dwellir-harvester 0.0.1

Collector framework to collect data from running Dwellir server nodes.

Dwellir Harvester

An extensible Python tool to collect metadata from local blockchain nodes and output a JSON file that conforms to a shared JSON Schema.

All timestamps use RFC 3339 / ISO 8601 with timezone.

System Requirements

• Python 3.9 or higher
• Systemd (for running as a service)

Installation

From Source

1. Clone the repository:

   git clone https://github.com/your-org/dwellir-harvester.git
   cd dwellir-harvester
   

2. Create and activate a virtual environment:

   python3 -m venv .venv
   source .venv/bin/activate  # On Windows: .venv\Scripts\activate
   

3. Install the package in development mode:

   pip install -e .
   

System-wide Installation

For production use, you can install the package system-wide:

sudo pip install .

Quick Start

Run a Single Collection

# Run with the safe default "host" collector (basic system information)
dwellir-harvester collect host null --output out.json

Run the Daemon

The harvester can run as a daemon that periodically collects data and serves it via HTTP:

# Start the daemon (runs in foreground)
dwellir-harvester-daemon

By default, the daemon:

• Runs on 0.0.0.0:18080
• Collects data every 5 minutes
• Uses the "host" collector
• Validates output against the schema

Configuration

Command Line Arguments

usage: dwellir-harvester-daemon [-h] [--collectors COLLECTORS [COLLECTORS ...]] [--host HOST] [--port PORT] [--debug]
                               [--interval INTERVAL] [--schema SCHEMA] [--no-validate] [--log-level {DEBUG,INFO,WARNING,ERROR,CRITICAL}]

Dwellir Harvester Daemon

options:
  -h, --help            show this help message and exit
  --collectors COLLECTORS [COLLECTORS ...]
                        List of collectors to run (default: ['host'])
  --host HOST           Host to bind the HTTP server to (default: 0.0.0.0)
  --port PORT           Port to run the HTTP server on (default: 18080)
  --interval INTERVAL   Collection interval in seconds (default: 300)
  --schema SCHEMA       Path to JSON schema file (defaults to bundled schema)
  --no-validate         Disable schema validation
  --debug               Enable debug logging
  --log-level {DEBUG,INFO,WARNING,ERROR,CRITICAL}
                        Logging level (default: INFO)

Environment Variables

• DATA_DIR: Directory to store data files (default: /var/lib/dwellir-harvester)
• LOG_LEVEL: Logging level (default: INFO)
• PORT: HTTP server port (default: 18080)
• INTERVAL: Collection interval in seconds (default: 300)
• COLLECTORS: Space-separated list of collectors to run (default: host)
• VALIDATE: Enable/disable schema validation (default: true)
• DEBUG: Enable debug logging (default: false)

Running as a Systemd Service

1. Install the service using the provided script:

   sudo scripts/install-service.sh
   

2. The service will be installed with default settings. You can customize it by editing:

   sudo nano /etc/dwellir-harvester/config
   

3. Start and enable the service:

   sudo systemctl start dwellir-harvester
   sudo systemctl enable dwellir-harvester
   

4. Check the status:

   systemctl status dwellir-harvester
   

5. View logs:

   journalctl -u dwellir-harvester -f
   

Available Collectors

• host - Collects basic system information (default)
• null - A dummy collector
• dummychain - Collects data from a dummychain (snap install dummychain --edge)

API Endpoints

• GET /metadata - Get the latest collected data
• GET /healthz - Health check endpoint

Development

Setting Up for Development

1. Clone the repository and install development dependencies:

   git clone https://github.com/your-org/dwellir-harvester.git
   cd dwellir-harvester
   python -m venv .venv
   source .venv/bin/activate
   pip install -e ".[dev]"
   

2. Run tests:

   pytest
   

3. Run linters:

   black .
   isort .
   mypy .
   

Adding a New Collector

1. Create a new Python file in src/dwellir_harvester/collectors/
2. Implement a class using the Dummycollector BlockchainCollector or Nullcollector GenericCollector
3. Add it to __all__ in collectors/__init__.py

License

MIT

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HTTP API

The daemon exposes a small HTTP API on 0.0.0.0:<service.port> (default :18080).

Endpoints

• GET /healthz → plain text "ok" if the daemon is serving.
• GET /metadata → the latest JSON document (200) or {"error":"metadata not found"} (404).

curl examples

# Health
curl -s http://127.0.0.1:18080/healthz

# Current metadata (pretty-print)
curl -s http://127.0.0.1:18080/metadata | jq .

If you changed the port via service.port, replace 18080 in the examples.

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Testing

python -m pip install -e .
pip install pytest
pytest -q

Build & publish (Python package)

# build
python3 -m pip install build twine
python3 -m build  # creates dist/*.tar.gz and dist/*.whl

# upload to TestPyPI first (recommended)
python3 -m twine upload -r testpypi dist/*

# Install from testpypi
python3 -m venv .venv
source .venv/bin/activate
# Pull in deps from real, this is needed only on testpypi 
pip3 install jsonschema>=4.25.1 psutil>=7.1.3 requests>=2.32.5
# Install from testpypi
pip3 install --index-url https://test.pypi.org/simple/ --no-deps dwellir-harvester

# then to PyPI
python3 -m twine upload dist/*

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Notes

• The framework fills metadata.last_collect_attempt_at, metadata.last_collect_status, and metadata.last_successful_collect_at automatically.
• Collectors should only return the blockchain and workload portions.
• For recoverable issues, raise CollectorPartialError with warnings; the run will be marked partial and still emit output.
• For unrecoverable issues, raise CollectorFailedError.
• The null collector is intended for smoke tests, CI, and “no local client” deployments.