Deploy containerized app to Fargate (Django)

In this tutorial, we will run Django SQL migrations on top of IaSQL to deploy an HTTP server within a docker container on your AWS account using ECS, ECR, and ELB. The container image will be hosted as a public repository in ECR and deployed to ECS using Fargate.

IaSQL is an open-source software tool that creates a two-way connection between an unmodified PostgreSQL database and an AWS account so you can manage your infrastructure from a database. The code for this tutorial lives in this part of the repository.

Start managing an AWS account with a PostgreSQL IaSQL db

First, make sure you have an IAM user in AWS or create one with Programmatic access through the console/UI or CLI. Ensure that the IAM role has sufficient permissions to deploy and manage all your infrastructure resources.

There are two parts to each access key, which you’ll see in the IAM console/CLI after you create it, an id and a secret. Input these in the connect account modal:

If you use the AWS CLI, you can look at the credentials configured locally. In macOS and Linux this is as simple as:

$ cat ~/.aws/credentials
[default]
aws_access_key_id = <YOUR_ACCESS_KEY_ID>
aws_secret_access_key = <YOUR_SECRET_ACCESS_KEY>

You will be able to see your PostgreSQL connection information when you press Connect.

Make sure to copy the PostgreSQL connection string as you will not see it again.

Add the necessary cloud services to the PostgreSQL database

Many different clients can be used to connect to a PostgreSQL database. For this tutorial, we'll use the standard psql CLI client. If you need to install psql, follow the instructions for your corresponding OS here.
The first migration calls the iasql_install SQL function to install the ECS simplified module into the PostgreSQL database.

psql postgres://d0va6ywg:nfdDh#EP4CyzveFr@localhost:5432/_4b2bb09a59a411e4 -c
SELECT
  *
FROM
  iasql_install ('aws_ecs_simplified', 'aws_codebuild');

If the function call is successful, it will return a virtual table with a record for each new table in your database under created_table_name and the number of existing resources or records imported from the account under record_count.

       module_name        |      created_table_name       | record_count
--------------------------+-------------------------------+--------------
 aws_cloudwatch           | log_group                     |            0
 aws_ecr                  | public_repository             |            0
 aws_ecr                  | repository                    |            1
 aws_ecr                  | repository_policy             |            0
 aws_security_group       | security_group                |            2
 aws_security_group       | security_group_rule           |            0
 aws_vpc                  | vpc                           |            1
 aws_vpc                  | subnet                        |            3
 aws_elb                  | load_balancer                 |            0
 aws_elb                  | target_group                  |            0
 aws_elb                  | listener                      |            0
 aws_elb                  | load_balancer_security_groups |            0
 aws_ecs_fargate          | cluster                       |            0
 aws_ecs_fargate          | service                       |            0
 aws_ecs_fargate          | task_definition               |            0
 aws_ecs_fargate          | container_definition          |            0
 aws_ecs_fargate          | service_security_groups       |            0

Connect to the PostgreSQL db and provision cloud resources in your AWS account

Get a local copy of the ECS Fargate examples
(Optional) Create and activate a virtual environment to install python dependencies
```
python -m venv <env-name>
source <env-name>/bin/activate
```
Install the project dependencies under the django/app folder
```
pip install -r requirements.txt
```

Create a .env file with the connection parameters provided on db creation. In this case:

AWS_REGION=eu-west-2
DB_NAME=_3ba201e349a11daf
DB_USER=qpp3pzqb
DB_PASSWORD=LN6jnHfhRJTBD6ia

(Optional) Set the desired project name that your resources will be named after by changing the IASQL_PROJECT_NAME in the my_project/app/app/settings.py. If the name is not changed, quickstart will be used.
note
The project-name can only contain alphanumeric characters and hyphens(-) because it will be used to name the load balancer

Per the Django database documentation, to connect to a new database you have to update the DATABASES in the my_project/app/app/settings.py file. This is already configured in the example project.

django/app/app/settings.py
DATABASES = {
    ...
    'infra': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': env('DB_NAME'),
        'USER': env('DB_USER'),
        'PASSWORD': env('DB_PASSWORD'),
        'HOST': 'localhost',
        'PORT': '5432',
    }
}

If you are using the template example go to step 9. The following steps explains how to instrospect an existing DB in Django.

The second migration corresponds to the Django models introspected from the modules that have been installed in the database. To introspect the schema from your database run the following command. More information here.

python manage.py inspectdb --database=infra > infra/models.py

note

After running the inspectdb command you will need to tweak the models Django generated until they work the way you’d like. In our case you will have to modify the my_project/app/infra/models.py file as follow:

Replace CharField with TextField
Remove all max_length=-1. Helpful regex for a replacement: [\s,]*max_length=-1[,\s]*
Add the following import from django.contrib.postgres.fields import ArrayField
Replace in the Service class the subnets property with subnets = ArrayField(models.TextField())
Replace in the Role class the attached_policies_arns property with attached_policies_arns = ArrayField(models.TextField())
Add related_name argument to the definition for IasqlDependencies.dependency. (dependency = models.ForeignKey('IasqlModule', models.DO_NOTHING, db_column='dependency', related_name='module'))
Add related_name argument to the definition for TaskDefinition.execution_role_name. (execution_role_name = models.ForeignKey(Role, models.DO_NOTHING, db_column='execution_role_name', blank=True, null=True, related_name='execution_role_name'))
Add related_name argument to the definition for TaskDefinition.task_role_name. (task_role_name = models.ForeignKey(Role, models.DO_NOTHING, db_column='task_role_name', blank=True, null=True, related_name='task_role_name'))

After instrospecting the db you will need to generate the migration so you can have the my_project/app/infra/migrations/0002_inspectdb.py file.
```
python manage.py makemigrations --name inspectdb infra
```
caution
If you install or uninstall IaSQL modules the database schema will change and you will need to run steps 7 and 8 to introspect the correct schema once again.
Now you can use IaSQL models to create your resources. Run the existing migrations with:
```
python manage.py migrate --database infra infra
```
The operations of the my_project/app/infra/migrations/0003_initial.py migration will apply the changes described in the PostgreSQL db to your cloud account which will take a few minutes waiting for AWS
my_project/app/infra/migrations/0003_initial.py
```
...
operations = [
    migrations.RunPython(code=quickstart_up, reverse_code=apply),
    migrations.RunPython(code=apply, reverse_code=quickstart_down),
]
```

If the function call is successful, it will return a list of dicts with each cloud resource that has been created, deleted or updated.

[{'action': 'create', 'table_name': 'log_group', 'id': None, 'description': 'quickstart-log-group'}, {'action': 'create', 'table_name': 'repository', 'id': None, 'description': 'quickstart-repository'}, {'action': 'create', 'table_name': 'iam_role', 'id': None, 'description': 'quickstart-ecs-task-exec-role'}, {'action': 'create', 'table_name': 'security_group', 'id': 31, 'description': '31'}, {'action': 'create', 'table_name': 'security_group_rule', 'id': 48, 'description': '48'}, {'action': 'create', 'table_name': 'security_group_rule', 'id': 49, 'description': '49'}, {'action': 'create', 'table_name': 'listener', 'id': 16, 'description': '16'}, {'action': 'create', 'table_name': 'load_balancer', 'id': None, 'description': 'quickstart-load-balancer'}, {'action': 'create', 'table_name': 'target_group', 'id': None, 'description': 'quickstart-target'}, {'action': 'create', 'table_name': 'cluster', 'id': None, 'description': 'quickstart-cluster'}, {'action': 'create', 'table_name': 'task_definition', 'id': 16, 'description': '16'}, {'action': 'create', 'table_name': 'service', 'id': None, 'description': 'quickstart-service'}, {'action': 'delete', 'table_name': 'security_group_rule', 'id': None, 'description': 'sgr-024274a604968919e'}]

Previously, you needed to manually build and push your image to the ECR. But recently we've added the high-level ecr_build SQL function which does all those steps automatically. It will do the following:

Pull the code from your Github repository
Build the Docker image in the directory you've specified
Push the image to the ECR repository you've provided

All of these steps will be done in a CodeBuild project in your AWS account. To use the ecr_build function, you can run:

SELECT
  ecr_build (
    'https://github.com/alantech/iasql/', -- replace with your own Github repo if you want to use your own codebase
    (
      SELECT
        id
      FROM
        repository
      WHERE
        repository_name = 'quickstart-repository'
    )::VARCHAR(255), -- replace quickstart if you've changed the project name
    './examples/ecs-fargate/django/app', -- the sub directory in the Github repo that the image should be built in
    'main', -- the Github repo branch name
    '' -- replace your github personal access token here if the repo is private
  );

After running the above SQL command to completion, you can check the running app using the load balancer DNS name. To grab the name, run:

QUICKSTART_LB_DNS=$(psql -At 'postgres://d0va6ywg:nfdDh#EP4CyzveFr@localhost:5432/_4b2bb09a59a411e4' -c "
SELECT dns_name
FROM load_balancer
WHERE load_balancer_name = '<project-name>-load-balancer';")

And then connect to your service!

curl ${QUICKSTART_LB_DNS}:8088/health

Delete Managed Cloud Resources

Delete the resources created by this tutorial using the following SQL code:

psql postgres://qpp3pzqb:LN6jnHfhRJTBD6ia@localhost:5432/_3ba201e349a11daf -c
DELETE FROM
  repository_image
WHERE
  private_repository_id = (
    SELECT
      id
    FROM
      repository
    WHERE
      repository_name = 'quickstart-repository'
  );

DELETE FROM
  ecs_simplified
WHERE
  app_name = 'quickstart';

Start managing an AWS account with a PostgreSQL IaSQL db​

Add the necessary cloud services to the PostgreSQL database​

Connect to the PostgreSQL db and provision cloud resources in your AWS account​

If you are using the template example go to step 9. The following steps explains how to instrospect an existing DB in Django.​

Login, build and push your code to the container registry​

Delete Managed Cloud Resources​

Start managing an AWS account with a PostgreSQL IaSQL db

Add the necessary cloud services to the PostgreSQL database

Connect to the PostgreSQL db and provision cloud resources in your AWS account

If you are using the template example go to step 9. The following steps explains how to instrospect an existing DB in Django.

Login, build and push your code to the container registry

Delete Managed Cloud Resources