Perry The Docker Agent

Your cool remote docker agent in the cloud ⛄️

Based on remote-docker-aws 🙏🏾

Use docker to develop services, but without the overhead of running docker on your machine! This is a development tool that you should use if your machine is low performance, or if you are running many docker services.

Why is this useful?

Frees up your local machine for useful tasks such as running your code editor, browser, and email, leaving running Docker to a dedicated server instance. The result is that your local machine functions faster, uses up less disk space, and consumes less power. MacOS users will also see noticeable speed improvements since Docker on Linux (which is what the remote hosts runs) is much more performant.

The downsides:

• SSH tunnel communication is slower than local communication. However using an AWS region with low ping makes the latency unnoticeable. Find the region fastest for you using this site
• Some more setup required to get everything configured properly and running (tunneling ports, syncing file changes)
• Running the ec2 instance incurs an additional cost over running locally, although a t3.medium instance in Canada only costs just under 5 cents/hour

How it works: two processes are run, a sync and a tunnel process.

• The sync process keeps local and remote files in sync so that the docker process run remotely can use docker volumes transparently
• The tunnel process forwards ports needed so your local system can communicate with docker, plus additional ports as required, such as port 443 for browser communication

Setup

1. First login to your AWS account and create access keys to access AWS through the CLI

   You will need the following IAM policies:

   • AmazonEC2FullAccess
   • AWSCloudFormationFullAccess

   And now in your terminal:

   # Replace dav with your name
   # You will need to setup an AWS account if you don't have one
   # and create access key credentials
   
   aws configure --profile dav
   export AWS_PROFILE=dav

2. Install pre-requisites

   Have Homebrew (Available on both macOS and Linux now!)

   Have pipx

   pip install perry-the-docker-agent
   # or.... if part of a project
   poetry add perry-the-docker-agent
   
   # Install unison sync utility
   brew install unison
   
   # Install file-watcher driver for unison
   # On MacOS:
   brew install autozimu/homebrew-formulas/unison-fsmonitor
   
   # Or, on Linux since the above formula doesn't work:
   brew install eugenmayer/dockersync/unox

3. Generate and upload a keypair to AWS

   perry create-key-pair

4. Create the ec2 instance

   perry create

Daily Running

1. Start the remote-docker ec2 instance

   perry start

   This will automatically switch the docker context for you. If you want to switch back to the default agent run docker context use default

2. In one terminal start the tunnel so that the ports you need to connect to are exposed

   perry tunnel

3. In another terminal sync file changes to the remote instance:

   perry sync

4. Develop and code! All services should be accessible and usable as usual (eg: docker ps, docker-compose up, etc.) as long as you are running perry tunnel and are forwarding the ports you need

5. When you're done for the day don't forget to stop the instance to save money:

   perry stop

Config File

Looks for a config file at the path ./perry_config.yml by default, which can be overriden by passing --config-path.

An example perry_config.yml file:

aws_region: af-south-1
instance_type: t3.large
volume_size: 100
sync_dir: ./
project_id: "ranger"
ignore_dirs:
  - .venv
  - .git
  - node_modules
  - __pycache__
remote_port_forwards:
  local-webpack-app:
    "8080": "8080"
local_port_forwards:
  user-api:
    "2020": "2020"
  blog-api:
    "3030": "3030"

 Usage: perry [OPTIONS] COMMAND [ARGS]...                                                  
                                                                                           
╭─ Options ───────────────────────────────────────────────────────────────────────────────╮
│ --config-path               TEXT  Path of the perry config                              │
│                                   [default: ./perry_config.yml]                         │
│ --install-completion              Install completion for the current shell.             │
│ --show-completion                 Show completion for the current shell, to copy it or  │
│                                   customize the installation.                           │
│ --help                            Show this message and exit.                           │
╰─────────────────────────────────────────────────────────────────────────────────────────╯
╭─ Commands ──────────────────────────────────────────────────────────────────────────────╮
│ create           Provision a new ec2 instance to use as the remote agent                │
│ create-key-pair  Create and upload a new keypair to AWS for SSH access                  │
│ delete           Delete the provisioned ec2 instance                                    │
│ ssh              Connect to the remote agent via SSH                                    │
│ start            Start the remote agent instance                                        │
│ stop             Stop the remote agent instance                                         │
│ sync             Sync the given directories with the remote instance                    │
│ test             Test new config                                                        │
│ tunnel           Create a SSH tunnel to the remote instance to connect with the docker  │
│                  agent and containers                                                   │
╰─────────────────────────────────────────────────────────────────────────────────────────╯

The current configurable values can be seen in config.py

aws_region (takes precedence over AWS_REGION and .aws/config)

• The region to create the instance in

instance_type

• Type of ec2 instance, defaults to: t3.medium

project_id

• defaults to None
• Used to uniquely identify the instance, this is useful if multiple remote-docker agents will be created in the same AWS account

key_path

• defaults to: ~/.ssh/id_rsa_perry_{{project_id}}

local_port_forwards

• defaults to: {}
• Object containing label -> port mapping objects for opening the ports on the remote host. A mapping of "remote_port_forwards": {"my_app": {"80": "8080"}} will open port 80 on your local machine and point it to port 8080 of the remote-docker instance (which ostensibly a container is listening on). The name doesn't do anything except help legibility.

remote_port_forwards

• defaults to: {}

• Similar to local_port_forwards except will open the port on the remote instance.

  This is useful to have frontend webpack apps accessible on the remote host

ignore_dirs

• defaults to: []
• list of directories to ignore

sync_dir

• directory to sync, will usually be the root fo the project

volume_size

• defaults to: 30 (GB)
• Size of the ec2 volume.

Cost

A t3.medium instance on ca-central-1 currently costs $0.046 /hour. See current prices

Nothing else used should incur any cost with reasonable usage

Notes

• See perry --help for more information on the commands available
• The unison version running on the server and running locally have to match. If one of them updates to a newer version, you should update the other.

Perry improvements on remote-docker-aws

• Perry is configured to the project by a local perry_config.yml
• Perry uses poetry, pydantic and typer
• Perry enables swap accounting on the remote ec2 instance which allows docker-compose resource limits
• Perry uses a simpler method to sync and ignore directories.