everybody. This however is costly on CPU and mobiles are often left out.
"Star" - everybody goes through the most capable device. However, with many connections this will soon run slow for the device handling all connections.
MCU. Specialized server to handle all connections. If mixes audio and video and handles drop-outs as well without affecting the other callers.
Examples of MCU's:
http://sourceforge.net/projects/mcumediaserver/ (open source)
http://www.medooze.com/products/mcu.aspx (commercial)
you are searching for navigator.getUserMedia()
that allows the various users to share video audio and data.
the support is very low... only chrome and the latest verions of opera and firefox support it.
and totally no support on mobile devices... maybe in the next android chrome... dunno
as there is much to talk about and i have no clue on how u wanna setup everything i suggest u read a little more about that on the urls...
http://caniuse.com/stream
http://www.html5rocks.com/en/tutorials/getusermedia/intro/
http://dev.w3.org/2011/webrtc/editor/getusermedia.html
https://developer.mozilla.org/en-US/docs/WebRTC/navigator.getUserMedia
http://my.opera.com/core/blog/2011/03/23/webcam-orientation-preview
http://simpl.info/getusermedia/
and SERVERSIDE solution nahh... thats not a good solution
clientside is the way to go.
Not sure if you're required to do it yourself from scratch or are able to use third party libraries/tools.
In which case I would recommend using Tokbox which has support for WebRTC and SDK for iOS.
Their API is simple and easy to use.
Is it possible to access a smartcard reader connected to a computer from a web browser running on the same machine, i.e. from an ActionScript, JavaScript or whatsoever script running therein?
For example, I read something about the flash.external.ExternalInterface class in ActionScript. Can it be used for accessing a smartcard reader or is the Sandbox impenetrable?
Q: is it possible to access smartcard reader connected to a computer from a web browser running on the same machine?
A: Yes, it is possible. I was able to do that by using a signed JAVA applet. The java applet needs to be signed since it will require user to grant permission to access system files/hardware(same as letting an applet write/edit/delete a text file for you).
Why java? the smart card reader I used already has a JAVA API, it also have examples on accessing it using java. But the examples are coded in swing. (like a standalone desktop application) What I did is simply porting the java swing code to applet on a browser. I successfully used this applet to make a login and log out on a website/webapp by requiring smart cards, username and password. Pretty secure I would say.
The source code? As much as I would like to share it, but I'm bound on a company contract to not share the code. Just find a sample smart card access using java and just port it to applet(for web)
I hope this helps
You can also have a look at this beta native plugin:
https://github.com/ubinity/webpcsc-firebreath
It is cross-browser/cross-pltaform plugin based on firebreath framework, exposing a subset of the PCSC API.
When this proposal "Smart cards in browsers" gets implemented, we will also be able to use JavaScript for this.
I worked on doing the same circa 2012, back then, I worked on top of a previous work that provided a Java Applet.
Nowadays [December 2015], It makes even less sense to use a Java Applet due to 'recent' security problems, and following dismissal of support for Java Applets, and the native plugin technologies are also being discontinued as well.
Regardless of the current usefulness of a Java Applet, picking up on #Glen Allen's answer, I'm not bound by contract, and here is the open source code of an example Applet:
https://github.com/ist-dsi/signature
It was built upon a thesis work and it produces documents in this format: http://www.w3.org/TR/xmldsig-core/ more info on the why's can be found in the abstract of that MsC thesis https://fenix.tecnico.ulisboa.pt/downloadFile/395139415358/resumo.pdf (the author is a better engineer than thesis writer though, but it might be a good point to start if you want to know the state of the art of the thing, although is old)
There are more requirements that on hindsight and without knowing made some odd choices of technologies on the code that I give you here, just disregard that part :)
One of the answers here hinted on PKCS_11 and open standards. Maybe the trick resides in a smart card reader driver that automatically sets up the certificate infrastructure on the client side, I remember having to go through lots of hoops though to setup my ID card's smart card with a reader on Mac OS X with Chrome [AFAIK it wasn't easy to set up the smart card reader with Apple's keystore, and perhaps also not that easy back then to have Chrome configured so that it would use client authentication and requested access to Apple's keystore].
Or maybe the NFC + SmartCard and a mobile app will be the way to go.
It just is such a waste to have whole countries with IDs with SmartCards, lots of government services already with webapps, and no easy way to connect the two.
Cheers.
You can use a signed Java applet to access the reader. Signed applets are allowed to access hardware peripherials, the smartcard reader can be accessed via the Java Crypto API.
Hope this helps.
If you can access the smartcard on your file system, like when a USB drive is connected and appears as a separate disk, then you can simply use flash.net.FileReference.
You can't achieve this with ActionScript/Flash if you've to stick to the browser.
Adobe AIR could do this, but then you'd have to build an application which the user has to install prior to using it.
Something like this (AIR):
http://cookbooks.adobe.com/post_Mass_Storage_Device_Detection_AIR_2_0-16747.html
Please forgive a question that has been addressed in some form or fashion previously. I have numerous test applications that run on various platforms from Windows 95, Windows XP, SUSE, RedHat, and other forms of *NIX. Currently, the mechanism has a native application that queries a database for some information then launches the test application to perform the test. This said program is a "launcher application" which I am trying to convert to a "HTML/Javascript Launcher Application". In addition, this "launcher application" needs to known when the test application is completed, then collect the test result then store the results in a database.
I have read that launching an application (executable) from HTML is not permitted, but this is entirely true in the sense (if I understand correctly). From what I have read here on SO and other sites, I have the following possible solutions:
Registering a unique protocol to an test application (SO Link)
Using Java to launch the application
Adobe AIR or its opensource counter part, Titanium by Appcelerator
Using WSH, though this will only work on Windows platforms
What would be a good (or best ) approach to solution this problem? Ideally, I would like to just use HTML and Javascript, but this may not be possible? Thanks for any advice and any example/sample code would be greatly appreciated.
Mark
Hopefully many people will think, as I do, that this is a 'bad idea'™, simply because in order for it to work you must allow your browser to launch software, which would be a huge hole in security, allowing access for all sorts of nasties.
Given you are cross platform I'd suggest you stick with a dedicated laucher application, but code it in java. This is the most common solution used in the java applications world which regularly crosses os's.
You could give JNLP (java network launch protocol) a try... Really easy to distribute and deploy full fledged applications in a platform independent manner. More or less through the browser if you like...