Xamarin.Forms and azure mobile apps with existing sql database - asp.net-mvc

I have an MVC application in production, hosted on Azure. Now I would like to develop Mobile app using Xamarin.Forms and Azure Mobile apps. The goal is to use the same database on both mobile and web. After reading available documentation online, I haven't found the way that would suffice my needs. I would like to know what is the fastest and best way to achieve that.
Is it enough to add necessary fields to existing entities that I would use in my mobile apps? Meaning adding fields like: Version, CreatedAt, UpdatedAt, Deleted and add another Id field of type string ex. MobileId (because current database uses autoincrement ids of type integer). Is this approach Ok, or should I do it some other way?
Any suggestion/advice would be much appreciated.

Azure Mobile apps is an accelerator and a way for devs not familiar with backend development to quickly create a backend for mobile apps. Since you already have a backend, you can simply add API methods in your MVC app that your mobile app will call. You will not benefit from some of the features that the SDK provides but you won't have to change your database structure.

You don't need to create a backend mobile app and in most cases you probably shouldn't. Is your app hosted in app services? If so there really wouldn't be any major differences between leveraging (and expanding as needed) the controller layer of your application. In most cases the datastore won't need to change to accommodate a mobile app vs a web app. Usually you want the datastore to change and evolve based on the features that you want your application to support as opposed to the plataforms that are consuming those features. It's usually a good idea to add an abstraction layer(s) to shield the datastore from platform specific requirements.
That being said there are a few Azure services that you should consider adding to make your life easier when developing Xamarin apps:
Notification Hub (provides an abstraction layer over the platform specific push notification services for ios and android).
App center (provides very useful telemetry data about crashes and errors that occur in your Xamarin clients).
App insights, it provides really good additional telemetry data with very powerful out-of-the-box visualization and querying capabilities for both web apps and mobile apps (I would configure app center to feed its telemetry data to App Insights).
If you provide me with more details about the application I would be happy to give you more detailed suggestions but the recommendations above serve as a good starting point for almost all the mobile application projects that I have encountered.

Related

CloudKit as a CMS using a regular web host, not sure where to begin? Is it possible?

CloudKit JS looks interesting. Yes, I know all about Parse, but was wondering if we can build a simple CMS on my server that can use the new CloudKit JS features: Authenticate, Add, Delete, etc. Or can this only run as a CMS in an App environment (like on an iPad)? AKA, the Public Container?
Basically what I'm trying to do is have my clients populate the App with data using CloudKit JS (using a simple web form front end), and not have to resort to using a php/mysql setup?
Question: Can CloudKit function now as my CMS? Finding zero examples, LOVE to learn!
https://developer.apple.com/library/prerelease/ios/documentation/DataManagement/Conceptual/CloutKitWebServicesReference/Introduction/Introduction.html#//apple_ref/doc/uid/TP40015240
If you have a CloudKit app, you can use CloudKit web services to provide a web interface for users to access the same data as your app. You must have the schema for your databases already created to use CloudKit web services. CloudKit web services provides an HTTP interface to fetch, create, update, and delete records, zones, and subscriptions. You also have access to discoverable users and contacts
As far as I understand, this is exactly the type of functionality that the CloudKit Web Services are meant for. As long as you have an application published in either the Mac or iOS App Store you can have a web presence, for instance in the form of a CMS.
Is there a reason why you think this is not possible or somehow prohibited? There is nothing preventing you from doing this in the Terms and Conditions as far as I can tell.
The CloudKit catalog sample project is a great way to get started:
https://cdn.apple-cloudkit.com/cloudkit-catalog/
Ok this a great talk at WWDC 2015, explain lots: CloudKit JS and Web Services
CloudKit.js is the new library that provides web access to your app data stored in iCloud. Explore the new web service APIs and learn how to extend your iOS or OS X apps to the web using CloudKit.
https://developer.apple.com/videos/wwdc/2015/?id=710

Apple swift - How can an app connect to existing heroku/S3 database

Im new to iOS and new to SWIFT with no previous experience with Obj-C. But, Im not new to Ruby. I have a web based app on heroku and am beginning to learn SWIFT so I can build an iOS counterpart. I need to wrap my head around the bigger picture before I can get started and I can not figure out how these apps connect to databases.
Can an iOS app connect to an S3 database...and share that database with a website? Is there documentation on this process that I have over looked.
Connecting an iOS app to a public database would really be a bad idea - all server logic should be implemented on the client, and you would also need to hardcode database user name and password in your app.
A better way is to create a server app exposing a set of REST APIs and being responsible of dealing with the database. This way you can better control at server side what the app client is able to do on the database.
If you have an order entry app, for instance, you can create APIs to:
login
register
create an order
modify an order
add a contact
delete a contact
etc...
Some of the advantages are that:
in case you need to update the logic (but not the API interface), you just need to update the server, whereas in your scenario you'd need to release a new version of the mobile app
you control and limit how client apps access to the data (preventing for instance a user to access another user's orders)
if you want to develop the same app in another platform (android, ...), you reuse the same APIs
To get started, I'd suggest you to read the AFNetworking tutorial on raywenderlch.com, focused on a ios networking library, but talking about JSON, REST, remote APIs etc.
Next you have to choose a server side technology - the most popular nowadays is node.js - to get started you can read other tutorials on the same website:
http://www.raywenderlich.com/61078/write-simple-node-jsmongodb-web-service-ios-app
http://www.raywenderlich.com/61264/write-ios-app-uses-node-jsmongodb-web-service
if you don't want to use node.js and/or mongodb... the same architecture applies, just languages and technologies differ. Just transpose what you learn from there.
If you want to read about other languages to use at server side, just google for it - if you want to use ruby, try with ios rest api server ruby.
Note: I made no mention of swift because your question looks more like an architectural problem than a language specific problem. The tutorials I mentioned here use objective-c, once you've designed an architecture and chosen the language at server side, you can start looking into how to call REST API from swift.

Azure Mobile Services - Data Access - Developing for both mobile apps and websites

I'm developing with Azure Mobile Services (using SQL Azure) to provide a backend for both IOS and Android mobile apps and a PHP website.
My question is now that now custom apis have been introduced is it considered best practice to wrap everything up in custom api calls rather than e.g. using the CRUD table operation scripts directly from apps or websites?
Additionally for data access from a website should you lock down access to stored procedures and only exec via custom apis, to enforce a consistent approach no matter who the consumer is?
While I appreciate that custom apis and the table scripts are restful it still isn't clear how to architect a solution in the most efficient, reliable way that can enforce business rules in only place allowing each process only one entry point e.g. you have a stored procedure exec'd by an api called from the mobile apps. If the website calls that stored procedure directly without going via the api it could have unwanted side effects because other logic steps will have been missed.
I'm relatively new to Azure so forgive me if I have just missed something fundamental here. I've read many blogs and tutorials but they rapidly go out of date.
Many thanks
In my opinion the great feature of azure mobile services is the push notifications (to ios, android, wp). If you are not going to use that, there's no great advantage to use WAMS
(Windows Azure Mobile Services).
But it's a good choice using Windows Azure as backend since it's easy to scale up /down. In this case, you could create a Webapi and host in a Web Role. As it works with http, you can easily create Restful services and call them from your apps (ios / android).

ios native app talking to an API or direct database connections?

Folks,
Designing an ios application, and would like to confirm my strategy. There is a database (dynamo/mongo/etc) i am building up, which the app needs to make use of. Is it smart to front the database with an API, and have the ios app authenticate against the api.
This way the app makes calls to the api instead of directly to the database?
Would you suggest node.js be a good place to start crafting the web api with?
Thanks!
Yes, access the data via an API. Whether fancy authentication is needed, depends on what is stored in your database, and what your application is designed to do. Here is one resource (among millions) on API design: http://www.vinaysahni.com/best-practices-for-a-pragmatic-restful-api
Also, here is a popular networking library for iOS: https://github.com/AFNetworking/AFNetworking
As for what technology to use, that too open ended and you will get 10 answers for every technology available. This should help though: https://softwareengineering.stackexchange.com/q/154519/44948

PhoneGap with Django Backend

I'm working on a web application that uses django.
I would like to create a native application of the site for ios / android using phone gap.
Is this possible? As I understand native devices cannot interpret python code.
It is early in the project and if it proves too difficult I may go with a different framework I.e backbone.js.
Any thoughts / experiences?
That's right, you cannot run python code on iOS or Android using PhoneGap, but there is no need to do that. Yes, you can build a native mobile application of your site using PhoneGap.
I'll try to explain a bit how these technologies compare to each other:
Django is a python web framework running on a web server
PhoneGap is a framework for building native mobile applications using web technologies (HTML5+CSS+Javascript), the application will run on a mobile device
One common approach is to build the mobile UI with i.e. jQuery Mobile and use the Django web application to provide a RESTful API to get data to the application.
Take a look at this another question for more details.
Edit: Answer the question in the first comment
Yes, it's possible to build a fast and well working application with these frameworks. The performance with today's smartphones is more dependent on the quality of the implementation than i.e. jQuery mobile and Django in themselves.
Basically with PhoneGap there are three different ways for showing the content to the user:
server side generated pages
pages generated on the client side with Javascript usin data from the server, transferred in a predefined format using for example JSON
a combination of the previous two
This answer clarifies server-client communication and page rendering quite well.
You could use PhoneGap a bit like a constrained web browser, and basically show content directly from your server as you would when the user accesses the site with a normal web browser. But I don't recommend this, though. This approach has many downsides to it (i.e. what happens when the user opens a link from your website leading to another website?)
To be accurate, at least in my opinion, UI written with Javascript and running inside an app built with PhoneGap is not native. Comparing native applications and PhoneGap applications is another thing, here is one take on explaining the differences.
I don't know what kind of service you are building, but in general I'd suggest evaluating the different approaches before starting to build an application. Would a responsive mobile optimized web site do or is there real need for what an app can provide?
If you decide to build an app with PhoneGap, I'd suggest that you do it with client side Javascript and fetch the data from the Django backend with XHR requests in JSON format. There are lots of examples available in the internet.

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