Muddle Run

A home for experiments for muddle.run.

muddle-run-10-07-2021.mp4

Project state

Currently, the project represents the very bare-bones of the game I'm trying to build: a multiplayer runner with a collaborative level editor, which will also allow players to test levels while they are being designed.

Current features

• WASD movement
• Rapier physics
• Netcode (poorly executed one, but inspired by Overwatch's GDC presentation)
  • Interpolation
  • Rewinding game state
  • Real-time adjustment of client simulation speed
• Initial version of Builder mode (collaborative level editor)

Roadmap

• Gameplay
• Builder Mode
• Techdebt, Performance & Stability

Building and running

This application can be run in either UPD, or WebRTC mode. The workspace contains the following binary projects:

• mr_dekstop_client
• mr_web_client
• mr_server
• mr_matchmaker
• mr_persistence

Running the desktop client and the server

# Running the server
# (Note that 127.0.0.1 might not work for Windows, you can use your local network ip instead, like 192.168.x.x)
# (See https://github.com/naia-rs/naia-socket/issues/24)
MUDDLE_PUBLIC_IP_ADDR=127.0.0.1 MUDDLE_LISTEN_PORT=3455 cargo run -p mr_server

# Running the client
cargo run -p mr_desktop_client

Running the web client and the server

# Running the server
# (Note that 127.0.0.1 might not work for Firefox, you can use your local network ip instead, like 192.168.x.x)
MUDDLE_PUBLIC_IP_ADDR=127.0.0.1 MUDDLE_LISTEN_PORT=3455 cargo run -p mr_server

# Running the client
cd bins/web_client
wasm-pack build --target web
basic-http-server . # or any other tool that can serve static files

Running the persistence service

Prerequisites:

• PostgreSQL database
• sqlx-cli
• Auth0 and Google OAuth 2.0 client credentials (see the environment variables section)

Creating a database

DATABASE_URL=postgres://postgres@localhost/mr_persistence_development sqlx database setup

Environment variables

Environment variables are read when both compiling the binaries and running them (except for the web client). The environment variables that are read during the run-time take higher priority.

Dotenv files are also supported. They are recursively searched down to the root starting from a working directory. The binaries search for the following files:

• .env
• .env.$MUDDLE_ENV
• .env.$CARGO_PKG_NAME
• .env.$CARGO_PKG_NAME.$MUDDLE_ENV

Every found file is loaded, and all read variables are merged. Priority is defined as in the list above, where the most specific dotenv file overrides the vars from the other ones.

MUDDLE_ENV equals production when compiling with the release profile and development when compiling with the debug one. It can be overridden with an environment variable.

mr_server

• MUDDLE_PUBLIC_IP_ADDR (mandatory if outside Agones cluster)
  • It can't equal to 0.0.0.0, use 127.0.0.1 if you want to connect to localhost, for instance.
  • Also, note that 127.0.0.1 might not work for Firefox, you can use your local network instead, like 192.168.x.x.
• MUDDLE_LISTEN_IP_ADDR (defaults to 0.0.0.0)
• MUDDLE_LISTEN_PORT (mandatory if outside Agones cluster)
• MUDDLE_IDLE_TIMEOUT (defaults to 300)
  • Specifies the time in milliseconds after which a server will be closed if there are no connected players.
• MUDDLE_PUBLIC_PERSISTENCE_URL (optional)
• MUDDLE_PRIVATE_PERSISTENCE_URL (optional)
• MUDDLE_GOOGLE_WEB_CLIENT_ID (mandatory if persistence urls are set)
• MUDDLE_GOOGLE_DESKTOP_CLIENT_ID (mandatory if persistence urls are set)
• MUDDLE_AUTH0_CLIENT_ID (mandatory if persistence urls are set)

mr_desktop_client and mr_web_client

• MUDDLE_SERVER_IP_ADDR (defaults to 127.0.0.1)
• MUDDLE_SERVER_PORT (defaults to 3455)
• MUDDLE_MATCHMAKER_URL (optional)
  • If this variable is passed, MUDDLE_SERVER_IP_ADDR and MUDDLE_SERVER_PORT are still read, but the server is displayed in the list only if MUDDLE_SERVER_IP_ADDR is passed explicitly (the default value is ignored).
• MUDDLE_PUBLIC_PERSISTENCE_URL (mandatory if MUDDLE_MATCHMAKER_URL is set)
• MUDDLE_GOOGLE_CLIENT_ID (mandatory if MUDDLE_MATCHMAKER_URL is set)
• MUDDLE_GOOGLE_CLIENT_SECRET (mandatory for the desktop client if MUDDLE_MATCHMAKER_URL is set)
  • Google only considers Desktop clients as public ones, also requiring client secrets in the requests. Don't set the secret for the web clients.
• MUDDLE_AUTH0_CLIENT_ID (mandatory if MUDDLE_MATCHMAKER_URL is set)

Both client and server

• SIMULATIONS_PER_SECOND (defaults to 120, compile-time only)
  • Is expected to work with the following values: 30, 60, 120. You may want to set a lower value than the default one if your device can't handle 120 simulations per second.
  • Note that both the server and the client must be compiled with the same value.

mr_persistence

• MUDDLE_GOOGLE_WEB_CLIENT_ID (mandatory)
• MUDDLE_GOOGLE_DESKTOP_CLIENT_ID (mandatory)
• MUDDLE_AUTH0_CLIENT_ID (mandatory)

Building docker images

mr_matchmaker

docker build -t mvlabat/mr_matchmaker -f mr_matchmaker.dockerfile . --platform linux/amd64

mr_web_client

docker build -t mvlabat/mr_web_client --build-arg muddle_matchmaker_ip_addr=<IP> --build-arg muddle_matchmaker_port=<PORT> -f mr_web_client.dockerfile .  --platform linux/amd64

mr_server

docker build -t mvlabat/mr_server -f mr_server.dockerfile . --platform linux/amd64

DevOps

Prerequisites

• aws-cli (tested with 2.9.12)
  • Make sure to configure AWS CLI: aws configure
• kubectl (v1.23.0)
• helm (tested with v3.10.3)

Applying

1. terraform apply -target=module.eks_cluster
2. aws eks --region <region-code> update-kubeconfig --name <cluster_name>
3. terraform apply -target=module.helm_agones
   • Resources declared with kubernetes_manifest fail to plan without this helm release installed first
4. terraform apply

Destroying

• terraform destroy -target=module.agones
• helm delete agones -n agones-system && terraform destroy -target=module.helm_agones
• terraform destroy -target=module.eks_cluster

Updating deployment

kubectl set image deployment <DEPLOYMENT_NAME> <CONTAINER_NAME>=<TAG>

For example:

• kubectl set image deployment mr-matchmaker mr-matchmaker=mvlabat/mr_matchmaker
  • You can also alternate appending and removing :latest tag suffix, to trick kubernetes into redeploying (otherwise it might think that the image is the same and won't pull its updated version).

Troubleshooting

• Error: Kubernetes cluster unreachable: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable

  To fix this error, run export KUBE_CONFIG_PATH=~/.kube/config (or add it to your shell rc).

  • Also, make sure you ran aws eks --region <region-code> update-kubeconfig --name <cluster_name> before.