Soroban Hackaton Parent Control Allowance

The focus of this smart contract is a parent account (admin) allows users (children) to allowance a specific amount in a specific range of time according to a step period.

The Parent set the children and the amount to each one. The children can withdraw according to the amount allowed.

Main functions

initialize

Sets the initial contract configuration, specifying the admin, the token contract id, start and end times, and the step between increments of the allowance amounts.

set_allow

Sets the AccountID of the child account and the incremental amount of the allowance per step. It's possible to set more than one child account.

withdraw

Allows the AccountID (child) to withdraw a desired amount. The function then checks for the availability of the specified amount. For the allowance to be available, the withdraw function must be called between the start and end periods. In order to realize the transfer operation, the external token contract is callled, invoking its xfer_from function.

Auxiliar functions

get_allow

Gets the per step allowance increment of a given child.

get_wthdr

Get the amount of allowance already withdrawn by a given child account.

get_aval

Gets the amount of allowance available for a given child account.

get_start

Gets the start period.

get_end

Gets the end period.

get_step

Get the step period between increments of the allowances.

Step by step to run the contract

1. Build the wasm

cargo build --target wasm32-unknown-unknown --release

2. Run the future net node

docker run --rm -it \
  --platform linux/amd64 \
  -p 8000:8000 \
  --name stellar \
  stellar/quickstart:soroban-dev@sha256:8046391718f8e58b2b88b9c379abda3587bb874689fa09b2ed4871a764ebda27 \
  --futurenet \
  --enable-soroban-rpc

3. Make sure it's running with a core_latest_ledger larger than 0

curl http://localhost:8000

4. Generate key pair

Public Key	GDT3C2AAQUXC2Y3V6HFVG3BXWG3P6OGTYLJTNI7YED6AU6NZLW2AOQY3
Secret Key	SB3O7LX4CJO4Z2WCT7RZQ7RZTFUPDV6COAAO4E3LMPQ32NM24G3D72D2

5. Fund the wallet

curl "https://friendbot-futurenet.stellar.org/?addr=G..."
curl "https://friendbot-futurenet.stellar.org/?addr=GDT3C2AAQUXC2Y3V6HFVG3BXWG3P6OGTYLJTNI7YED6AU6NZLW2AOQY3"

6. Deploy the contract

soroban deploy \
  --wasm parent_allowance.wasm \
  --secret-key SB3O7LX4CJO4Z2WCT7RZQ7RZTFUPDV6COAAO4E3LMPQ32NM24G3D72D2 \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022'

Contract ID: 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54

7. Deploy token contract

soroban deploy \
  --wasm soroban_token_contract.wasm \
  --secret-key SB3O7LX4CJO4Z2WCT7RZQ7RZTFUPDV6COAAO4E3LMPQ32NM24G3D72D2 \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022'

Contract ID: 8216da0fc28346cdd27a61819f93cc7c1488584717ba6e94a8e45a5daa084688

8. Invoke Token contract initialization

soroban invoke \
  --id 8216da0fc28346cdd27a61819f93cc7c1488584717ba6e94a8e45a5daa084688 \
  --secret-key SB3O7LX4CJO4Z2WCT7RZQ7RZTFUPDV6COAAO4E3LMPQ32NM24G3D72D2 \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn initialize \
  --arg '{"object":{"vec":[{"symbol":"Account"},{"object":{"account_id":{"public_key_type_ed25519":"e7b16800852e2d6375f1cb536c37b1b6ff38d3c2d336a3f820fc0a79b95db407"}}}]}}' \
  --arg 8 \
  --arg 44616e69656c \
  --arg 444e44

Name: Daniel
Symbol: DND

9. Create a parent account

Public Key	GBWJIH5VDCIKAVFOJK4N5RH5O7NZ27R3V6OSJGJ4JUQO5XB6U73CXYNL
Secret Key	SDVSMGYKIFR3MLUPY5FEZRKKUC6Y4GZDIYPSC4SMSALLR665POBPABFM

10. Create a child account

Public Key	GCKQ4EJVBJ5YMPVEEYFL4BWHRJZGFYTKGXVQJBTZCZKH4CM3HUQ7V6YJ
Secret Key	SAE6QSAEAT5PMA6VTMFE6RCYMIKVRMJKNESYK5NJ5W6DZ4ESLJUCEPIH

11. Establish a trusline between both accounts and the created token (DND)

• Stellar laboratory

12. Fund parent account with the created token (DND)

• Stellar laboratory

13. Increase parent account allowance

soroban invoke \
  --id 8216da0fc28346cdd27a61819f93cc7c1488584717ba6e94a8e45a5daa084688 \
  --secret-key SDVSMGYKIFR3MLUPY5FEZRKKUC6Y4GZDIYPSC4SMSALLR665POBPABFM \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn incr_allow \
  --arg '{"object":{"vec":[{"symbol":"Invoker"}]}}' \
  --arg 0 \
  --arg '{"object":{"vec":[{"symbol":"Contract"},{"object":{"bytes":"07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54"}}]}}' \
  --arg 300000

14. Invoke Parent Allowance contract initialization

soroban invoke \
  --id 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54 \
  --secret-key SDVSMGYKIFR3MLUPY5FEZRKKUC6Y4GZDIYPSC4SMSALLR665POBPABFM \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn initialize \
  --arg '{"object":{"account_id":{"public_key_type_ed25519":"6c941fb51890a054ae4ab8dec4fd77db9d7e3baf9d24993c4d20eedc3ea7f62b"}}}' \
  --arg 8216da0fc28346cdd27a61819f93cc7c1488584717ba6e94a8e45a5daa084688 \
  --arg 300 \
  --arg 0 \
  --arg 0

15. Test getStep

soroban invoke \
  --id 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54 \
  --secret-key SDVSMGYKIFR3MLUPY5FEZRKKUC6Y4GZDIYPSC4SMSALLR665POBPABFM \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn getStepP

16. Test setAllow

soroban invoke \
  --id 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54 \
  --secret-key SDVSMGYKIFR3MLUPY5FEZRKKUC6Y4GZDIYPSC4SMSALLR665POBPABFM \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn setAllow \
  --arg '{"object":{"account_id":{"public_key_type_ed25519":"950e11350a7b863ea4260abe06c78a7262e26a35eb04867916547e099b3d21fa"}}}' \
  --arg 1000

17. Test withdraw (NOT WORKING YET)

soroban invoke \
  --id 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54 \
  --secret-key SAE6QSAEAT5PMA6VTMFE6RCYMIKVRMJKNESYK5NJ5W6DZ4ESLJUCEPIH \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn withdraw \
  --arg '{"object":{"account_id":{"public_key_type_ed25519":"950e11350a7b863ea4260abe06c78a7262e26a35eb04867916547e099b3d21fa"}}}' \
  --arg 700

17. Test getWthdrwn (NOT WORKING YET)

soroban invoke \
  --id 07cc3fbe8350d9f4135b6065f3dc9599a12d58b1266223ff7cc259c429008a54 \
  --secret-key SAE6QSAEAT5PMA6VTMFE6RCYMIKVRMJKNESYK5NJ5W6DZ4ESLJUCEPIH \
  --rpc-url http://localhost:8000/soroban/rpc \
  --network-passphrase 'Test SDF Future Network ; October 2022' \
  --fn getWthdrwn \
  --arg '{"object":{"account_id":{"public_key_type_ed25519":"950e11350a7b863ea4260abe06c78a7262e26a35eb04867916547e099b3d21fa"}}}'