I'm currently developing a SOA based architecture in Azure, using disparate Web API services (they'd probably qualify as Microservices, but I'm hesitant to use the term).
I have a service which is triggered by the Azure Scheduler. It does some "stuff" and then needs to call another Web API (via HttpClient) service to trigger something else. To do this, I need to know the URI of the 2nd service. When running locally, this is fine, as it is something like
POST http://localhost:1234/2ndService/api/action
However, when I deploy to Azure (using Internal Only as the access level), it gets an obfuscated URI, such as http://microsoft-apiapp8cf3d453-39d8-4b3b-ad00-e9d8008a9b58, which I obviously can't guess at deploy time.
Any ideas on how to solve this problem? Or have I made a fundamental error here?
Instead of relying on public http endpoints, have you considered passing messages via queues in Azure Table Services? It's very simple to do and is going to be more robust since you can take advantage of built-in features like guaranteed message delivery.
The overall idea is that Service A does some "stuff" then puts a message on queue ONE. Service B continuously reads from queue ONE until it picks up a new message from Service A (or any other service for that matter) and then does its "STUFF". You can continue to chain calls like this to other services that need to be notified.
If you want a more elegant solution you can look at using Service Bus Topics but the concept is basically the same.
Also, since you mentioned that your architecture is much like microservices, you can check out the new Service Fabric which is designed for your scenario.
In case of Azure Web Apps, you may always see such properties going to the web app dashboard, then properties. When deploying from the Visual Studio, you can set the URL as you want - just checked it, and it works fine.
Not very clear what technology do you use - is it IaaS VM? Is it Web Apps?
From my standpoint, each service should be deployed as a separate Web App (or API App, if you want). Each Web App has defined its own name as in yourwebapp.azurewebsites.net, so once you have provisioned the Web App no 1 in Azure, you know its address so you will call it from the Web App no 2.
In all the cases, you should have fully qualified domain names, and not local/internal ones.
Related
I have a service, (.net core 3.1), that receives messages, a lot of them, and stores them in a DB.
The original is baked into an API and deployed as an App Service.
The App Service works fine. Great for the API and the Web but I'm uncertain whether it's the best choice for the service which I now intend to separate from the App Service. It's more or less background worker that just collects data and saves it.
I would like to know if there are any other more suitable Azure products other than App Service or should I go with another App Service?
It seems your use case basically fits to serverless scenario. All your messages processing can be handled by Azure Function.
https://learn.microsoft.com/en-us/dotnet/architecture/serverless/serverless-business-scenarios
https://learn.microsoft.com/en-us/dotnet/architecture/serverless/serverless-architecture
I have developed a windows service. i need to deploy it in Azure App Service. Please someone explain me how to do that. Is there any way to install it on console or any other option.
You can't deploy a Windows Service using App Service. One option is to convert your code into a Web Job. Another option is to use a Virtual Machine instead of App Service.
Azure App Service is the service that should be used for Web/Mobile and basically is the web-server-as-a-service. You have almost no access to the underlying system, and system-wide actions like a working windows service is likely impossible.
I see three ways:
1) Migrate to Worker Role, but it is classic model. There is a good article on how to do that, i took a look and did not see any potential problems. It is more simple way.
2) Migrate your windows service to Web Job and run it as a background service. It will need you to rewrite some parts of your service, i think - but there are supported executable formats out-of-the-box. Take a look at how it works.
3) Take a look at Azure Functions - it is "trigger-and-invoke" service that can be used for listening for events and executing actions.
But, if you need to catch some events from DB, then i am not sure that it will be possible with that, because Web Job is more like a service that listens for external events, and yours scenario looks like you want to catch events from the same server. That way, i would recommend you to place it on a virtual machine to avoid the rewriting or migrating time-consuming issues.
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.
I have an MVC front end application (relatively small) with its own DAL implementation using repository pattern. I am thinking of moving the DAL in its own WebAPI project to maintain cleaner separation. The MVC app is hosted in Azure using a cloud service (web role). The WebAPI will only be used by the front end application and would not be exposed to any other external application for now, but even then i would still want it to be hosted as a separate app/web/worker role rather than keeping the DAL in same project.
Would it be a good idea to:
1) Host the WebAPI project within the same Cloud Service as a Web/Worker role or should I create a new website/cloud service for hosting it? Using the same cloud service is preferred keeping the cost factor and n/w latency issues in mind.
2) If I host in same cloud service, what is more advisable to use for web api project - web or worker role?
3) Somewhere i read that I should make use of Service Bus in Azure for interaction between MVC frontend and WebAPI backend. Is this the suggested way of doing it or is there any simpler way of getting it done?
I would suggest you to use the same cloud service. The reason being complexity and failure scenarios, when you split your app into multiple cloud services the problem comes when you are updating them service from your source control
You will need to do two deployments and make sure they are in sync etc.
I would keep the service runtime simple in one cloud service.
Again it is preference and comfort, if you really want to separate them at code level and know they will work fine. The two cloud services should be OK.
From experience, refactoring decision like these add a lot of work in the future. Positive or negative depends on your understand of the problem and the image of the bigger picture you have in your head that cannot be put on paper :).
Happy to Help, Yours Truly -CB
I'm looking into moving an existing app to Azure. It will have an MVC app in one web role and some WCF services in another web role. When live, the site will live at http://www.myapp.com and the services will be at http://api.myapp.com with the MVC app configured to point to the services at http://api.myapp.com.
The problem is when pushing the app to the "stage" configuration on Azure. My understanding is that each push to stage will cause the services to live at a new url (something random like http://4aa5ae2071324585ba5a902f4242a98c.cloudapp.net/). In this case, what is the best way for my MVC app to discover the url of the services?
One option would be to setup a dns entry like http://stage.api.myapp.com and update my DNS CNAME record to point to the new Azure staging url every time I push to stage, but... yuck.
Another option would be to push to stage, get the new urls for the services, RDC to each instance of the MVC role and manually update the configurations. Also yuck.
Is there a simple way to do this? I know I could automate some of the steps above with something like PowerShell, but I'm really hoping there's something baked into the Azure framework that makes this easy. It seems like it would be such a standard scenario.
The only way to dynamically discover what the staging URL will be is to have the instance check its own deploymentID. I am assuming here that the MVC website and the WCF service are in the same deployment. If you check the RoleEnvironment.DeploymentID, you will find that this corresponds exactly to the 'random' URL used in staging (i.e. http://[deploymentID].cloudapp.net).
As long as you are dynamically creating the ChannelFactory on the clientside, it should be able to take its own DeploymentID and find the staging URL.
Of course, this is only useful when deployed in staging. Why don't you simply use the Production slot? That name is stable and you can rely on it or the CNAME (more likely) that you set for it. You can always have multiple hosted services (dev, QA, prod, etc.) and just use the production slot on them.
Don't do what #dunnry is suggesting! Azure has a really good concept of endpoints that solve your problem. And you have access to this info from your RoleEnvironment class.
You can take a look at my blog post on how to get the endpoint from the client. The key part is to create an internal endpoint at which your WCF service is listening. Keep in mind though, you don't necessarily need a new role for this, and personally, I would rather host it in IIS alongide the original Web role & have two of these roles for improved reliability.
This way, it doesn't matter what the deployment is, because the service communication will take place inside that deployment, be it staging or production.