HCloud

Unofficial Ruby integration with the Hetzner Cloud API.

Installation

Add this line to your application's Gemfile:

gem "hetznercloud"

And then execute:

$ bundle install

Or install it yourself as:

$ gem install hcloud

Usage

require "hcloud"

# Create a new client
client = HCloud::Client.new(access_token: "my_access_token")

# Set client as default connection
HCloud::Client.connection = client

# Create resource
ssh_key = HCloud::SSHKey.new(name: "My SSH key", public_key: "ssh-rsa ...")
ssh_key.create

# Alternate syntax:
ssh_key = HCloud::SSHKey.create(name: "My SSH key", public_key: "ssh-rsa ...")

# Find resource by ID
ssh_key = HCloud::SSHKey.find(1)

# Update resource
ssh_key.updatable_attributes # => [:name, :labels]
ssh_key.name = "New name"
ssh_key.update

# Delete resource
ssh_key.delete
ssh_key.deleted?
# => true

# For detailed usage of resources, refer to the class documentation

# When specifying associated resources, you can either use an instance of the resource, an integer as ID or a string as name.
# The following calls are equivalent:
server = HCloud::Server.new(name: "my_server", location: "fsn", ...)
server = HCloud::Server.new(name: "my_server", location: 1, ...)
server = HCloud::Server.new(name: "my_server", location: Location.new(name: "fsn"), ...)

The gem aims to provide a simple, object-oriented interface to the Hetzner Cloud API. It does not aim to be an authoritative source of information, and as such does little validation on your input data or behaviour. It expects you to use it in a sane way.

Features

The following table lists the Hetzner Cloud API endpoints that are currently implemented.

Resource	State
Actions	Implemented
Certificates	Implemented
Certificate Actions	Implemented
Datacenters	Implemented
Firewalls	Implemented
Firewall Actions	Implemented
Floating IPs	Implemented
Floating IP Actions	Implemented
Images	Implemented
Image Actions	Implemented
ISOs	Implemented
Load Balancers	Implemented
Load Balancer Actions	Implemented
Load Balancer Types	Implemented
Locations	Implemented
Primary IPs	Implemented
Primary IP Actions	Implemented
Networks	Implemented
Network Actions	Implemented
Placement Groups	Implemented
Pricing	Implemented
Servers	Partially implemented
Server Actions	Not implemented
Server Types	Implemented
SSH Keys	Implemented
Volumes	Implemented
Volume Actions	Implemented
Metadata	Implemented

Pagination

Paginated resources are wrapped in a HCloud::Collection that automatically fetches the next page when needed. The collection acts as a (lazy) enumerator. Call to_a to fetch all pages and parse all resources.

Rate limiting

From the documentation:

The default limit is 3600 requests per hour and per Project. The number of remaining requests increases gradually. For example, when your limit is 3600 requests per hour, the number of remaining requests will increase by 1 every second.

The client is able to handle the rate limiting by delaying the requests if necessary and executing them whenever possible. To enable this behaviour, pass rate_limit: true as argument to HCloud::Client.new. Client calls will block until possible to execute and then return.

client = HCloud::Client.new(access_token: "my_token", rate_limit: true)

# At least one request has to be made to enable the rate limiter
client.rate_limiter.limit # => nil
client.rate_limiter.remaining # => nil
client.rate_limiter.reset # => nil

HCloud::Server.create(...)

client.rate_limiter.limit # => 3600
client.rate_limiter.remaining # => 3599
client.rate_limiter.reset # => 2023-01-01 00:00:00 +0100

# Make a bunch of requests

client.rate_limiter.remaining # => 0

servers = HCloud::Server.all # Will block until remaining requests have regenerated (1 second by default) and then execute
ssh_keys = HCloud::SSHKey.all # Will block until remaining requests have regenerated (1 second by default) and then execute

Since rate limits are per hour and per project, using multiple clients at the same time will interfere with the rate limiting mechanism. To prevent this, wrap client calls in a loop that retries the call after it fails with a HCloud::RateLimitExceeded error.

Testing

# Run test suite (without integration tests)
bundle exec rspec

# Run integration tests (WARNING: THIS WILL DESTROY **ALL** RESOURCES AFTER EACH RUN)
bundle exec rspec --tag integration

Debugging

Logging

When using the gem in your code, you can pass a logger: argument to HCloud::Client:

logger = Logger.new("log/http.log")
logger.level = :debug

client = HCloud::Client.new(access_token: "my_access_token", logger: logger)

When executing the test suite, set LOG_LEVEL environment variable to debug in order to see HTTP requests.

Endpoint

HCloud::Client also accepts an alternate endpoint:

client = HCloud::Client.new(access_token: "my_access_token", endpoint: "https://myproxy/v1")

Releasing

To release a new version, update the version number in lib/hcloud/version.rb, update the changelog, commit the files and create a git tag starting with v, and push it to the repository. Github Actions will automatically run the test suite, build the .gem file and push it to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/floriandejonckheere/hcloud.

License

The gem is available as open source under the terms of the MIT License.