ykim-1 / py-metadata

A Python package for interacting with the Linode Metadata Service.

Linode Metadata Client for Python

This package allows Python projects to easily interact with the Linode Metadata Service.

Getting Started

Prerequisites

• Python >= 3.8
• A running Linode Instance

Installation

pip install linode-metadata

Building from Source

To build and install this package:

• Clone this repository
• make install

Examples

The following code snippets show multiple different ways to use the metadata client and retrieves various metadata of the current Linode.

Basic Usage

from linode_metadata import MetadataClient

client = MetadataClient()

instance_info = client.get_instance()
network_info = client.get_network()
ssh_info = client.get_ssh_keys()
user_data = client.get_user_data()

print("Instance ID:", instance_info.id)
print("Public IPv4:", network_info.ipv4.public[0])
print("SSH Keys:", "; ".join(ssh_info.users))
print("User Data:", user_data)

Asynchronous I/O and Context Manager Support

You can also use the context manager to ensure the HTTP client will be properly closed, and the asyncio enabled client is also available.

import asyncio
from linode_metadata import AsyncMetadataClient

async def get_metadata():
    with AsyncMetadataClient() as client:
        instance_info = await client.get_instance()
        print("Instance ID:", instance_info.id)

asyncio.run(get_metadata())

Watchers

Watchers are useful for monitor changes in the metadata, e.g. newly added IP address to the Linode.

import asyncio
from linode_metadata import AsyncMetadataClient

async def get_metadata():
    async with AsyncMetadataClient() as client:
        watcher = client.get_watcher()
        async for new_network_info in watcher.watch_network():
            print(new_network_info)

asyncio.run(get_metadata())

Testing

Before running tests on this project, please ensure you have a Linode Personal Access Token exported under the LINODE_TOKEN environment variable.

End-to-End Testing Using Ansible

This project contains an Ansible playbook to automatically deploy the necessary infrastructure and run end-to-end tests on it.

To install the dependencies for this playbook, ensure you have Python 3 installed and run the following:

make test-deps

After all dependencies have been installed, you can run the end-to-end test suite by running the following:

make int-test

If your local SSH public key is stored in a location other than ~/.ssh/id_rsa.pub, you may need to override the TEST_PUBKEY argument:

make TEST_PUBKEY=/path/to/my/pubkey int-test

NOTE: To speed up subsequent test runs, the infrastructure provisioned for testing will persist after the test run is complete. This infrastructure is safe to manually remove.

Manual End-to-End Testing

End-to-end tests can also be manually run using the make int-test-local target. This test suite is expected to run from within a Linode instance and will likely fail in other environments.

License

This software is Copyright Akamai Technologies, Inc. and is released under the Apache 2.0 license.