Atuin

Atuin is the name of the codename of the Turtle Empire project. Atuin seeks to create a self-sustaining and autonomous community of Minecraft turtles and computers.

The overall structure of the system is centralized. A central manager has an internal world representation that is continuously updated as turtles perform side-effects on the world. The central manager runs planning algorithm on the current world state to determine which action needs to be performed next. An idle turtle is selected to perform the action.

In practice, the software loaded onto each individual turtle is minimal. In their idle state, turtles issue a request for work to the central computer. This request blocks until the central computer finds work for the turtle. The work is transferred to the turtle as a string representation of a Lua program that is executed by the turtle.

The central manager generates Lua programs by using a template-based system. In the future, an EDSL may be developed to create more sophisticated Lua programs.

TPut

The Atuin server provides functionality that is a strict superset of the functionality of TPut, from which it is forked. That being said, files can be uploaded and downloaded from the Atuin server using POST and GET requests under the files route.

Setup

You know the drill:

1. cabal sandbox init
2. cabal install --only-dependencies
3. cabal build

To use the tput subsystem of the Atuin server, an uploads directory is required.

1. mkdir data
2. cabal run data

The service listens on port 8080.

If you don't like this:

• then change the code to use a different port
• send a pull request with something to use environment variables

Usage

These are the available endpoints for the TPut subsystem.

• GET /files/:path retrieves the contents of path or 404s.
• POST /files/:path creates or overwrites the contents of path with the request body.
• GET /list retrieves a list of files stored on the server with one file name per line.

Servant will automatically deal with issues like malicious users injecting dots into the URL. Slashes may be used in the capture parameter in order to place files into subdirectories. However, there is currently no support for creating directories, so attempting to place a file into a subdirectory that does not exist will fail.

Ensure that the Content-Type header in your request is set to text/plain;charset=utf-8. Anything else will upset servant because I'm too lazy to make it more lenient. In particular HTTP 415 responses will be produced.

Atuin services

Messaging

Atuin provides the /msg route for sending messages between computers within minecraft by proxying the message through the Atuin server. By using this proxy scheme, we avoid the need to collect Ender Pearls, required in order to craft wireless modems. This allows communication between any two computers across arbitrary distances and even across dimensions or even across servers. Furthermore, message delivery can be delayed; the messages are recorded server-side in queue when sent, so the destination computer need not be online in order to eventually receive the message.

These are the endpoints associated with the messaging subsystem.

• GET /msg/:computerId retrieves a message destined for the given computerId.
• POST /msg/:computerId sends a message to the given computerId.

Message receiving via GET /msg/:computerId is nonblocking: if there are no available messages for computerId, the then server will produce a response with no body. Consequently, sending empty strings is not possible. We have found that sending empty strings is not useful enough for this to be a problem.

Blockdata

The blockdata endpoint is used to signal new information about a block to the central server.

Every time a turtle moves, it should intelligently inspect up, down, and forward to determine the type of blocks around it and send this information to the central server. This information is used to update the central server's internal world representation.

• POST /blockdata updates the information about the block at a given position in the internal world representation.

  Required query string parameters:

  • at: type int, format comma-separated.