Deploy the application

In these steps, you’ll use the docker-stack.yml file to deploy the voting application to the swarm you just created.

Copy docker-stack.yml to the manager

The docker-stack.yml file must be located on a manager for the swarm where you want to deploy the application stack.

1. Get docker-stack.yml either from the source code in the lab or by copying it from the example given here.

   If you prefer to download the file directly from our GitHub repository rather than copy it from the documentation, you can use a tool like curl. This command downloads the raw file to the current directory on your local host. You can copy-paste it into your shell if you have curl:

    curl -o docker-stack.yml https://raw.githubusercontent.com/docker/example-voting-app/master/docker-stack.yml
   

   Tips:

   • To get the URL for the raw file on GitHub, either use the link in the example command above, or go to the file on GitHub here, then click Raw in the upper right.
   • You might already have curl installed. If not, you can get curl here.

2. Copy docker-stack.yml from your host machine onto the manager.

   $ docker-machine scp ~/sandbox/voting-app/docker-stack.yml manager:/home/docker/.
   docker-stack.yml                                                                      100% 1558     1.5KB/s   00:00
   

3. Log into the manager node.

   $ docker-machine ssh manager
   

   The ssh login should put you in /home/docker/ by default.

4. Check to make sure that the .yml file is there, using ls.

   docker@manager:~$ ls /home/docker/
   docker-stack.yml
   

   You can use vi or cat to inspect the file.

Deploy the app

We’ll deploy the application from the manager.

1. Deploy the application stack based on the .yml using the command docker stack deploy as follows.

   docker stack deploy --compose-file docker-stack.yml vote
   

   • The --compose-file option specifies the path to our stack file. In this case, we assume it’s in the current directory so we simply name the stack file: docker-stack.yml.

   • For the example, we name this app vote, but we could name it anything we want.

     Here is an example of the command and the output.

   docker@manager:~$ docker stack deploy --compose-file docker-stack.yml vote
   Creating network vote_default
   Creating network vote_backend
   Creating network vote_frontend
   Creating service vote_result
   Creating service vote_worker
   Creating service vote_visualizer
   Creating service vote_redis
   Creating service vote_db
   Creating service vote_vote
   

2. Verify that the stack deployed as expected with docker stack services <APP-NAME>.

   docker@manager:~$ docker stack services vote
   ID            NAME             MODE        REPLICAS  IMAGE
   1zkatkq7sf8n  vote_result      replicated  1/1       dockersamples/examplevotingapp_result:after
   hphnxyt93h42  vote_redis       replicated  2/2       redis:alpine
   jd0wafumrcil  vote_vote        replicated  2/2       dockersamples/examplevotingapp_vote:after
   msief4cqme29  vote_visualizer  replicated  1/1       dockersamples/visualizer:stable
   qa6y8sfmtjoz  vote_db          replicated  1/1       postgres:9.4
   w04bh1vumnep  vote_worker      replicated  1/1       dockersamples/examplevotingapp_worker:latest
   

What’s next?

In the next steps, we’ll view components of the running app on web pages, and take the app for a test drive.