Initial commit: smart contract templates for bash, go, python, and typescript

This commit is contained in:
2026-03-17 19:59:47 -04:00
commit 0634e66469
35 changed files with 3794 additions and 0 deletions

243
bash/README.md Normal file
View File

@@ -0,0 +1,243 @@
# Bash Smart Contract Template
A Bash-based smart contract client for Dragonchain Prime that connects via gRPC.
This template uses a thin Python gRPC infrastructure layer to handle the network protocol, while your smart contract logic lives entirely in `process.sh`.
## Prerequisites
- Bash 4.0+
- Python 3.10+ (for gRPC infrastructure)
- pip
- jq (for JSON processing in bash)
## Quick Start
1. **Copy this template** to create your smart contract:
```bash
cp -r bash /path/to/my-smart-contract
cd /path/to/my-smart-contract
```
2. **Set up the environment**:
```bash
make setup
source venv/bin/activate
```
Or without make:
```bash
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
```
3. **Generate the protobuf code**:
```bash
make proto
```
4. **Configure your connection** by editing `config.yaml`:
```yaml
server_address: "your-dragonchain-server:50051"
smart_contract_id: "your-smart-contract-id"
api_key: "your-api-key"
```
5. **Implement your smart contract logic** in `process.sh`.
6. **Run**:
```bash
python main.py --config config.yaml
```
## Configuration
| Field | Description | Default |
|-------|-------------|---------|
| `server_address` | gRPC server address | Required |
| `smart_contract_id` | Your smart contract ID | Required |
| `api_key` | API key for authentication | Required |
| `use_tls` | Enable TLS encryption | `false` |
| `tls_cert_path` | Path to TLS certificate | - |
| `num_workers` | Concurrent transaction processors | `10` |
| `reconnect_delay_seconds` | Delay between reconnection attempts | `5` |
| `max_reconnect_attempts` | Max reconnect attempts (0 = infinite) | `0` |
## Implementing Your Smart Contract
Edit `process.sh`. The script receives the transaction JSON as its first argument (`$1`) and must output a JSON result to stdout.
### Interface
**Input:**
- `$1` - Transaction JSON string
- Environment variables - Server env vars and secrets are exported
**Output (stdout):**
```json
{
"data": { "your": "result" },
"output_to_chain": true,
"error": ""
}
```
**Logs (stderr):** Anything written to stderr is captured and returned as logs.
**Exit code:** 0 = success, non-zero = error (stderr used as error message).
### Example
```bash
#!/usr/bin/env bash
set -euo pipefail
TX_JSON="$1"
# Parse transaction fields with jq
TXN_ID=$(echo "$TX_JSON" | jq -r '.header.txn_id')
TXN_TYPE=$(echo "$TX_JSON" | jq -r '.header.txn_type')
PAYLOAD=$(echo "$TX_JSON" | jq -c '.payload')
# Access environment variables
SC_NAME="${SMART_CONTRACT_NAME:-}"
DC_ID="${DRAGONCHAIN_ID:-}"
# Access secrets
MY_SECRET="${SC_SECRET_MY_SECRET:-}"
# Log to stderr
echo "Processing transaction $TXN_ID" >&2
# Process based on payload action
ACTION=$(echo "$TX_JSON" | jq -r '.payload.action // empty')
case "$ACTION" in
create)
RESULT='{"status": "created"}'
;;
update)
RESULT='{"status": "updated"}'
;;
*)
RESULT='{"status": "unknown"}'
;;
esac
# Output result as JSON
jq -n --argjson result "$RESULT" '{
"data": $result,
"output_to_chain": true,
"error": ""
}'
```
### Transaction Structure
The transaction JSON passed to your script has this format:
```json
{
"version": "1",
"header": {
"tag": "my-tag",
"dc_id": "dragonchain-id",
"txn_id": "transaction-id",
"block_id": "block-id",
"txn_type": "my-type",
"timestamp": "2024-01-01T00:00:00Z",
"invoker": "user-id"
},
"payload": {
"your": "custom data"
}
}
```
### Available Environment Variables
| Variable | Description |
|----------|-------------|
| `TZ` | Timezone |
| `ENVIRONMENT` | Deployment environment |
| `INTERNAL_ID` | Internal identifier |
| `DRAGONCHAIN_ID` | Dragonchain ID |
| `DRAGONCHAIN_ENDPOINT` | Dragonchain API endpoint |
| `SMART_CONTRACT_ID` | This smart contract's ID |
| `SMART_CONTRACT_NAME` | This smart contract's name |
| `SC_ENV_*` | Custom environment variables |
### Secrets
Secrets are exported as environment variables with keys prefixed by `SC_SECRET_`.
## Project Structure
```
.
├── main.py # gRPC infrastructure (do not modify)
├── process.sh # Your smart contract logic (modify this)
├── proto/
│ └── remote_sc.proto # gRPC service definition
├── config.yaml # Configuration file
├── requirements.txt # Python dependencies (for infrastructure)
├── Makefile # Build commands
└── README.md # This file
```
### File Descriptions
- **`process.sh`** - Your smart contract logic. This is the only file you need to modify for most use cases.
- **`main.py`** - gRPC client infrastructure that invokes `process.sh` for each transaction. You typically don't need to modify this file.
## Make Commands
```bash
make setup # Create venv and install dependencies
make proto # Generate Python code from proto files
make run # Run with default config
make test # Syntax check and sample run of process.sh
make clean # Remove generated files and venv
make deps # Install dependencies (no venv)
make check # Verify required tools (python3, bash, jq)
make format # Format process.sh with shfmt (if installed)
```
## Concurrent Processing
The client uses a thread pool to process multiple transactions concurrently. Each worker invokes a separate instance of `process.sh`. The number of workers is configurable via `num_workers` in the config file.
## Error Handling
- Return errors by setting the `error` field in your JSON output, or exit with a non-zero code
- Anything written to stderr is captured as logs
- The client automatically handles reconnection on connection failures
## Docker
Example `Dockerfile`:
```dockerfile
FROM python:3.11-slim
RUN apt-get update && apt-get install -y --no-install-recommends jq bash && rm -rf /var/lib/apt/lists/*
WORKDIR /app
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
COPY . .
RUN chmod +x process.sh
RUN python -m grpc_tools.protoc \
-I./proto \
--python_out=. \
--grpc_python_out=. \
proto/remote_sc.proto
CMD ["python", "main.py", "--config", "config.yaml"]
```
## License
[Your License Here]