What is Policy as Code? Definition and Benefits

With policy as code, policies can be managed and automated using code written in a high-level language. It is a programmatic method of uniformly defining and enforcing policies throughout cloud-native applications and their infrastructure. 

Automation in software development is the key to scaling and reducing costs in the cloud-native environment. This need for automation also explains the rise of the “everything-as-code” philosophy. Continuing to rely on manual processes for security and compliance can diminish the benefits of using code to automate other operations, such as the management of infrastructure and CI/CD pipelines.  

Policy as code can help you automate security and compliance procedures to reduce human error and the time-to-market pressure on developer teams. It effectively removes the need to check for compliance manually. A report by Egress found that human error was responsible for 84% of cybersecurity incidents in 2021. 

Policy as code provides an organizational standard for authorization across the entire cloud-native infrastructure. Policies are written and enforced using the same tools and policy language, leading to better reporting, understanding and implementation of system-wide and application-level policies.

At the same time, policies represented as code in text files also allow a broader range of stakeholders to understand them and lead to the implementation of software development best practices, such as testing and version control. 

Within the IT context, a policy is a set of rules, guidelines or instructions for using IT resources and running operations. A policy could be a set of conditions a code must fulfill to pass a security control and deploy. It could also be an authorization policy that defines the scope of access for an asset or resource.  

Legacy policy enforcement methods do not take advantage of decoupled policy as code and hardcode authorization rules into the application. As a result, these policies are neither versionable nor repeatable. In addition, these systems do not allow for policy testing, leading to an incompatibility with automated testing procedures. 

Policy as code is a method to uniformly write, maintain and implement these policies across the development lifecycle using code. 

Usually, a policy engine, such as the Open Policy Agent (OPA), is used to enforce these policies. Policies in OPA are written using Rego, a declarative policy language. Policy as code can also be written in other programming languages, such as Python and YAML, depending on your management and enforcement tools. 

Policy as code commonly requires three inputs: data, query and the policy code. The policy as code tool — OPA, in this case — evaluates the query input against the data and policy code before reaching a decision and returning the query result in JSON format. 

OPA provides developers with a unified policy language, policy engine and tooling to implement policy as code across the entire cloud-native stack. Learning the Rego policy language may take some time, but it’s well worth the effort.

Enroll in a free course at Styra Academy and get started today. 

When compared to alternative methods of policy enforcement, policy as code solutions offer the following benefits: 

1. Automation

Policies written as source code allow for automated sharing and enforcement of policies at an unlimited scale. Automation also increases overall efficiency by reducing human errors and helping teams speed up the development process.

2. Shift security and compliance left

Doing security and compliance testing in post-production usually returns a large volume of bugs that leaves developers overwhelmed. As a result, they often end up focusing only on the most critical ones. 

Shifting left means testing the application early in the software delivery process. Using security policy as code puts guardrails around the build and deployment phases, ensuring any issues or misconfigurations can be found and fixed early on. 

Policy as code also enables you to monitor and audit policy enforcement across all access points in real-time, making it easy to catch violations and meet compliance requirements. 

3. Centralized policy management

A policy as code tool often comes with a control plane where you can manage and update policies for all services and applications in your technology stack. Styra Declarative Authorization Service (DAS) is the only enterprise-grade control plane designed explicitly for OPA that includes authoring, testing, distribution and monitoring of policy. It makes sense that the people who created OPA (hint: Styra) would know a thing or two about managing it. 

4. Version control

You can add text files containing code to a version control system and reap the benefits of these systems, such as revision history, peer review and collaboration.. If a new policy creates a problem, you can easily revert to a previous version.

5. Visibility

Policy as code allows all stakeholders to understand the system rules and regulations. Policies can be reviewed by looking at the code instead of asking another engineer and waiting for a response. 

Policy as code is not to be confused with policy in code. Writing policies within the software code is nothing new to developers but this coupling has several drawbacks. These embedded policies can not be reused or shared across different teams and applications. Making any changes or errors in the policy code could affect other business functions or entirely crash the application. 

Another con of policy in code is that it is prone to inaccuracies, leading to negative consequences such as the failure to meet compliance and regulatory laws. Companies lose an average of $4 million in revenue after a non-compliance event, according to a study by GlobalScape.

Writing policy as a code separately from the business logic means each component of an application has its own discrete, decoupled policy enforcement agent. This policy decoupling allows for quick and easy policy changes with no impact on the other functions of the application. The policy code also becomes a reusable block, which is especially helpful in a microservice application with many services and multiple access points that require authorization. 

Only decoupling policy from the underlying code could not have solved authorization issues for microservices. Development teams often use different programming languages when designing services for the same application and it would be almost impossible to know how to query them all when running reports. Policy as code also needed a standard and a unified policy language. Here’s where OPA and Rego come in.

With the support of an active open-source community and widespread adoption, OPA has become the de facto standard for policy as code in the cloud-native environment. A unified policy language solves the problems of polyglot architectures, allowing any authorized person to manage policies easily. 

To further reduce the burden of designing and implementing authorization on developers, Styra DAS comes with built-in policy libraries that meet compliance and regulatory requirements and allows you to test the impact of policies before implementing them. 

Take advantage of policy as code and get your authorization needs sorted out within minutes. Request a custom demo from our team today!

To make sure all processes adhere to the same software development best practices, everything-as-code treats operations, infrastructure management, policies, security and compliance as application code. 

IT operations and security teams have practiced infrastructure as code for years. It involves configuring infrastructure using machine-readable files instead of hardware and manual processes. Policy as code follows the same principles to benefit security, compliance, data management and other functions.