EOS Yield Contract

This contract demostrates how an EOS contract can be made immutable in a given period of time, without losing mutability forever. Such a mechanism guarantees immutability when trustlessness is necessary, with code changes possible with prior notice to users.

The intent of this contract is explained in this reddit post.

Powered by EOS Yield

The following dApps feature implementation of the Temporary Immutability pattern proposed by this contract:

• Final Noob: A decentralized EOS game.

• DeltaDex: A fully on-chain decentralized exchange.

Clone and Compile

To clone the repository and compile the contract into binary:

$ git clone https://github.com/xJonathanLEI/eosyield.git
$ cd eosyield
$ eosiocpp -o eosyield.wast eosyield.cpp
$ eosiocpp -g eosyield.abi eosyield.cpp

Three files: eosyield.wast, eosyield.wasm and eosyield.abi will be generated after compilation succeeds.

Contract Setup

To test the contract, first set up a contract account, say yield:

$ cleos system newaccount --buy-ram "1000.0000 SYS" --stake-net "100.0000 SYS" --stake-cpu "100.0000 SYS" eosio yield YOUR_PUBLIC_KEY;

Publish the contract:

$ cleos set contract yield /path/to/contract/folder;

Give account owner permission to eosio.code permission so that the contract itself can modify its own permission settings:

$ cleos set account permission yield owner '{"threshold": 1,"keys": [{"key": "YOUR_PUBLIC_KEY","weight": 1}],"accounts": [{"permission":{"actor":"yield","permission":"eosio.code"},"weight":1}]}' -p yield@owner;

Set the owner to be your account (jonathan here):

$ cleos push action yield setowner '["jonathan"]' -p yield@owner;

To yield control on the contract:

$ cleos push action yield yieldcontrol '[60]' -p jonathan;

If you check permission now, you would see the contract code would be the sole owner of itself:

$ cleos get account yield;

Check the yield info from database:

$ cleos get table yield yield yieldinfo;

To extend the yield period:

$ cleos push action yield extend '[120]' -p jonathan;

To regain control after the expiration is reached:

$ cleos push action yield regain '' -p jonathan;

License

This EOS contract is licensed under the MIT license.