This is a multi tier, minimal functionality ASP.NET Core MVC application. The purpose of this application is to both test and demonstrate how an ASP.NET Core application can be deployed and managed by Habitat.
This repo contains the following key parts:
The actual application is in the root of the repo and has the typical folder structure of an MVC application.
The habitat folder includes the habitat plan, hooks, and necessary configuration that builds the application into a hart package.
The hab-mysql folder includes a habitat plan for building MySql for Windows.
The hab-linux folder contains a bash based plan for deploying a linux package on docker.
The hab-migrations folder contains a plan for a linux based package used to simply run database updates and create the initial database. When MySql runs in docker, this is helpful because it is diffucult to run the migration from the host. However, it would be beneficial to build one for windows as well.
In order to succesfully build and run this application inside habitat today, the following prerequisites exist:
- You are using
hab.exeversion 0.20.0 or later. Note that 0.18.0 and above is usable but lacks the multi service spervisor if running the mysql and ASP.NET Core services on the same instance. $env:HAB_WINDOWS_STUDIOis set to any value. I like1but your preferences may vary.
Eventually this last prerequisite will no longer be necessary.
git clone https://github.com/habitat-sh/habitat-aspnet-sample
cd habitat-aspnet-sample
hab studio enter
build hab-mysql
build habitat
This will pull down this repository, enter a Windows habitat studio and build the MySql and ASP.NET Core sample plans. Note that both of these packages are also available from the windows based depot if you do not want to build them locally.
On linux we can use the mysql plan in core-plans and you do not need to build it. For the ASP.NET Core application, you will want to enter into a docker/Linux based studio and build the plans both in hab-linux and hab-migrator.
git clone https://github.com/habitat-sh/habitat-aspnet-sample
cd habitat-aspnet-sample
hab studio enter
build hab-mysql
build hab-linux
build hab-migrator
While still in the studio:
VM:
hab start core/mysql
A new window will open and start a habitat supervisor running mysql on port 3306 in the default service group.
Docker:
docker run -e HAB_MYSQL="$(cat hab-mysql/default.toml | Out-String)" -it -p 3306:3306 core/mysql --group dev
You will need to be in the root of the sample application on the same machine running the database:
VM:
hab pkg install core/dotnet-core-sdk
hab pkg exec core/dotnet-core-sdk dotnet restore
hab pkg exec core/dotnet-core-sdk dotnet ef database update
Docker:
hab studio enter # Enter docker container studio
build hab-migrator
hab pkg export docker core/sample-migrator
exit
docker run -it core/sample-migrator --group dev --peer 172.17.0.2 --bind database:mysql.dev
This only needs to be done once for the lifetime of the VM or container or after changing schema.
VM:
hab sup load core/habitat-aspnet-sample --bind database:mysql.default --strategy at-once
Note that when adding services to a supervisor already running as we are doing here, we use hab sup load to load the service into the supervisor. We should see the ASP.NET Core service starting in our separate supervisor window. We use --bind to bind the connection string in the ASP.NET app to the MySql service's configuration. We also turn on the --strategy at-once so we can watch the application update itself when we upload new harts to our depot.
Docker:
docker run -it -p 8090:8090 core/habitat-aspnet-sample --group dev --peer 172.17.0.2 --bind database:mysql.dev
The Vagrantfile included will start 4 VMs:
-
hab1-hab3: Windows Server 2016 machines. Their firewalls will be configured, and environment variables permanently set. TheVagrantfileassumes that you keephab.exeand its dependencies inc:/habitatand will sync that to the vm and put it on the path. If you keep this file in a different location, adjust theVagrantfileor copy the files to the above location. -
haproxy: An Ubuntu 14.04 vm that installs the current linux version of habitat.
These machines are configured to work with the demo_script in the root of this repo.
You need at least three services running the ASP.NET sample in order to perform a rolling update. If you would like to have each service run on its own VM (containers are coming), there is just one bit of server prep you should perform:
New-NetFirewallRule -DisplayName "Habitat TCP" -Direction Inbound -Action Allow -Protocol TCP -LocalPort 9631,9638
New-NetFirewallRule -DisplayName "Habitat UDP" -Direction Inbound -Action Allow -Protocol UDP -LocalPort 9638
Alternatively you can use the Vagrantfile in this repo to provision these machines with vagrant.
You only need to start the MySql service on a single vm just as you did above. You will also need to create the sample app database as was done above too. Then start a habitat-aspnet-sample service on each VM:
hab start core/habitat-aspnet-sample --bind database:mysql.default --peer 192.168.137.95:9638 --strategy rolling --topology leader
Note that this assumes that 192.168.137.95 is the ip of one of the nodes running the service. It can be any one but it has to be running. Since it is likely you have already started the mysql service, you can use its ip.
Once the third service is started, all of the services will run the sample application. Now if you upload an updated application to the depot, you can watch each service start one by one.