What is an OpenStack API? Definition, structure & benefits

Automation plays a central role in the modern cloud world. Companies and developers are increasingly using platforms such as OpenStack to manage flexible and scalable cloud infrastructures. But how do applications actually communicate with this platform? The answer lies in the OpenStack API — the key that gives developers direct access to cloud resources.

In this article, you'll learn what the OpenStack API is, how it works, what benefits it offers, and why it's so important for modern software and app development.

What is OpenStack?

OpenStack is an open-source cloud platform that allows companies to manage computing power, storage, and networks — much like Amazon Web Services (AWS) or Microsoft Azure, only self-hosted and fully customizable.

The platform consists of several modules, so-called “services”:

• Nova - Management of virtual machines (compute)
• Neutron - network management
• Cinder - block storage
• Swift - object storage
• Keystone - authentication and identity management

Each of these modules can be operated independently or combined with each other via APIs.

What is an API — and what is its role in OpenStack?

API stands for Application Programming Interface. Put simply, an API is an interface that software applications use to communicate with each other.

In OpenStack, APIs are used to automatically control cloud resources. Instead of manually creating a virtual machine on the dashboard, developers can send commands to start servers, configure networks, or provide storage space.

example:
A DevOps team wants to automatically deploy 10 new test servers a day. With the OpenStack API, this can be done by script — quickly, reproducibly and without human intervention.

OpenStack API structure

OpenStack is modular — this also applies to its APIs.
Here are the most important interfaces:

The OpenStack APIs are REST-based, use HTTP methods (GET, POST, DELETE), and return data in JSON format — ideal for developers working with modern frameworks.

OpenStack API call example

A simple API call to get a list of all servers looks like this:

curl -X GET http://openstack.example.com:8774/v2.1/servers \
-H "X-Auth-Token: <your_token>"

This command uses the Nova API to query all servers that belong to a specific project. The result is a JSON response with all instances — including status, name, and resource usage.

Benefits of the OpenStack API

The API structure provides numerous benefits for companies and developers:

• Automation: Routine tasks can be automated using a script or tool.
• Integration: Compatible with DevOps tools such as Terraform, Jenkins, or Ansible.
• Scalability: Resources can be adjusted in seconds as needed.
• Cost efficiency: Companies retain full control over infrastructure and costs.
• Flexibility: Access to individual modules without changing the entire system.
  
  

Agencies or internal teams working on complex cloud architectures or app projects in particular benefit greatly from these opportunities.

Challenges and limits

Despite many benefits, working with OpenStack APIs also presents challenges:

• Technical expertise: APIs require programming experience and an understanding of authentication (e.g. tokens).
• Complexity: Different API versions (e.g. Nova v2 vs. v3) can cause compatibility issues.
• Documentation: Although OpenStack is open, the API documentation is extensive and sometimes difficult to penetrate.
  
  

An experienced agency for cloud or app development can provide support here to professionally implement architecture, security and scaling.

OpenStack API in practice

Companies use OpenStack APIs to establish automated workflows. examples:

• Start and stop virtual machines during development cycles
• Automatic scaling of resources during heavy usage
• Integration with monitoring tools for fault analysis
• Building continuous integration pipelines for software deployments

This creates an efficient, flexible cloud environment that is ideal for modern software and app projects.

conclusion

The OpenStack API is the backbone of modern open-source cloud infrastructures. It enables developers to automate processes, integrate systems, and control the cloud according to individual requirements.

For companies that rely on automation, security and scalability, OpenStack is a future-proof solution — especially in combination with experienced partners such as Komodo, who bridge the gap between technology, design and implementation.