osconfhyd-talk: An HTML repository from inovizz

Docker Compose Demo Application

The demp application primary has three microservices

Flask App
Redis backend
Celery based queue mechanism

Flask API & Celery service both talks to Redis backend and all of these three have to be deployed in separate containers.

Create an AWS Docker context and list available contexts

To initialize the Docker ECS integration, you will need to run the setup command. This will create a Docker context that works with AWS ECS.

➜  example git:(master) ✗ docker ecs setup
Enter context name: aws
> new profile
Enter profile name: sandbox
Enter region: ap-southeast-1
Enter credentials: y
Enter AWS Access Key ID: *************************
Enter AWS Secret Access Key: ***************************

You can verify that the context was created by listing your Docker contexts:

$ docker context ls

Test locally

The first step is to test your application works locally. To do this, you will need to switch to using the default local context so that you are targeting your local machine.

docker context use default

You can then run the application using docker-compose:

docker-compose up

Once the application has started, you can navigate to http://localhost:5000 using your Web browser using the following command:

open http://localhost:5000

Try out all the APIs are working file. Primarily there are two things to check -

localhost:5000 will be serving an HTML template, which will eventually to talk flask server and that talks to Redis bacekend
Second thing to test is /download API, in which Flask App talks to celery service and sends a background task to take place

Push images to Docker Hub for ECS (ECS cannot see your local image cache)

In order to run your application in the cloud, you will need your container images to be in a registry. You can push them from your local machine using:

docker-compose push

You can verify that this command pushed to the Docker Hub by logging in and looking for the timestamper repository under your user name.

Switch to ECS context and launch the app

Now that you've tested the application works locally and that you've pushed the container images to the Docker Hub, you can switch to using the aws context you created earlier.

docker context use aws

Running the application on ECS is then as simple as doing a compose up:

docker ecs compose up

Check out the CLI

Once the application is running in ECS, you can list the running containers with the ps command. Note that you will need to run this from the directory where you Compose file is.

docker ecs compose ps

You can also read the application logs using compose logs:

docker ecs compose logs

Check out the AWS console

You can see all the AWS components created for your running application in the AWS console. There you will find:

CloudFormation being used to manage all the infrastructure
CloudWatch for logs
Security Groups for network policies
Load balancers (ELB for this example / ALB if your app only uses 80/443)

Checkout CloudFormation

The ECS Docker CLI integration has the ability to output the CloudFormation template used to create the application in the compose convert command. You can see this by running:

docker ecs compose convert

Stop the meters

To shut down your application, you simply need to run:

docker ecs compose down

Steps for Deploying Containers on ACI (Azure Container Instances)

The first thing we have to do is login to azure using below command, it will open up Azure Portal page for you to login and enter creds, once you do that, the login will be successful on CLI.

docker login azure

Post that, the same way we created context in the case AWS ECS, we'll now create context for Azure ACI.

docker context create aci azure

Now, let's switch to Azure Context using below command -

docker context use azure

Once it is done, we can check the context using following command -

docker context ls

It should be giving similar output -

After that it the same as we saw in AWS ECS deployment -

docker compose up
docker ps

Above commands can be used to deploy the containers and check the current status of containers deployed.

To clean it up we can use

docker compose down

Some part of this demo application is taken from a demo which happened in AWS Cloud Containers Conference on 2020-07-09. Rest part of the code is added to introduce more complexity in sample code. All credits of code are with this original repo - https://github.com/docker/ecs-plugin/tree/master/example :)

inovizz/osconfhyd-talk