Swiss Train Tracker on Stellar Blockchain

Learn how to store real-world data on the blockchain by tracking the journeys of the IR36 train from Basel to Zürich HB. The project provides transparent, immutable, and decentralized record of the train's journeys, offering real-time data that can be verified by anyone. This repository contains an example application from the How To Build Oracles with Soroban screencast.

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Usage

To check the current journey details for the train IR36 on the blockchain, run the following command:

stellar contract invoke --id CDVCACHHWJJDBNJOJHPHZDKJV3PRFMT6HDM52AF3RBTW2LG3ERIOXNO2 --source <<YOUR ACCOUNT NAME>> --network testnet -- get_journey | jq

You need to setup Stellar CLI before using this command. To do so, just follow instructions in docs.

Result:

{
  "current_stop": 1,
  "journey_ref": "63683a313a736a7969643a3130303030313a313937352d303031",
  "journey_status": 2,
  "stop_arrivals": [
    1723551060,
    1723551900,
    18446744073709551615,
    18446744073709551615,
    18446744073709551615,
    18446744073709551615,
    18446744073709551615
  ],
  "stop_refs": [
    8500010,
    8500301,
    8500320,
    8500305,
    8500309,
    8503504,
    8503000
  ],
  "stop_timetable": [
    1723551090000,
    1723551840000,
    1723552440000,
    1723552860000,
    1723553820000,
    1723554420000,
    1723555428000
  ]
}

How to Run?

Before you start following this guide you must configure Stellar CLI.

Deploy the contract

Run tests to ensure everything is set up correctly:

cargo test

You should see output similar to this:

   Compiling swiss-train-manager v0.0.1 (.../contracts/swiss_trains_manager)
    Finished `test` profile [unoptimized + debuginfo] target(s) in 3.65s
     Running unittests src/lib.rs (target/debug/deps/swiss_train_manager-8f83991ea2f22bb8)

running 4 tests
test test::test_initialize_contract ... ok
test test::test_get_journey ... ok
test test::test_schedule_journey ... ok
test test::test_check_in ... ok

test result: ok. 4 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.13s

1. Build the contract:

stellar contract build

3. Deploy the contract to the testnet:

stellar contract deploy --wasm target/wasm32-unknown-unknown/release/swiss_train_manager.wasm --source <<YOUR ACCOUNT NAME>> --network testnet
# CDVCACHHWJJDBNJOJHPHZDKJV3PRFMT6HDM52AF3RBTW2LG3ERIOXNO2

Congrats! You deployed you first smart contract!

4. Store contract ID in oracle/.env file:

echo "CONTRACT_ID=CDVCACHHWJJDBNJOJHPHZDKJV3PRFMT6HDM52AF3RBTW2LG3ERIOXNO2" >> ./oracle/.env

5. Create Operator (oracle's) account

stellar keys generate --global operator --network testnet

6. Export Operator wallet keys

echo "OPERATOR_PRIVATE_KEY=$(stellar keys show operator)" >> ./oracle/.env

7. Nominate contract Operator

Retrieve Operator public address

stellar keys address operator
// GCS4KEVYH5AMDNCPDYKKWFSJNRK4CBUPZIIO6FNFEK3NWTDJX6N26MW5

Call the init method reponsible of setting contract's operator

stellar contract invoke --id CDVCACHHWJJDBNJOJHPHZDKJV3PRFMT6HDM52AF3RBTW2LG3ERIOXNO2 --source mateusz --network testnet -- init --operator <<OPERATOR ACCOUNT PUBLIC KEY>>

8. Try to invoke contract

stellar contract invoke --id CDVCACHHWJJDBNJOJHPHZDKJV3PRFMT6HDM52AF3RBTW2LG3ERIOXNO2 --source operator --network testnet -- get_journey | jq

If you see output similar to this it means your contract is working:

{
  "current_stop": 4294967295,
  "journey_ref": "63683a313a736a7969643a3130303030313a313937352d303031",
  "journey_status": 0,
  "stop_arrivals": [],
  "stop_refs": [],
  "stop_timetable": []
}

Run Oracle

Once you have your smart contract setup, you can run Oracle and write first data to blockchain.

1. Setup project

Navigate to the oracle/ directory and install dependencies:

cd oracle
npm i

2. Start the Oracle:

npm start

Acknowledgments

• Open data platform mobility Switzerland for making the train journey data available and providing OJP-SDK.
• Stellar Development Foundation for providing the tools and infrastructure.
• This project competes in Build Better on Stellar: Smart Contract Challenge.