complex-docker-project: A JavaScript repository from dangchinh25

To deploy multiple container running on one EC2 instance using Elastic Beanstalk, we need a Dockerrun.aws.json configuration file, which is specific to Elastic Beanstalk.
When writting the configuration file, note that we have to specify AWSEBDockerrunVersion=2, because version 2 is to handle multiple container. The format differs significantly from the previous version 1.
Further reading: https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create_deploy_docker_ecs.html

To handle path routing/load balancing we can use Nginx, which can be used by simply writting a config file, in this application it is the nginx/default.conf file.
Further reading: https://docs.nginx.com/nginx/admin-guide/load-balancer/http-load-balancer/
Inside the file, we have 2 kind of directives, upstream and server - The upstream directive is to specify a group of server that will handle the traffic. - Below is a group named client and only consists of 1 server client host on port 3000, noted that the server directive here is diferent from the outer server directive. Here, the server is just a list of server (in this application, the server name is taken from the container name set by the docker-compose.yml file) that will handle the traffic passed to this group. upstream client { server client:3000; } - The server (outer) directive is to list all the path routing config to a virtual server running on Nginx. The location is followed by a template of incoming traffic, and the proxy_pass indicates the upstream group that will handle that request. - In the snippet below, the server will route all request prefix with /api to the api upstream group and the remaining requests will be handle by the client upstream group.
```
 server {
     location / {
         proxy_pass http://client;
     }

     location /api {
         proxy_pass http://api;
     }
 }
```

dangchinh25/complex-docker-project