Kapitan Overview

Kapitan at a glance

Kapitan is a powerful configuration management tool designed to help engineers manage complex systems through code. It centralizes and simplifies the management of configurations with a structured approach that revolves around a few core concepts.

Kapitan diagram

%%{ init: { securityLevel: 'loose'} }%%
graph LR
    classDef pink fill:#f9f,stroke:#333,stroke-width:4px,color:#000,font-weight: bold;
    classDef blue fill:#00FFFF,stroke:#333,stroke-width:4px,color:#000,font-weight: bold;
    TARGET1 --> KAPITAN
    TARGET2 --> KAPITAN
    TARGETN --> KAPITAN
    KAPITAN --> EXTERNAL
    KAPITAN --> GENERATORS
    KAPITAN --> HELM
    KAPITAN --> JINJA
    KAPITAN --> JSONNET
    KAPITAN --> KADET
    EXTERNAL --> OUTPUT
    GENERATORS --> OUTPUT
    JINJA --> OUTPUT
    JSONNET --> OUTPUT
    KADET --> OUTPUT
    HELM --> OUTPUT
    GKMS --> REFERENCES
    AWSKMS --> REFERENCES
    VAULT --> REFERENCES
    OTHER --> REFERENCES
    PLAIN --> REFERENCES
    OUTPUT --> TARGETN_OUTPUT
    OUTPUT --> TARGET1_OUTPUT 
    OUTPUT --> TARGET2_OUTPUT 
    REFERENCES --> KAPITAN
    TARGET1_OUTPUT --> DOCUMENTATION 
    TARGET1_OUTPUT --> KUBERNETES
    TARGET1_OUTPUT --> SCRIPTS 
    TARGET1_OUTPUT --> TERRAFORM
    CLASSES --> TARGET1
    CLASSES --> TARGET2
    CLASSES --> TARGETN

    subgraph "Inventory"
        CLASSES[classes]
        TARGET1(["target 1"]):::pink
        TARGET2(["target 2"])
        TARGETN(["target N"])
    end

    subgraph "references"
        direction TB
        GKMS["GCP KMS"]
        AWSKMS["AWS KMS"]
        VAULT["Hashicorp Vault"]
        OTHER["others"]
        PLAIN["plain"]
        REFERENCES["references"]
    end

    KAPITAN(("<img src='/images/kapitan_logo.png'; width='80'/>")):::blue
    click EXTERNAL "/compile#external"

    subgraph "Input Types" 
        EXTERNAL["external"]
        GENERATORS["generators"]
        HELM["helm"]
        JINJA["jinja"]
        JSONNET["jsonnet"]
        KADET["kadet"]
    end

    OUTPUT{{"compiled output"}}:::blue



    subgraph " "
        TARGET1_OUTPUT([target1]):::pink
        DOCUMENTATION["docs"]
        KUBERNETES["manifests"]
        SCRIPTS["scripts"]
        TERRAFORM["terraform"]
    end

    TARGET2_OUTPUT(["target 2"])
    TARGETN_OUTPUT(["target N"])

Let's explore these concepts in a way that's accessible to new users:

Inventory

At the core of Kapitan lies the Inventory, a structured database of variables meticulously organized in YAML files. This hierarchical setup serves as the single source of truth (SSOT) for your system's configurations, making it easier to manage and reference the essential components of your infrastructure. Whether you're dealing with Kubernetes configurations, Terraform resources, or even business logic, the Inventory allows you to define and store these elements efficiently. This central repository then feeds into Kapitan's templating engines, enabling seamless reuse across various applications and services.

Input Types

Kapitan takes the information stored in the Inventory and brings it to life through its templating engines upon compilation. This process transforms static data into dynamic configurations, capable of generating a wide array of outputs like Kubernetes manifests, Terraform plans, documentation, and scripts. It's about making your configurations work for you, tailored to the specific needs of your projects.

See Input Types for more

Generators

Generators offer a straightforward entry point into using Kapitan, requiring minimal to no coding experience. These are essentially pre-made templates that allow you to generate common configuration files, such as Kubernetes manifests, directly from your Inventory data. Kapitan provides a wealth of resources, including the Kapitan Reference GitHub repository and various blog posts, to help users get up and running with generators.

Kadet

For those looking to leverage the full power of Kapitan, Kadet introduces a method to define and reuse complex configurations through Python. This internal library facilitates the creation of JSON and YAML manifests programmatically, offering a higher degree of customization and reuse. Kadet empowers users to craft intricate configurations with the simplicity and flexibility of Python.

References

Kapitan References provide a secure way to store passwords, settings, and other essential data within your project. Think of them as special code placeholders.

• Flexibility: Update a password once, and Kapitan updates it everywhere automatically.
• Organization: References tidy up your project, especially when you're juggling multiple settings or environments (dev, staging, production). Security: Protect sensitive information like passwords with encryption

Tip

Use Tesoro, our Kubernetes Admission Controller, to complete your integration with Kubernetes for secure secret decryption on-the-fly.