Xamarin application access LAMP server on a Raspberry Pi - iphone

I'm currently making my first steps into developing a basic iPhone app and want it to retrieve information from a raspberry Pi set up as a server and send a push alert to the app user. The process should look something like this:
Daily list of Flavours added to Pi (which is set up as a server using LAMP)
iPhone app (designed/built using Xamarin) retrieves list of flavours from the server
Push notification sent based on user defined 'favourite flavours'
At this stage I'm trying to keep the app as simple as possible in that the users only need to select their favourite flavours from a full list and the app will retrieve and compare their list against the source list giving them a notification if any of their favourites are available.
I realise this is quite an open ended question. What I'm really looking for is any ideas if this process sounds feasible, possible flaws in my understanding, any interaction issues between the pi server the app and if people think that a Pi would be able to handle this functionality.

Related

Is a server required for push notifications?

Just to start I, I want to say I have read the this tutorial: http://www.raywenderlich.com/3443/apple-push-notification-services-tutorial-part-12
After reading it, had a few questions about push notifications... my main questions is, is a server required.
I have made an app that has informational content for my business... however every week/month or whenever I choose, I want to be able to push a message to all the user who have downloaded my app (every device would receive the same message).
Preferably, the way I would want to create and send the notifications... is through a separate app that I, the developer only has.
Now back to my question, would I need to get a server to do this?
There are a lot of free Push Notification servers - for example QuickBlox
You don't need any server code, QuickBlox already wrote all for you.
Just look at Push Notifications iOS sample - This sample enables you to send notifications and alerts to users at any time through an API or easy-to-use admin panel.
Just download it, move some code from it to your app - and enjoy it.
We use a framework called Parse that let's us send broadcast pushes to all users. You don't need to maintain a server (they do it for you). It's free for under 5 million queries a month.
No you dont need a server, you can simply create your own application that connects to the apple push notification server but you have to ensure you use the required develop/publish certificate for the ssl connection, you can see that on the tutorial you read in the "Making a PEM file" secction. He is connecting directly from his mac to the servers, it fails without the certificate but it doesnt with it.
See here:
As I’ve mentioned a few times before, you need to set up a server that
sends the push notifications to your app. For this first test, we’re
not going to set up a server just yet. Instead, I’ll give you a very
simple PHP script that sets up a connection to APNS and sends a push
notification to a device token that you specify. You can run this
straight from your Mac.
You can make your program set up a connection like that.

Messaging service within my app

I need to implement a message service into my app that works exactly like this:
users register with a nickname within the app
they can add contacts (just nicknames) and send them a message by just specifying their nickname
they can send a message whenever they want, and the message is stored on a server until when the receiver connects to internet.
when a message is received, a push notification is triggered.
So, the messages work pretty much like emails, however instead of using email addresses, we only use usernames. I'm also going to build my own back-end for it.
Which APIs should I use or which 3rd party framework can I use ?
And any tip ?
N.B. I need to make it work with iOS 3.0 as well.
and in the future I will develop an Android app, so the nicknames should be unique and I should be able to send messages from iPhone to Android devices within the same app.
thanks
I've successfully used the Three20 library and would recommend giving it a try. It's an open source spin-off originated by the author of the Facebook app. It features a bunch of additional GUI components that might be useful to your project, like a message composer that resembles the one used by Apple's email app.
Also, Three20 features a nice framework for handling navigation within your app. Currently, the biggest drawback seems to be that certain features don't play well with the iPad API.
The answer seems to be Push Notifications

Using Remote Notifications In My Application

I am currently starting my way on developing iPhone applications, and I have recently encountered a problem which I could not find a proper answer to.
In my application, I want one iPhone to send a request and another, far iPhone respond to that request using an Alert View, almost like the way Game Center works when you invite someone to play with you.
Do I do that with Push Notifications? Some server? Or what?
Thanks ahead,
A Newbie Developer.
Not the simplest things to try and do when you are new - but have a look at GameKit.
There is a sample application called GKTap which shows how to hook up two iPhones.
Don't be fooled by the word Game. This framework makes it easy to set up communication between phones, even using Bluetooth.
It depends on what you mean by "far". If you mean in another room, but within Bluetooth range or on the same local network, then there is GameKit. If you mean on a different network, or a long distance away, then you are looking at needing to have a server that keeps track of the devices and the connections between the devices so you can use Push Notifications. If you are thinking of something like Words With Friends where it sends a message to another user to tell them it is their go, then you would need the server.

How do I upload files using http/ftp to iphone/ipad? (Eg. ifile, goodreader)

Is there any good advice on uploading files to the device? I've seen many apps create a http server on 80 or 8080 to upload files. Does that mean I have to implement a server too?
Are there any 3rd-party libraries? (Preferably open-source and non-GPL)
EDIT: I am going to upgrade files in the app for specific devices in a corporate environment, so the ipad pulling files from a central server is also an alternative. But I would have to send messages to these ipads to tell them to fetch those files.
But I would have to send messages to
these ipads to tell them to fetch
those files.
Push Notification Programming Guide
Or mail with custom URL scheme for launching your application.
iOS Application Programming Guide - Implementing Custom URL Schemes
I assume what you want is a kind of automatic update. An app do something by order from server without user's manual operation.
I don't know enterprise-license specific feature of iOS. But I believe there's no such enterprise-specific APIs. And as I know, automatic update is almost impossible. Because,
There is no system-level support for automatic update. (yet?)
So messaging and fetching feature should be implemented in app.
But no app is guaranteed to run in background for long time.
And also user can turn off any app at any time.
There is no way to send message to an app which is not running.
Even you can send, there is no way to address each client form the server.
If your app is running, sending message or commanding them to fetch or do anything is just a simple work. The problem is there is no regular way to force them always keep alive. Even under situations like OS reboot or abnormal termination.
However there is an alternative. Just registering app as VOIP app like Skype. OS does not keep the app running too, but will monitor specific socket port, and will wake your app when the socket receives some message. For more details, see here: http://developer.apple.com/library/ios/documentation/iphone/conceptual/iphoneosprogrammingguide/BackgroundExecution/BackgroundExecution.html#//apple_ref/doc/uid/TP40007072-CH5-SW15
In AppStore, an app using VOIP for other purpose like automatic update will not be passed, but you have no need to concern about it.
And other way to send message to device without running app is push notification. This is a feature supported in system-level. But this is not designed to commanding app. This is designed to send textual message. So If your app is not running, the message will be displayed to user. However, you can guide the user to start the app by sending push notification.
As a final option, you can request some feature to Apple for enterprise environment. If your company is big enough to get an enterprise license, Apple will consider your feature request seriously.
If you decided to use VOIP method, I'm sorry I can't help you any more. I have no experience of implementing this kind of app. But it should not so hard.
However hard part is server. It definitely require custom server program which keeps TCP/IP connection. Regular HTTP server cannot be used. Because HTTP itself is designed as not to keep TCP/IP connection. You have to build this kind of server yourself from scratch. You'll have to handle lower level TCP/IP transmissions.
There are a few solutions(both of free/commercial) for this kind of server, but none of are popular because this kind of server regularly needs full customization. So there's nothing to re-use or share.
However I believe this is most suitable implementation for your app.
If you can satisfy automatic update only when the app is running, you can archive it by polling server status from the client periodically.
This is easy to implement because you can use regular HTTP servers for this. Client connect and download recent updates from central server periodically. If there is a new update, just fetch and do what you want. And the app is launched, just check the update at first. Prevent all operation until update applied.
This is regular way. Most of applications are built with this method. In this case, you have no need to implement server or hard thing.
However applying speed of update is depend on polling period.
(Edit)
I couldn't care about private APIs. Because your app is not for AppStore, so you can use private API's freely. (This is different thing with jail-breaking. There are so many hidden features by excluded from documentation) I don't know about private APIs, but it's possible there is some API which enable the support for keep-alive of the app.
However, this reverse engineering work is so painful unless you're born to hack.
You may try to use the following open-source in your project:
http://code.google.com/p/cocoahttpserver/
https://github.com/robin/cocoa-web-resource/wiki
Apple has some sample code on their website that details exactly what you're looking for:
http://developer.apple.com/library/mac/samplecode/CocoaHTTPServer/CocoaHTTPServer.zip
So you have a couple options:
You could distribute your app wirelessly within your organization and push new content out as app updates. Apple provides this option to their Enterprise Developers.
Wireless App Distribution
iPhone enables enterprises to securely host and wirelessly distribute in-house apps to employees over Wi-Fi and 3G. Apps can be updated without requiring users to connect to their computers. In-house apps can be hosted on any web server accessible to users. Users simply tap on a URL to install apps wirelessly without needing to connect to their computers.
The alternative is you configure the app to fetch the updated data. You describe adding an HTTP server to the iOS device, but there's no way the server can receive data when the app isn't running. Given your needs, it would probably work better to embed a web client in your app instead.
If I was in your shoes (and option #1 didn't work), I'd use ASIHTTPRequest to check with a server at launch/daily. If there are new updates, the app could then either prompt the user that there are new data files to download, or it could just silently download them in a background thread.
UPDATED: Perhaps I should have been more explicit about how to do #2. You can configure the download so it isn't interrupted when the user quits the app (you don't need to do a Voip hack). Check out the Completing a Finite Length Task in the Background section in the iOS Programming Guide.
There are http server sample codes from Apple and open source community such as cocoahttpserver TouchHTTPD.
You can upload file to the http server on iphone.
Here's a blog and screen-shots about running cocoahttpserver and upload file to iphone.
The Python CGIHTTPServer allows you to create a server in 0 lines of code:
jcomeau#intrepid:~/rentacoder/bin2txt$ python -m CGIHTTPServer
Serving HTTP on 0.0.0.0 port 8000 ...
Actually implementing a script to parse the input and save the file would take a little more effort.
[later]
OK, so forget about that, Apple doesn't allow it. See Local server on iPad for the iPad at least.

iPhone: Need suggestion for SYNC contact

i want to create a application which sync my iPhone contacts to my server and vice-versa.
i read a article on google Get Google Sync on your phone . i want to this type of feature which directly update the contact without user interaction (however one time setting is desired).
any body have idea how the google sync work .
Please advice me that how can i achieve this task. any suggestion and link is greatly appreciated
I think it's important to separate the two overlapping approaches in your question.
Firstly, Google Sync is essentially a way to use Microsoft Exchange protocols and to setup a Mail / Contact / Calendar profile on an iPhone. The iPhone OS supports this feature, not an iPhone App in the App Store. Google Sync leverages this fundamental capability of the phone by exposing the data (mail, contacts, calendars) via these known protocols. If you want to expose data in this way to your users, setup a Microsoft Exchange server and ask questions on serverfault.
Secondly, there are iPhone apps. iPhone apps sold in the app store are not currently allowed to run in the background. This means you can't emulate functionality like iTunes or Mail where your music plays while you are browsing the web, or mail checking is done while you are playing a game of Mini Squadron. If you want this backgrounding capability, file a bug/enhancement with Apple.. However, you can interact with iPhone contacts (Address Book) via the API.. You can also of course "re-invent the wheel" and expose the data however you like via the internet, and consume that data from a custom iPhone App with the one caveat that users would need to actively launch your application to get to this data and it would not be integrated with the built-in iPhone Calendar, Address Book or Mail applications. Some good examples of that are some of the music community apps that have messaging systems built into them. Presumably that is all being done with web services.
EDIT: It is also worth mentioning that should you go the "iPhone App" route, you should at least consider if push notifications are right for you, and if so how you will handle it.
Have you seen the API-Docs?
http://developer.apple.com/iphone/library/documentation/ContactData/Conceptual/AddressBookProgrammingGuideforiPhone/100-Introduction/Introduction.html
Next there is an application I use called Funambol - it is a sync4j Server/Client. They have an open source application to sync contacts on the iPhone. Source is somewhere in their repository, informations here: http://forge.ow2.org/scm/?group_id=96
As slf told you your application must run in foreground. This may limit you.
Good luck & best regards,
Florian
The 3.0 SDK will allow your application to read contact data on the phone.
Web services will allow you to publish that data to your server, and receive updates.
You may also want to use coredata to store a hash of all contact data so you can tell what is new / updated and just send that data to your server.