Background
My client's iOS application makes use of a third party library for advertising. About once a week we'll find that enormous numbers of our users are experiencing a crash because of some specific advert the API is presenting. When this happens our current reaction is to turn off all adverts until it is resolved.
We'd like to have some kind of per advert control.
Doing it properly
Ideally the third party library would provide an ID for the advert it's about to display and give the App an opportunity to block that particular advert. We'd log this ID and if it correlates with crashes (which is usually very obvious), block it.
However, getting the ID tracking in will require negotiation between my client's departments, and the the advert provider's departments, which will take some time, if it happens at all.
The work around
As an alternative, I'm wondering if there is a way that our app could intercept (and then potentially block) the network traffic of the third party library? Essentially run a transparent proxy that vets network traffic for our whole process (within which the library is running).
Are there hooks in iOS that would support this?
Just knowing the url requests would be a good start, this could at least be logged to help us isolate the advert and request it's not sent any more.
I'm not after a complete solution: pointers to useful areas in the API would be fantastic.
Any example code of something similar?
Other ideas for other ways to achieve the same result?
Related
In a World of Warcraft Vanilla Lua Addon Development, how can I issue an HTTP call to receive data back? If not, how can I get data from a web source into the game while playing?
I have a feeling the answer is tragically short, but would like the question asked and answered on Stack Overflow. My research came up lacking, and I recall doing some LUA in ~2007 and was disappointed.
Well, tragically short is an understatement. You simply can't. There was never any APIs that interacted directly with connections, let alone create any, let alone to arbitrary URLs.
Most of them just broadcast game events that occur from the game's connection, and the closest thing you can get to a "data stream" is add-on chat channels. But since bots violate the ToS, you wouldn't be able to make an account that responds to your addon's inquiries.
The closest thing you can get is building an "asynchronous mesh network", but that's only good if your addon has a considerable user base, and it's not guaranteed you'll get information timely.
The general idea is that your addon will have a public key (as in encryption), and you (only you) will detain a private key. Your addon emits a message to any connected peers, which store it on cross-realm SavedVariables, and you hope that someone will have characters on more than one realm. Upon login, the client addon will broadcast its latest packet (still encrypted) to that realm's addon channel, and hopefully within a week or so you might get the updated information across all clients.
A disadvantage is that you'll only get "push" notifications, the client won't be able to send any data back to you*.
That, or you could release a patch for the addon on Curse :P
BUT WAIT!
You mention vanilla, so I can presume you're developing this for a private server. Private servers often have one or a very small amount of realms, making the above mesh network much simpler. Instead of a mesh, just have encryption and manually login&broadcast on each realm every time you want to update the information retrieved.
Plus, you might even be able to contact the server devs to allow you an API that sends messages to the appropriate ingame addon channel (you'd have to ask).
Of course, if you pretend to make your addon server-agnostic, instead of tailored to a specific server, you're back to square one.
* Unless you are really dedicated to make that happen, because it's a ton of work.
There is no web API in vanilla WoW. There is a web browser widget in the game currently though, albeit very limited in usage.
If you have access to the server software code, you may be able to hook listening on specific game channels for user messages in a defined format, and let the server respond in a way for the addon to parse it.
This is for a visualisation project on what data gets recorded about us from our phones.
The idea would be to log as much detail as is reasonable to an internal location (probably) on the phone for later analysis, e.g. HTTP requests. It doesn’t need to be secret at all – the subject will be aware they are participating – and it doesn’t have to be 100% automatic; if the phone owner needs to perform some action regularly that’s okay too, although they need to be able to use their phone approximately normally throughout the day.
I can’t find any Apple APIs that look suitable, but that’s hardly surprising. I can find some approaches that would potentially work on OSX (tcpdump, netstat), so perhaps a jailbroken iOS device would support one of those?
Alternatively, running a custom proxy server would open up a bunch more options, but is there any way to get a mobile device to reliably route through a proxy server?
It appears this question provides a viable proxy-server-based approach:
https://apple.stackexchange.com/questions/81102/proxy-settings-for-iphone-3g-connection
Basically, it seems it is possible to route all requests through a proxy server, even over cellular.
I am trying to build an offline synchronization capability into my iOS App and would like to get some feedback/advice from the community on the strategy and best practice to be followed to do the same. The app details are as follows:
The app shows a digital catalog to users and allows them to perform actions like creating and placing orders, among others.
Currently the app only works when online, and we have APIs for all actions like viewing the catalog, creating/placing orders which return JSON data.
We would like to provide offline/synchronization capability to users, through which users can view the catalog and create/place orders while offline, and when they come online the order details will be synchronized and updated to our server.
We would also like to pull the latest data from the server, and have the app keep itself up to date in case of catalog changes or order changes that happened at the Server while the app was offline.
Can you guys help me to come with the best design and approach for handling this kind of functionality?
I have done something similar just in the beginning of this year. After I read about NSOperationQueue and NSOperation I did a straight forward approach:
Whenever an object is changed/added/... in my local database, I add a new "sync"-operation to the queue and I do not care about, if the app is online or offline (I added a reachability observer which either suspended the queue or takes it back working; of course, I do re-queueing if an error occurs (lost network during sync)). The operation itself reads/writes the database and does the networking stuff. My ViewController use a NSFetchedResultsController (with delegate=self) to get callbacks on changes. In some cases I needed some extra local data (it is about counting objects), where I have used NSManagedObjectContextObjectsDidChangeNotification.
Furthermore, I have used Multi-Context CoreData which sounded quite reasonable to use (I have only two contexts).
To get notified about changes from your server, I believe that iOS 7 has something new for you.
On the server side, you should read a little for the actual approach you want to go for: i.e. Data Synchronization by Dan Grover or Developing Android REST Client Applications (of course there are many more good articles out there).
Caution: you might be disappointed when you expect an easy solution. Your requirement is not unusual, but the solution might become more complex than you expect - depending on the "business rules" and other reasonable requirements. If you intelligently restrict your requirements you may find a solution which you can implement yourself, otherwise you may also consider to use a commercial product.
I could imagine, that if you design the business logic such that it takes an offline state into account and exposes this explicitly in the business logic, you may find a solution which you can implement yourself with moderate effort. What I mean by this is for example, when a user creates an order, it is initially in "not committed" stated. The order will only be committed when there is access to the server and if the server gives the "OK" that this order can actually be placed by this user. The server may also deny the order, sending corresponding messages to the user.
There are probably quite a few subtle issues that may arise due to the requirement of eventual consistency.
See also this question which contains pointers to solutions from commercial products, and if you visit their web sites give valuable information about the complexity of the problem and how this can be solved.
I'm making a program for IOS for the first time. I never had a iPhone so I don't really get how it works...
I want to make my system able to call a webservice on the background and depending in the answer show a notification.
How can I do this?
I read on the Internet that I can push notifications to the phone, however that won't solve my problem because I want my server to track the user position, so it need the user to silently tell the server it's gps coordinates.
Thank you,
GustDD
I will suggest building the app first to run in the foreground. I will assume you already understand how to use the GPS, so will not go into detail on that.
First off, you will need to write the server backend and app pretty much simultaneously. There are many choices for writing the server backend language wise. I prefer python, others ruby on rails. You want to build a REST API for the server that the iDevice can talk to with simple HTTP protocol.
You must decide on the API. You must think about what kind of data you will want to send and receive and how you will wrap the data. Also what HTTP protocols will you be using for specific requests, like GET POST etc. Furthermore, you will have to decide at what URL's on the server will it be useful to GET or POST to depending on the data you want to send or receive. I would suggest you use JSON to wrap your data. It is quite intuitive and easy to encode and decode.
Next you will have to decide how to talk to the server in iOS. There are many great third party libraries that dress up NSURLConnection or you can use NSURLConnection itself (sometimes a bit tedious). I personally like to use AFNetworking. It will do the JSON decoding and encoding for you which is a big bonus.
Finally, once you have the two communicating with how you want and with the data you want, now time to dress it up. You can allow your app to run in the background and collect GPS data and send it. You can also use the notification center to display information it gets from the server in the background.
Update to Comment
This will be extremely helpful for you with background programming. From an Android perspective, iOS is a little bit different since there is not really a direct correlation for Android services in iOS. Every little detail to put your project together is in that link.
We have a requirement from a customer to provide a "lite" version for dial-up and all the bells-and-whistles for a broadband user.
The solution will use Flex / Flash / Java EJB and some jsp.
Is there a way for the web server to distinguish between the two?
You don't care about the user's connection type, you care about the download speed.
Have a tiny flash app that downloads the rest the of the flash, and times how long it takes. Or an HTML page that times how long an Ajax download takes.
If the download of the rich-featured app takes too long, have the initially downloaded stub page/flash redirect to the slow download page (or download the bare-bones flash app, or whatever).
The simplest and most reliable mechanism is probably to get the user to select their connection type from a drop down. Simple, I know, but it may save you a world of grief!
There's no way to distinguish between a broadband or dial-up as a connection type, but you can make an educated guess by connection speed.
Gmail does this and provides a link to a basic HTML version of their service if they detect it.
(source: nirmaltv.com)
My guess is that there is some client side javascript polling done on AJAX requests. If the turnaround time surpasses a threshold, the option to switch to "lite" appears.
The best part about this option is that you allow the user to choose if they want to use the lite version instead of forcing them.
Here's a short code snippet from a code who attempted something similar. It's in C#, but it's pretty short and it's just the concept that's of interest.
Determine the Connection Speed of your client
Of course, they could be a temporary speed problem that has nothing to do with the user's connection at the time you test, etc, etc.
I had a similar problem a couple of years ago and just let the user choose between the hi and lo bandwidth sites. The very first thing I loaded on the page was this option, so they could move on quickly.
I think the typical approach to this is just to ask the user. If you don't feel confidant that your users will provide an accurate answer, I suspect you'll have to write an application that runs a speed test on the client. Typically these record how long it takes the client to receive x number of bytes, and use that to determine bandwidth.
Actionscript 3 has a library to help you with this task, but I believe it requires you to deploy your flex/flash app on Flash Media Server. See ActionScript 3.0 native bandwidth detection for details.
#Apphacker (I'd comment instead of answering if I had enough reputation...):
Can't guarantee the reverse, either--I have Earthlink dial-up, soon to upgrade to Earthlink DSL (it's what's available here...).
You could check their IP and see if it resolves to/is assigned to a dial up provider, such as AOL, Earthlink, NetZero. Wouldn't guarantee that those that don't resolve to such a provider are broadband users.
you could ...
ask the user
perform a speed test and ask the user if the result you found is correct
perform a speed test and hope that the result found is correct
I think a speed test should be enough.
If you only have a small well known user group it is sometimes possible to determine the connection speed by the ip. (Some providers assign different subnets to dial-up/broadband connections)