Using Azure MobileServices library with my own LAN WebApi - azure

I am currently doing some research for the development of a mobile application for our company that should support offline data sync (on an iPad). We have explored many possibilities including PhoneGap/Cordova, Xamarin and simply native iOS development. Xamarin, for many different reasons, seems to be our best choice, so my question will assume we will develop in Xamarin.
I was looking into a library for managing offline data synchronization and the most obvious solution is Microsoft Azure MobileServices. However, my company is Canadian, and apparently it's hard to trust (legally) our data to clouds based in the US. Since we already deployed internally our WebApi on our intranet, I figured there was probably a way to point the MobileServices library to our own WebApi. I have read about the Azure Hybrid Connection possibility, but our data still conveying through Microsoft servers might not be a possibility. So, my question is this:
Is there a way to configure the Microsoft.WindowsAzure.MobileServices Client library to point directly to our intranet, RESTful WebApi backend, without going through any Microsoft Azure servers ?
I understand that, in order to be able to use the Client librairies seamlessly, we probably would have to adapt our WebApi to implement the necessary .net Backend interfaces. I'm mostly wondering if it's even possible as the MSDN documentation on the libraries all seem to point to direct connections to their servers (no possibilities to configure your own connection strings) and all instructions redirect you to their Azure Mobile Services website.
Thank you.

If you look at the API for your mobile client, you'll notice that the Azure Mobile Services Client SDK only cares about two things:
new AzureMobileClient( url, appkey)
...where it's hosted shouldn't be a concern. Everything else is just configuration.
If you want to host the Azure Mobile Services Backend on your own servers, technically you could do this, but there are likely a few caveats. Microsoft has announced that they will be launching a Canadian Azure data center, but we won't see it until 2016.
In the meantime, here's how you can host the services locally. Note that I have not tried to emulate all of the features of Azure Mobile Services (aka Zumo) so your mileage (or kilometerage) will vary.
Hosting Locally:
From a technical feasibility, you absolutely can run the services locally. I know this because you can create the Azure Mobile Services Backend project from within Visual Studio and run it locally for development purposes. This is what our development team does for testing their mobile applications.
Note that you can create the Azure Mobile Service backend directly from within Visual Studio: New Project -> Cloud -> Azure Mobile Service. You can also download the exact same template (pre-configured with your URL and ApplicationKey) directly from the Azure dashboard: Create -> Mobile Service.
Obviously, if you're hosting it on your server it will be up to you to configure and use a proper SSL certificate for your site.
ZUMO Permissions:
By default, the security roles on the server are turned off. So if you're locking down any of your methods using the [AuthorizeLevel] attribute these settings will be ignored at runtime. If you need to enable this feature you can do so by modifying the WebApiConfig.Register() method and marking the site as self-hosted: config.SetSelfHosted(true).
Configuration:
From a configuration perspective, the Azure Mobile Service dashboard provides several tabs for configuring Identity, Push Notifications, Connection Strings and App Settings. Sadly, you won't have a dashboard, but all of these settings have a corresponding value in the local web.config. Any value you provide here is automatically overwritten in Azure, but they're used when running locally.
The minimum settings you'll need to configure are listed here. The ApplicationKey you can distribute with your ZuMo client, but the MasterKey is for the Admin authorization level so you'll want to keep that secret. The MobileServiceName is used by the EntityFramework for your database schema and what appears in the URL of your site.
<add key="MS_MobileServiceName" value="myzumosite" />
<add key="MS_MasterKey" value="masterkey" />
<add key="MS_ApplicationKey" value="appkey" />
Values that start with a MS_ prefix map to corresponding values in the Azure Portal. MS_GoogleClientID and MS_GoogleClientSecret map to the Google Identity values in the dashboard, for example.
Any other value in the AppSettings node is immediately accessible via the ApiServices.Settings property and corresponds to the Settings node in the Azure dashboard.
Database connection strings continue to exist in the connectionStrings node. The same is true for azure notification hub.
Database:
Obviously, the database you configure will be up to you as well. Permissions and User accounts are also obvious. There may be some minor differences between the SQL Azure syntax for Entity Framework database migration scripts that you'll need to worry about. (I've discovered the database migration scripts don't work from the Package Manager, but they do work when the database scripts are run when your website starts)
Caveats:
You will not have a nice dashboard for monitoring performance of your site, reviewing logs or changing runtime settings
You will not be able to scale out your site immediately; Scaling and deployment will be your problem
Deployment configuration is your responsibility (Project -> Publish won't be available unless you configure it)
Not sure if you'll be able to use Azure Active Directory as an authentication scheme, though from the sounds of it that won't be a concern. You can write your own authentication providers: Microsoft's Zumo library only supports a handful, but the underlying Owin.Security package that Microsoft uses supports several dozen systems!
Your site will need to be publically visible to your mobile clients
Push Notifications should work, but you will be using Azure's notification hub for this.
I have no idea where ApiServices.Log will go
The easiest path to take would be to:
Create the Mobile Service in Azure to get the notification hub and settings preconfigured
Download the starter site from the dashboard
Configure the web.config as mentioned here.

It's not possible to simply configure WAMS Client library to work with your own WebApi Backend.
But WAMS library is available at github, so I'm sure you can reuse a lot of code from the WAMS project, especially if you want to use a PCL project.
To route your data securly through Azure, you could think about setting up express route. Additionally, for last weeks update, it's possible to apply a custom domain to the WAMS Backend, including your own certificate to secure your connection.

Related

How can I use AAD for an Azure version of "Windows Authentication" from a Web App to a Web API App?

I have two applications:
MVC Site (User-facing Web App secured via OAuth -> Google)
Web API Site ("Private" Web Services)
These are hosted in an App Service Plan in Azure. These web services will only be consumed by my own applications - I don't need to worry about outside consumption. In fact, I specifically don't want outside consumption. My Web App is using OAuth to Google - that shouldn't matter here.
So to get to the heart of my question: My web services currently have no authentication/authorization model in the code but I don't want it just publicly available to anybody. On prem, we just lock this down via IIS using Windows Auth and set the service account for the consuming web app to run as a user that Windows Auth allows access to. I'd like to do the equivalent in Azure.
I understand Azure isn't exactly the same but I have to believe this is possible. I have even gotten my web services locked down the way I want using the settings in the Authentication/Authorization tab (I can try to navigate to it but I only get my Swagger UI once I login with a valid organizational account). So half of my battle is solved but I cannot figure out how to do the other half - the equivalent of setting the service account for my consuming MVC application to run as.
Can I do this via the portal without having to code specifically to this scenario? I'd really like a PaaS-level or IaaS-level solution for the security portion of consuming the above locked-down services. I'm also open to other avenues if I'm going down the wrong path in having a PaaS or IaaS security solution to this problem. I'm not against making code changes - we did have a one-liner in our RestSharp code to engage Windows Authentication, but the bulk of the work/configuration was outside of code and that's what I'm going for here.
If going the IaaS path you can host the application inside of an VM in the exact same way as you did before when running it directly on-top of IIS. The benefit is that you can get running the same way as before but you will still need to manage the VM; i.e install updates and take care of its security.
However, if you want to have a PaaS solution, then you need to modify the code of your front-end application to pass on the authentication token to the back-end API, assuming the back-end accepts the same authentication as the front-end. See https://azure.microsoft.com/en-us/documentation/articles/app-service-api-dotnet-get-started/ as an example on how to pass on authentication information from one app to another.
Alternatively you can use the app identity to make calls to your back-end API. This way the calls are not related to any user but are instead done in the context of the app. See https://github.com/Azure-Samples/active-directory-dotnet-daemon for more details on how to set it up, both configuration and needed code.
If you want to allow your users to sign-in using their Google accounts then you could handle authorization to your API using the app identity (second alternative above), assuming the API is independent of the requesting users identity.
Enabling authentication for a Azure Web App directly through the menus in the Azure Portal adds Azure AD authentication in-front of your application and require your to pass an access token generated by Azure AD to your API for it to work.

How to configure Azure Mobile Service to populate custom dashboard

I have been doing quite a bit of research into Azure's various offerings and what they can do, however, it is quite hard to figure out how they might fit together. I have set up a Mobile Service to act as my mobile app's back-end, managing push notifications and data storage etc. This populates a SQL database I have provisioned, all good so far. However, I would now like to display this data in a dashboard type web app. Do I create a private API and host it on another Azure App Service and call it from a separate web app which populates a dashboard, or populate the dashboard directly by querying the SQL database? Not sure of the security implications of either set up, or implementation issues?
Azure App Service can combine both mobile and web components. You didn't mention the preferred language, but ASP.NET (MVC5) and Node.js are supported for the mobile component.
If you have not started using the Mobile Service in production, add the Mobile Apps SDK to your website, update the client SDK to point to the Mobile Apps SDK and just have one site.
Refs for the Server SDKs:
* node
* ASP.NET
Your best bet here is probably to create an empty Web App Service (Website) and have the Mobile Service populate the data on this website, in order to visualize it.
So keep the Mobile Service you have now, and connect it to a new website.

Azure mobile services vs Azure App service vs plain Web API

Can anyone please point out any benefits of using Azure Mobile services vs using a plain Azure app service / clean web api? For a starter / project type for a backend mobile solution.
I have somewhat mixed feelings on why I would want to use Azure Mobile Services.
As far as I see on Azure Mobile services you have an easier way of authenticating, you can use the notifcations hub more easily
and you have the different "built-in" ways of handling data (table storage etc).
Usually you would want some custom logics, user registration and handling when users register to your backend and you would like a more solid way of handling
and storing the data not privided by the OOTB datastorage.
You might also have another preference than using the /Table/ odata-endpoint you get with it or end up doing lots of logics to make your DAO's return data in properly for the OData endpoints.
All these things; IMO makes it more difficult to make the API/backend clean when using Azure Mobile services rather than a simple Web API with OData endpoints and swagger documentet API that can be used in a mobile-app just as easy.
Implementing / handling authentication and notifications ++ in Web Api ain't that diffucult nor time consuming.
So my problem Azure Mobile services is that it tends to fine for dev / prototyping and testing, but it might get really messy really fast when developing a proper backend.
Any thoughts and reasons why one should choose one instead of the other?
Think of Azure Mobile Services as V1 and App Service/Mobile App as V2. While Microsoft hasn't announced that Mobile Services will be phased out in the near future, if you start a new project, you should definitively look at App Service.
due to the fact that many people are confused about wether to take Web API or Web App or something different. They are going to put it all under one name. The underlying technology will be the same "i think".
But now you'll have in your portal the opportunity to add mobile push notifications, or add your swagger api definitions.
So when you're goint to stick with App Services you're not going to limit yourself.
Even when you're going to take Web Api you'll get all the functions as if you would take an App Service (if i'm correct).
*Edit: I looked it up in the portal. As I said, my old Web App Projects have the same settings as Web Api projects. So you don't need to decide anymore which kind of project you're taking. You get all the benefits out of the App Service.

IMobileServiceSyncTable with generic API server

We have built a simple mobile app that connects to ASP.net Web-API 2.
We would like to use Microsoft client SDK for it's offline sync support.
Now that Azure Mobile Apps support custom authentication we could actually take the leap.
I want to know out if the offline sync SDK absolutely requires us to use Azure Mobile App or Azure Mobile Services.
Microsoft documentation is full of how-to guides but does not explain what happens under the hood. The best I could understand, both are just OData rest API's and swagger for documentation.
Can the Azure Mobile Client SDK work with API server created on top of ordinary ASP Web-App, outside Azure?
What is it about the Azure Mobile App that makes the magic happen?
Vladmir,
On top of OData, in order to support features like soft delete, offline sync and others, the Azure Mobile Client SDK expects the server to implement a certain protocol. So although the answer to your question:
[does the] sync SDK absolutely requires us to use Azure Mobile App?
... is no, and in theory, you could implement your own API, but I would recommend against doing so, since (among other reasons) even if you manage to implement the expected conventions and behaviors, this will become a maintenance challenge down the road if you need to upgrade the client SDK to take advantage of bug fixes and/or new features.
The good news is that with the latest release of the Azure Mobile Apps server SDK, adding mobile capabilities to an existing ASP.NET Web API application is trivial, and you should be able to enable the scenarios you're looking for simply by adding the appropriate Table controllers. So you can just enhance your existing application and not have to develop and maintain the Azure Mobile Apps specific logic yourself.
About your last question, since both, the client and the server SDK are both open source and developed in the open, you can look at what what makes the magic happen here:
https://github.com/Azure/azure-mobile-apps-net-server
https://github.com/Azure/azure-mobile-apps-net-client
I hope this helps!
The answer for your first question: Yes the SDK can be used in any Server API you have since it will be your entry point to work with Azure Mobile Services.
The Azure Mobile app creates a mobile services instance which has push notifications and SQL tables to store all messages you would like to send with the capability to customize the message as needed. Also it creates a notifications hub instance under the hood to manage notifications for all mobile platforms. Azure mobile apps provide offline capabilities through native sync services between db on your devices and the server when connectivity is present.
Feel free to ask more questions to have a full understanding on How mobile apps works.
Hope this helps.

Windows Azure and MVC5 - How to use same database schema for desktop and mobile versions?

I have developed an MVC5 web application which uses Code First Migrations to build out the database. Now I am attempting to develop a mobile app (using PhoneGap if that matters) that exists as a native option to access the data of the application. However, I am having trouble finding a way for the databases to work nicely together.
Ideally, I'd like to use the same database schema entirely, and just have the application and the mobile app point to it. The database is hosted on Windows Azure. The issue I'm having is that with Azure, the standard way of handling databases with mobile apps is to use an Azure Mobile Service. However, when that service creates a database, it creates its own schema named after the service, whereas the web application uses the dbo schema. So the Users table might exist in dbo.Users for the web app, but in myAppName.Users for the Mobile Service.
I've already explored this solution, which seems to mirror my problem. However, there is an additional issue. The .NET MVC5 Authentication services use dbo as the default schema and there seems to be no way to change that.
Bottom line, if I use the default schema, the mobile app cannot access the database, but if I move the tables to the Mobile Services schema, the Login/Authentication fails because the tables don't exist in the default schema anymore.
Am I missing something here? It seems like it should be a fairly common task to have a web app and mobile app accessing the same database, but I've been investigating this for days without finding a solution.
Thanks for any help you can provide.
The standard way of using a database for mobile apps in Azure is not Azure Mobile Services. I mean, I would not call it standard but just one of the options.
When Azure Mobile Services creates a database it does not create the database with its own schema. Azure Mobile Services does not have a predefined schema. You can define your own schema. The only predefined logic is the addition of the azure mobile services tenant name as a prefix to all table names. This is done to help you host multiple azure mobile service accounts in a single database. You can override this logic if you write the app in .NET. I'm not sure if that's possible if you roll a JavaScript based Azure Mobile Services account.
My suggestion to you would be to roll your own ASP.NET Web API project and host it in Azure. You can host in Azure Web Sites or Cloud Services according to your requirements. Once you have your own APIs running in Azure you should have no problem accessing the APIs from a web site or mobile app.
Hope this helps.

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