Containers for Existing .NET Apps Part 1

[Music] hi welcome to visual studio tool box I'm your host Robert Greene and today we're gonna talk about containers and joining me to do that is a dd-do guard hey everyone how are you good thanks for coming on thank you we've done containers a few times in the show we've had episodes on docker we just did as part of the smart hotel 360 series dive on the back-end services which are all containerized micro services but what I wanted to do is kind of start from scratch right go back to the beginning if you will and talk about what containers are and what some of the tooling is in visual studio to help because there is quite a bit of tooling that helps and then approach it from a different angle not so much the fancy modern micro services you know where some are in.net core and others are in Java and they're orchestrated in kubernetes and all that which is you know good stuff to know but what if I'm just somebody who's building and maintaining his built and is maintaining all right classic dotnet applications days is p.net web forms or MVC or a wind forms or WPF app that talks to WCF to talks to a sequel server right what a containers have to do with me because it turns out the answer is a lot yep for sure um yeah that's a great point so let's take a look here at what the term modernization actually means and where containers really fits into that so really we're talking about here existing absent services we're talking about so applications built with net framework usually on Prem and we want to make sure that we can move those to the cloud right without necessarily having to rewrite it as a dotnet core app exactly can do if you do decide a requirement no and there's much easier ways to move it to the cloud if you don't want to spend the time rewriting it in dotnet core so the first option you could do would be to migrate it so this really means making it cloud infrastructure ready which is really just Rijo stting in VMs so here you have don't code changes really easy but you use VM which is kind of the more traditional route right when we're talking about modernizing you can do this in a couple different ways one is making a cloud DevOps ready and this is where containers come in so containers really make it more portable lightweight easy to deploy and more DevOps ready and here again minimal very minimal code changes so you don't really have to reaaargh attacked your app at all it's really just adding some extra few lines for container support okay which is pretty easy to do and I'll go through that in a little bit and or you could cloud optimize your app and that's kind of what you were talking about before with rewriting your app we are connecting your app into dotnet core may be utilizing micro services but obviously that will require a lot more work so containers can be more of an easy step in between though it's a first step it may be the only step you need to take yeah exactly you don't have to go fully to micro services if you don't want to okay and let's take a second for and talk a little bit about VMs versus containers just so people can get a sense of what the differences are between the two so in a container what's different is that you're sharing an operating system kernel and you're really deploying the containers with the binaries libraries and the application and that's what makes it so lightweight and so portable versus a VM you actually have the operating system that for each one right it's called a virtual machine for a reason an entire machine virtualized so it's everything from the base operating system on up so they're huge they require huge amounts of disk space there's certainly scenarios where that's good they're not exactly portable not exactly lightweight the container is you take the application and all of its dependencies and that's what's in the container and then it runs on the operating system which already exists exactly Windows server or of course no server in the cloud yeah yes yes so you could have Linux and Windows so today we're focusing on Windows that's just because we're talking about dotnet framework locations so you'll have to use windows containers but yeah you can also have yet to use meniscus yes to use Windows containers exactly but if you wrote a dotnet core application and wanted to containerize that you could pick if you want to choose Windows containers Linux containers whatever you actually want to use yep Linux containers a little bit more lightweight that can be faster at the moment a little bit where they work a little bit better with kubernetes although great windows support is coming on the other hand I don't know nothing about Linux I know a lot about windows so you know there's a benefit to choosing the container that's the operating system you know about very true right so let's go into talking a little bit about docker just too many people are familiar with docker so docker is basically a container platform provider and it helps you automate your containerization so you can easily deploy your app season containers and so Microsoft actually has a set of images hosted on docker that makes this really easy for you so if you go to docker hub here you can see that Microsoft has published all sorts of images so you have your Windows server core image your dotnet images you have your asp.net images so here's where you can find kind of all of the images that these are starting points exactly take that image and then you add things to it like your application or additional functionality that you want to added you can start out with a stripped-down container and then add more things to it you could just choose the the asp net or the ASP core image which already has asp.net core running and then you can just do nothing more than put your app into it and then of course you can make any other changes you need to it to add functionality or restrict functionality right you don't have to start from scratch no you don't have to start from scratch which is great and all of these have documentation associated with them which is even better because it makes it even easier to get up and running on a very regular basis correct definitely um so let's talk first before we go into the demos about why you want to containerize your app because it's the cool thing doing it exactly that's the only reason you should do it so modernization in general can be useful for improving agility growing your applications lowering your IT costs say you have an on-prem database that you want to move to the cloud really modernization in general is about lowering your total cost of ownership containers in particular are useful because as I mentioned before you don't have to re are katuk to your code so that makes things a little bit easier for you there's less of a learning curve less code required lower deployment costs improved productivity improved DevOps ability and portability which is what we talked about with containers versus VMs I also give you some act as kind of a I know it's rightward almost l-like a firewall between you and the rest of the machine right so you could have a web app running on a machine that you wrote on dotnet 3:5 and you're leaving it there because it works fine but then people keep making changes to that machine and new versions come on or new libraries come in and now your app is subject to whatever's going on on that machine so right you know how many times is your app broken because somebody fiddled with the server you stick it in a container it's fixed that container runs on that machine then people can do whatever they want to that machine as long as they don't you know take away the ability to run a container and your app will never be affected by that and if you need to make changes to your app in the container then you go ahead and do that whether it's update to new version of the framework or apply different patches or whatever but you get this isolation that's the what I was looking for you get an isolation and the ability to move it around right oh this machine's going down for three weeks we're gonna replace it with a new machine can you get your app up and running on this new machine yeah right if you have to then go and install on that machine you know that can be a bit of a nightmare oh you say yeah here's the container run it done easy yeah yeah I mean another point there is really dev test environments as well so you hear a lot of people who are like I worked in testing on my machine weird on my machine but somehow this just yeah doesn't work in production right so that's also solved we use this app twice a year right because we have our annual poll or we have our annual raffle twice a year so you just want to you know necessarily want that up having to run all year you spin it up when you need it and you take it down containers make it really easy to do that as well so there's a lot of things agreed um so let's get into some demos so I can actually show how this works in visual studio so let's take a look at this first scenario here so a common scenario might be to have a web application and this could be an MVC F this could be a web forms up and you could containerize this you could have it talk to a sequel server also in a container for the purposes of the first demo we're just going to stick with container izing just the MVC portion of the app okay you have to put in some additional dependencies in to talk to the sequel server which I'll show you in the second demo which is a little bit more complex but let's start with the basics alright so if we go to our legacy MVC app and move the word legacy legacy means existing apps that are running the business today exactly existing business applications yeah so I've started this up already and this is basically an eShop which has a bunch of different catalog items and you can manage the catalog from this web app here so you could create new items you could edit delete do whatever you need to see meta log framework three five four four probably four something probably four seven it's cooked how was that recent okay yeah we just made these recently I think oh yeah we update them pretty regularly but it could be older if it needed okay doesn't matter what right what framework version per se so as you can see this is running locally just on my machine here so if we go back to the application in Visual Studio and I want to add docker support all I need to do is right click here and say add now before you click that mm-hmm not that this is hasn't happened to me like every day first of all you need docker installed on your local train yep and you need it running yes that's a great point yeah so I had a dollar for every time I either built this project or tried to add doctors support before I had actually started docker yeah I could retire yeah that's a really good point I automatically have it up and running at the time so I forget that that's a critical step in the process you can see by this little icon down here it's up and running another point there is that you see here it says switch to Linux containers so right now I'm running Windows containers and you have to make sure you're running Windows or Linux containers whichever one you want to choose okay so if we go into here and say add darker support it's going to auto generate a few files for us and we can walk through each of them talk a little bit about what they're doing so this first is the dockerfile and this is basically describing the environment that your app is running in so the important point here is that it's using this Microsoft asp net image yeah so this is basically the recipe for how you build this container it says if you haven't already downloaded it to your computer which can take a while go to docker hub and get this particular image window server core version 1709 with asp.net 4.7 not one that's pretty new right right so go get that file which is large it is pretty large so the first time you run this it actually takes a little bit of time to download that image and make sure it's on your machine once it's already there and unless you delete it and it's pretty quick to startup right but yeah the first time it'll be a little bit yep lengthy you also have this docker compose node that was created and this really has all of the assets to build and configure your containers when you actually run it okay so you have this docker compose file here and this is really just saying get that image that eShop legacy embassy image and it uses that docker file that I just showed you for context ok and you also have an override file and this is just defining some additional environmental variables to help it run so it's for example exposing important so the cool thing you know studio is it wraps all the plumbing for me you can do this from the command prompt many many people do yeah or you can right-click and have Visual Studio do it for you yeah and the other cool thing is these are all text files yeah so instead of having to install a bunch of things on your VM you can just go and make some changes in these text files and it's pretty easy to add dependencies add new things or configure how you need to which is very cool and you haven't touched the app nope haven't touched the apps app is exactly the same all I did was add docker support mhm so now if I start up with adding docker oops I wanted to start without debugging so you can debug into your container if you need to but for a faster startup I just started without debugging here and you can see down here it's getting these images it's making sure all the containers are ready and it'll start up the same web app now at an IP address so this is the IP address of the container itself and if that's something that you want to find out later you can even go to your command prompt say and say first you'd have to find out what the name of the container is right so docker PS is a good way to do that so that'll give you all the containers that are currently running on your machine so once you have that container ID you can say docker inspect and this is going to give you all that information about the container including what that IP address is if you now have this app running in a docker container locally on your Windows 10 machine correct exactly cool and it's running at this IP as you can see it's the same exact catalog as I showed before yep talking to sequel server not yet not yet for this one we didn't implement so if you see the docker PS only brings up your one container for this each shop legacy MVC but if this app was talking to a sequel server then the container can talk to that machine - exactly it's essentially when it's equivalent of a Windows machine running on your network yep right exactly and we'll show that in the next examples you don't have to do anything with the sequel server no no it'll be in its own container it'll just a Janee in a container though you could contain it you can't leave it where it is you could okay exactly it could be either way right okay cool easy yeah and then another thing you can do is type docker images and this is going to show you that you have that image on your machine so we have that asp.net core image right here mhm and we also have that you shop like a CNBC ok right which is so the the basic image is peanut running on core seven and a half gigs this asp net one is today they take a bit of space they do take a windows can sandurz take a bit of space of you yeah are sitting there with like 12 gig left on your hard drive then you're gonna have a hard time yeah running on that machine if you wanted to delete these images those you could also do that and you wouldn't affect things on your mission so there's also a way to there's a dr. command to take the image and put it in a tar file but you could then move to a different computer wipe all the images off if you needed the disk space great we're just playing around with it and then take the tar file and rehydrate it as images I discovered that when a while ago yeah pretty cool that's a good one too huh yeah I have quite a few images on here just because I play around with this a lot but yeah I'll probably have to clean them out at some point cool so let's get into the second scenario which is a little bit more complex but pretty similar so in this one so you have a three-tier scenario and for for this you have a WinForms front end you have a WCF middle tier and a sequel server back-end okay so this might be a little bit more traditional three-tier and to your app that you might have in your mind of business application so this is based on the same a shop example again we go back to visual studio I have this up and running just so we can show you and in four seven one you at the high DPI support isn't at all it doesn't get all crazy yes so this isn't a high DPI monitor itself okay which is why it looks a little funky here but what if you had a high if you had a hundred would automatically adjust exactly so we can do the same thing here and right click on this WCF service and say add docker support and again it's going to auto-generate some files here but we're gonna have to make some modifications this time and that's because this is only generating files just for the WCF service since that's what I right clicked on and not a docker support for it so now I want to put that sequel server in a container - okay and say ok now we have two containers and I want to make the service actually talk to the e sequel server ok so if you're gonna leave it that the WCF service talks to the same sequel server mm-hmm sitting somewhere else then you wouldn't need to yeah additional changes right there's a few changes in this base file that you need to make which is documented on the site yeah what WCF services does this have does it have all of them right no WS transport WS this that the other thing exactly you might need to add some additional things yep so first we're gonna add those additional things just for the WCF portion and all we're doing here is adding some additional things to make the environment full and this is all documented online and something you have to do when you advertising port 83 that's what that is and then if we go to the compose file here's where we're going to add the dependency on the sequel server so we will take this and this now depends on sequel data and this year is referring to the sequel server image so now it's gonna pull both that WCF image and the sequel image onto your machine so again the first time you run this it's gonna take quite a bit of time because you have to pull both of these images and on that container you've got sequel server but you'd have to put your database on and then setup your users and your security the same way you do any sequel server because again that's it is a sequel server exactly yeah the last step is to actually put that connection string info and your override files cool yes so I thought you know a lot sequel management's do you know actually I can just put in the text so I have my connection string I have my password here I have all the credentials here and I'm talking to that port 83 that I exposed okay and that's really just these in additional environmental variables right here and that's actually it so even to add support and dependency for the sequel server container there was a little bit of work but it wasn't we architected my code didn't go into my app and change it at all now it's running and now it's all set up to run in docker okay so let's start docker and this one will take a little bit more time just based on the fact that you have these two containers that need to start up so you started without the debugging which is faster but if you start with the debugging then you actually can set the breakpoints and debug the app all that's running it yes yeah you can do that as well if that's something that you need to look into right I mean presumably the apps been tested locally and works just fine but hopefully you never know it's always useful to have that option right exactly and so you can see here we've created it's creating this equal container now and now it's moving on to the WCF container you can see in the output here so if I go back here and I type in docker yes you'll see that I have I still have that container from before because I didn't do anything with it but now I have this new sequel container and when the WCF container is done that will show up here as well now in the WinForms app you need to point it to see to the WCF service running somewhere else no so that I didn't have to make any changes to the one for his front end so the wind farms was already talking to the WCF service just locally and you just had to containerize the WCF service and it can still talk isn't it running on a different yeah oh yes yes okay that's what you're saying yeah yes exactly point in the web not the app config current is to a different server yes exactly so again the I P address right exactly so now we have this starting up here and we have the service so this is the service itself and exactly we're going to take this IP address and we're going to put this into the app config file here and so right now it had the endpoint as localhost that's what we were talking to you before so this is what you'll replace with the IP address and do you get to assign names or do you always have to use IP address I have to use IP address unfortunately I don't know if there's a way to do it with the ID of the container or not I haven't looked into that at all but IP is definitely the easiest way to go so now if we start yep it's so sterile not impersonal it's true you can't name your container something something interesting so now I've started up an instance of the WinForms front-end again and that's going to be talking to the IP address I'll take a few seconds you this is so cool because you didn't have to change any of the app you just had to basically change the where the sir the pointer to the sir exactly and you Visual Studio menu obviously you need to you need to learn more about docker right but that's it's not that hard to learn how to yeah yeah exactly where the image is what does it mean how do you start and stop a container you this is really good documentation on the docker site there's you know inexpensive books you can get but you've taken this application and containerized it in 20 well we talked to 16 minutes right yeah not counting the time it takes to download the images right yeah so that would take a little bit more time sure listen now so a question I have we talked about some of the benefits of containers there's to modernize to cloud enable these things you could have taken that NBC app and published it to an azure web app you could take this WCF service and publish it to an azure web app so talk about when you might do one versus the other yeah I think there's a couple of key points so the first is about deployment so as we were talking about before you don't know what framework version this is running in and so you publish this to app service and this is running in the latest framework version but app service doesn't yet support the latest done at framework version so sometimes a gap there okay so with containers that's not an issue because your frameworks gonna come with your container and all those dependencies are kind of baked in in addition to framework it could be another third-party dependency so a lot of existing line of business applications have things like complex components or other dependencies and so all of those dependencies are really packaged in for you and you don't have to worry about installing them separately or worrying about them the second is really to improve DevOps and improve dev test environments so you can start up a test environment really easily like talked about before so you can set up your dev test environment using the container you don't in this case you don't have to even install sequel server on your right because you have it in the container the containers gonna come down to your machine and that's much easier than say installing all of that from the ground up yeah so should really help if this app was using sequel server 2010 for example and we weren't going to touch it but I've got 2017 on my machine exactly and in addition you could test it into your dev your test environment and you could be a lot more certain that it's actually gonna work in production so I think those are kind of the key things I would point out I guess also you can run containers locally you don't need a server just fine so yep you can run them locally you can deploy them to the cloud if you want to right we obviously when we DS when we talk about containers were typically you know deploying them into Azure you know for a couple reasons one because we also want to talk about Azure none of us are lugging around Windows Server machine so it's just a heck of a lot easier to put it in a jar right exactly yeah that's actually what we can talk about the next time okay that we chat so I think in the next session we can talk a little bit more about okay now we have them running in containers locally but right how do we get this to the cloud what are all the different ways you can get there how do you scale out your application we can talk about orchestrators okay which you may have talked about in your microservices episode as well a little bit yeah yeah so I think those are kind of the next steps in this scenario yeah but this is really the basics and the first part of getting towards they're cool so this is a good stopping point and we will pick this up again and the next one see you next time on visual studio toolbox bye picture [Music]

Channel: Microsoft Visual Studio

Views: 26,865

Rating: 4.7942858 out of 5

Keywords: Containers, Docker, .NET, Visual Studio, Architecture

Id: p8cAYgBIER8

Length: 29min 53sec (1793 seconds)

Published: Fri Apr 27 2018