I've written a socket server using Node.JS which works pretty well, but I'd rather use GAE for live production so that I get the warm fuzzy Google feeling.
On the client side, I'm using Flash->AIR (Desktop, iOS, and Android).
Question is, it seems that GAE does not support inbound sockets exactly. For Go, There's the Channel API and the XMPP API.
Channel API: Only works with Javascript clients, not Actionscript.
XMPP API: It seems that the most up to date Actionscript API out there is from XIFF... documentation is sparse, website is convoluted, and all-in-all it does not inspire trust at the level I'm looking for. On top of this, I simply want a socket server to pass basic messages back and forth, with an understanding of "users" and "channels". XMPP seems to be quite a lot more than that, and therefore more moving parts that can go wrong.
What is the standard answer to someone who's looking to build a custom socket server using a service like GAE, and not using Javascript clients? Just use XMPP and pray, or some other angle here I'm not seeing?
Related
Is there a way to stream a video and audio on a website just to the clients, using a camera installed on the server - for instance, like youtube does ?
I've started reading webrtc, but if I use webrtc I should create a stun/turn server and other things, which for one way stream I think is not necessary (this is just my understanding of the things..) because I don't need anything from the clients, literally, neither their video, or audio..
So is there a way to achieve this using html5, streaming just in one direction:
server (camera) -> clients
Is there something about this out there, or should I stick with webrtc ?
I'm going to explain a possible solution for this scenario, there might be others, but I hope mine gives you a rough idea of how you could do it and a start point to explore more about the amazing possibilities of WebRTC. Please let me know if something is not understood.
So, WebRTC is a free, open project that provides browsers and mobile applications with Real-Time Communications (RTC) capabilities via simple APIs. Sweet, that is: WebRTC has a quite good browser support (not in every browser though, Safari just started supporting it a month ago with Safari 11). But in this case we want to use WebRTC in the server side. At the end of the day we can still think about peer-to-peer real time communication, where one of our peers is the server.
I don't know if you are familiar with Node.js, but I recommend you to write your Server app with it (<3 Javascript!):
There are a few libraries that wrap WebRTC functionality to be used in the server side, like node-webrtc and node-rtc-peer-connection.
But I recommend you to to take a look at electron-werbrtc, since
the others might be using deprecated methods or be incomplete.
electron-webrtc runs a headless Electron client in the background to
use Chromium's built-in WebRTC implementation. So with it you should
be able to access the Camera in your server and create a stream to be
served to the other peer (the browser).
All above would be the WebRTC related tasks, in this case: streaming video peer(server)-to-peer(browser).
Now, let's talk about signaling process, stun and turn.
Signaling: imagine now a scenario peer-to-peer with 2 browsers, they want to establish a direct connection and stream video and audio between each other. But they don't know each other, like if I don't know your home address, I can't send you a letter. So they need a service that helps them know each other, so they can have the other's IP. This should be done by what is called "a signaling server". If somehow you know the other peer IP, you wouldn't need a signaling server.
STUN/TURN: the scheme above works perfectly in a local area network where each peer has its own IP address and there are no firewalls and routers between them. But otherwise, you can have peers behind a NAT or firewalls, and then your signaling server won't be able to make both peers to discover themselves. If you have peers behind a NAT, you'll need a STUN server, and if you have peers behind firewalls you'll need a TURN server. This is a bit simplified, but I just want you to have the general picture of when you might need STUN/TURN servers.
To better understand Signaling, STUN and TURN, there is a very graphic article that explains them perfectly.
Now, for your scenario:
I think you prob don't need STUN/TURN servers and also you prob don't need to implement the signaling process, because the browsers that are supposed to receive the stream from the server will know that server address, right? So they can establish a WebRTC connection with it.
EDIT: it is likely that you will need to implement some sort of handshake between the server and the clients (browsers), so this will be the signaling process. This is not part of WebRTC and this is why you need to implement it yourself. As I said, it is the way 2 peers can discover each other, but they also exchange information as their local media conditions, like codecs, resolutions they can handle, etc. For your case, your signaling server could be hosted in the same server you use to strea: you can build a small node.js app that runs there and that manages all the signaling process easily, it is not a big deal. I recommend you to read this article, and specially the section "How can I build a signaling service?". In general all WebRTC articles from that site are very helpful.
Does this make sense to you? I think with it you can start digging a little bit more and see if with this is enough or you need to implement more stuff. Hope it helps!
I'm trying to build my first Sproutcore App and I struggle to connect it to a MySQL-Database or any datasource other than fixture. I can't seem to find ANY tutorial except this one from 2009 which is marked as deprecated: http://wiki.sproutcore.com/w/page/12413058/Todos%2007-Hooking%20Up%20to%20the%20Backend .
Do people usually not connect SC-Apps to a Database? If they do so, how do they find out how to? Or does the above mentioned tutorial still work? A lot of gem-commands in the introduction seems to already differ from the official Sproutcore getting-started-guide.
SproutCore apps, as client-side "in-browser" apps, cannot connect directly to a MySQL or any other non-browser database. The application itself runs only within the user's browser (it's just HTML, CSS & JavaScript once built and deployed) and typically accesses any external data via XHR requests to an API or APIs. Therefore, you will need to create a service wrapper around your MySQL database in order for your client-side app to be able to load and update data.
There are two things worth mentioning. The first is that since the SproutCore app contains all of your user interface and a great deal of business logic, your API can be quite simple and should only return raw data (such as JSON). The second is that, I should mention that the client-server design, while more tedious to implement, is absolutely necessary in practice, because you can never trust the client side code, which is in the hands of a possibly nefarious user. Therefore, your API should also act as the final gatekeeper to validate all requests from the client.
This tutorial I found helped me a lot. Its very brief and demonstrates how to implement a very simple login-app, how to send post-requests (triggered by the login-button-action) to the backend-server and how to asynchronously process the response inside the Sproutcore-App:
http://hawkins.io/2011/04/sproutcore_login_tutorial/
I recently installed varnish on my servers in order to ease the workload a bit. However one of my websites extensively uses the HTML5 'navigator.geolocation.getCurrentPosition()' function and also falls back on the maxmind database installed into nginx when the aforementioned is not available.
I can understand why the nginx/maxmind version won't work as it relies on the nginx server knowing what IP you are from, and as varnish is sitting in front, requests may not even get as far as nginx.
However, why is the HTML5 geolocation function not working? I assumed this was purely client side and should be unaffected by the web server?
In order to get the Nginx Http GeoIP module working behind a proxy, you will need to pass the IP address of your proxy server to the geoip_proxy directive.
I don't know if we have enough information to speculate about why the W3C Geolocation function is not working. As you suggest, there is no obvious reason why it should not work when your site is behind a proxy server.
As an aside, you might want to check out MaxMind's GeoIP2 JavaScript service, which tries to use W3C Geolocation and then falls back on the web service if that is not available. MaxMind provides a free option that might meet your needs.
I'm attempting to make a mail client that is HTML5/JS only where users would have to define their mail server and credentials.
I've surfed google leading to dead ends and figured that this is the next best place (or superuser.com).
I was thinking of using HTML5 WebSocket if I could to make the connection to the server but I don't know enough of smtp, imap, or pop3's architecture to understand how javascript could pass the args and perform what I want it to do.
PHP cannot be involved in this project otherwise I wouldn't be asking the question.
Any help in locating this would be fantastic.
Nothing is impossible. Except this.
In standard HTML or JavaScript, you can't make raw-socket connections, which is what you'd need to speak any of the protocols you've listed. The WebSocket API doesn't help you, because the server must also speak WebSockets, and mail servers don't. This is actually all a good thing, though. Imagine if you visited a random website and it telnetted to your home router, setting it on fire and burning down your house. That's what websites would be able to do if they could initiate plain TCP socket connections.
You have a few options I can think of, neither of which involves building a webpage. (And to be clear, you didn't say your project had to be a webpage; you merely said HTML/JS, so these are indeed legitimate options.)
First is something like node-webkit. As the readme says, "You can write native apps in HTML and Javascript with node-webkit." You'll still have to distribute it as a native app, because that's what it is.
Second is a Chrome app, specifically using the chrome.socket API. But have fun writing a TLS layer over those sockets, which you'll find is a requirement for almost any mail server these days. If you succeed in doing that, you'll be able to distribute your mail client in the Chrome Web Store, where I assure you an email client will be quite popular.
Third, write a webserver that operates locally, so your users will visit something like http://localhost:9999/mail in their browser. This will be a real pain to distribute, but you can use almost any technology you want.
I'm sure there's a fourth valid option, and someone else can chime in on that one.
Best of luck.
Can anyone give me a brief rundown of how Facebook and Google Talk work, are there persistent connections involved similar to the classic Java based chat systems whereby a server manages the connections and directs messages to the necessary destination or are they stateless? I'd like to create something similar to these but I'm not sure where to start and if I need to have custom services running on a server I may have to rethink my approach.
I'm not after a full-blown explanation but I am interested to know if there's a stateless approach that doesn't require services running on a server. If Html5 is required that's ok.
Both use the Jabber protocol: http://www.jabber.org/