Managing environment-specific configurations, such as database URLs, API keys, and log levels, is crucial for deploying applications using Helm charts. In this blog post, we'll explore various approaches to simplify the injection of environment variables into Helm chart deployments. We'll cover techniques like using .env files, Helmfile, Kustomize, Helm Secrets, and custom chart helper scripts.

Conquer the chaos of multi-environments

When we embark on the journey of deploying a Helm chart in different environments, we are often confronted with the daunting challenge of managing an array of variables specific to each environment. From database connection URLs to API keys and logging levels, the multitude of configurations can quickly become overwhelming. It's like a puzzle with countless pieces scattered across different landscapes, requiring a clever solution to bring them all together seamlessly. But fear not! This blog post will unravel the secrets of simplifying environment variable injection in Helm chart deployments. Get ready to unlock the secret sauce and conquer the chaos!

Understanding the Importance of Environment Variable Injection

In the vast realm of application deployment, the importance of environment-specific configurations cannot be overstated. Every environment—be it development, staging, or production—comes with its unique set of requirements and settings. These can include database connections, API keys, credentials, endpoints, and logging configurations, among others. Ensuring that these variables are correctly injected into the deployed Helm charts is paramount for achieving consistent behavior and maintaining the desired functionality across different environments.

Managing multiple environments with their associated configurations can quickly become a challenging endeavor. Manually updating values for each environment introduces room for human error and increases the risk of inconsistency between deployments. Furthermore, maintaining separate sets of values for each environment requires meticulous attention to detail, making the entire process time-consuming and prone to errors.

Enter environment variable injection—a dynamic and flexible approach to managing these configurations. By utilizing environment variables, we gain the ability to decouple configuration values from the Helm charts themselves, making deployments more adaptable and streamlined. Environment variables allow for centralization and provide a standardized method to control application behavior across different environments.

With environment variable injection, we can easily modify and update configurations based on specific requirements, all without touching the Helm charts directly. This approach empowers DevOps teams to swiftly adapt to changing environments, seamlessly switch between different deployment stages, and effortlessly accommodate varying infrastructure setups. By abstracting the configurations into environment variables, we achieve a modular and scalable deployment approach that can be efficiently managed, modified, and shared.

Examples

.env.production

DATABASE_URL=production_db_url
API_KEY=production_api_key
LOG_LEVEL=info

.env.stage

DATABASE_URL=staging_db_url
API_KEY=staging_api_key
LOG_LEVEL=debug

values.yaml:

database:
  url: REPLACE_WITH_DATABASE_URL
api:
  key: REPLACE_WITH_API_KEY
logging:
  level: REPLACE_WITH_LOG_LEVEL

In this example, the .env.production and .env.stage files contain environment-specific configurations for the database URL, API key, and log level. The values.yaml file uses placeholder values (REPLACE_WITH_...) for these variables.

In the following sections, we will explore several techniques and tools that facilitate environment variable injection for Helm chart deployments. From utilizing .env files to automating with Helmfile and leveraging the power of Kustomize and Helm Secrets, we will delve into the world of possibilities, providing you with the knowledge and tools to simplify your deployment workflows. Let's dive in and unlock the potential of environment variable injection in Helm charts!

Leveraging .env Files for Helm Chart Deployments

When it comes to managing environment-specific variables in Helm chart deployments, .env files emerge as a powerful tool in our arsenal. .env files, short for environment files, provide a structured and convenient approach to storing and organizing configuration values for different environments. They act as a central repository for variables that are specific to each deployment stage, eliminating the need to scatter these values across multiple files or configurations.

By separating the configuration values from the Helm charts themselves, .env files enable a higher level of flexibility and modularity. This decoupling allows us to tailor the deployment to a particular environment without making modifications directly to the chart or its values.yaml file. Instead, we can update the .env file associated with the environment, making it easier to manage and maintain the configurations across different stages of the deployment pipeline.

Using .env files in Helm chart deployments offer numerous benefits. Firstly, it simplifies the process of managing environment-specific variables. With a well-structured .env file, we can easily locate and update the necessary values, ensuring consistency and accuracy throughout the deployment process. Additionally, .env files provide an intuitive format, usually in a key-value pair structure, which allows for easy comprehension and readability.

Another advantage of utilizing .env files is the ability to leverage existing tools and libraries that support environment file parsing. These tools can automatically load the variables from the .env file and make them available for consumption by the Helm deployment process. This streamlined workflow minimizes manual intervention, reduces the risk of errors, and boosts productivity.

To incorporate .env files into your Helm chart deployment workflow, you can utilize various methods such as custom scripts or third-party plugins like Helm Secrets or Helmfile. These tools seamlessly integrate with Helm, allowing for the straightforward and efficient injection of environment variables into the deployment process.

By embracing the power of .env files, Helm chart deployments become more agile and adaptable. They offer a scalable approach to managing environment-specific configurations, paving the way for smoother transitions between development, staging, and production environments. With .env files in your toolkit, you gain control over your deployment variables, ensuring that each environment has the precise configurations it requires, without the hassle of manual updates or complex configuration management.

Please, please, please note that while this approach can inject environment variables into Helm charts, it's crucial to handle sensitive information securely, such as ensuring appropriate access permissions for the .env files and considering using a secret management solution for sensitive data like API keys or database credentials.

In the next section, we will explore how Helmfile can be combined with .env files to further simplify and automate the deployment process, enabling you to orchestrate your Helm deployments with ease. Get ready for an exciting journey into the world of Helmfile and environment variables!

Simplifying Deployment with helmfile and .env Files

helmfile, a powerful declarative tool for managing Helm chart deployments, provides a streamlined approach to orchestrate and manage multiple Helm releases. When combined with .env files, Helmfile becomes even more potent, simplifying the deployment process and enhancing the management of environment-specific configurations.

By leveraging Helmfile's capabilities alongside .env files, you can define your Helm releases in a single declarative YAML file, while the environment-specific configurations reside in separate .env files. This separation of concerns allows for efficient management of environment variables without cluttering the Helmfile itself.

To get started, you define your Helm releases in the Helmfile YAML, specifying the chart name, release name, chart version, and other parameters. Instead of hardcoding the environment-specific values, you can reference the corresponding variables defined in the .env file for each environment. This approach decouples the release configurations from the specific environment, providing flexibility and modularity.

When it's time to deploy, Helmfile dynamically loads the variables from the associated .env file and injects them into the Helm chart deployments. This automation eliminates the need for manual intervention and ensures that the correct variables are applied to each environment consistently.

The use of helmfile and .env files in tandem offers several benefits. Firstly, it simplifies the management of multiple environments by centralizing the configurations in dedicated .env files. This organization reduces the risk of misconfiguration or confusion between environments and ensures that the appropriate values are utilized for each deployment stage.

Furthermore, Helmfile enables the definition of dependencies between releases, allowing for orchestrated deployments and easier management of complex application stacks. With the ability to define and control the deployment order, you can ensure that dependent services are deployed in the correct sequence, minimizing potential errors and ensuring a smooth deployment process.

Additionally, Helmfile integrates with popular source control systems, enabling version-controlled management of Helm releases and configurations. This integration facilitates collaboration, auditability, and reproducibility of deployments, enhancing the overall reliability of your application delivery pipeline.

Example combining helmfile with .env files

Combining helmfile with .env files, you achieve a powerful and efficient workflow for managing environment-specific configurations in Helm chart deployments. The ability to declaratively define releases and reference environment variables simplifies the management of configurations across different environments, eliminating the need for manual adjustments or modifications to Helm charts.

helmfile.yaml:

releases:
  - name: myapp-stage
    chart: myapp-chart
    values:
      - values.yaml
    envValues:
      - .env.common
      - .env.stage

In this example, the helmfile.yaml specifies the releases to deploy. The myapp-stage release uses the myapp-chart chart and includes values.yaml as the values file.

The envValues section allows you to inject values from multiple .env files. In this case, it includes .env.common and .env.stage. You can add more .env files if needed.

.env.common:

NAMESPACE=myapp-namespace

The .env.common file contains common environment variables used across all environments. In this example, it defines the NAMESPACE variable.

.env.stage:

DATABASE_URL=staging_db_url
API_KEY=staging_api_key
LOG_LEVEL=debug

The .env.stage file contains environment-specific variables for the staging environment, such as DATABASE_URL, API_KEY, and LOG_LEVEL.

values.yaml:

database:
  url: ${DATABASE_URL}
api:
  key: ${API_KEY}
logging:
  level: ${LOG_LEVEL}

The values.yaml file uses placeholders (e.g., ${DATABASE_URL}) to reference the variables from the .env files. Helmfile will replace these placeholders with the corresponding values from the loaded .env files during deployment.

Remember to replace the placeholders in values.yaml with the appropriate syntax based on your chart's structure.

Install helmfile and execute:

helmfile apply

Finally, when you run the command above, helmfile will read the helmfile.yaml file and perform the deployments specified in the file. It will handle loading the .env files and injecting the values into the Helm charts based on the envValues section.

Make sure you have helmfile and helm CLI is installed on your system before running the command. helmfile acts as a wrapper around helm, providing additional features for managing multiple Helm releases and environments.

Note that you should run this command in the directory where your helmfile.yaml file is located. Additionally, ensure that you have the necessary permissions and access to deploy the Helm charts in your target environment.

This example demonstrates how to use helmfile to inject values from .env files into your Helm charts, providing environment-specific configurations during deployment.

In the next section, we will explore the utilization of Kustomize alongside .env files to inject variables into Helm charts, providing another approach to streamline and customize deployments. Brace yourself for a deep dive into the realm of Kustomize and environment variables! 🧑🏽‍🚀

Injecting Variables using kustomize and .env Files

kustomize, a Kubernetes-native configuration management tool that offers a powerful approach to customize and manage Kubernetes resources. When combined with .env files, kustomize becomes a valuable tool for injecting environment-specific variables into Helm charts, enabling flexible and dynamic deployments.

Said that we still can use kustomize with helm on the two use case examples below, continue reading. 🤓

Source: Reddit/r/kubernetes

By utilizing kustomize alongside .env files, you can separate the environment-specific configurations from the Helm charts themselves, simplifying the customization process. This separation allows you to modify the configurations for each environment without directly modifying the Helm charts or their values.yaml files.

To leverage kustomize and .env files, you define a Kustomization file that describes the desired customizations to be applied to the base Helm chart. In the Kustomization file, you reference the .env file associated with the specific environment and define patches or transformations to inject the variables into the Helm chart.

kustomize provides a range of customization options, including adding, modifying, or removing environment variables within the Helm chart's deployment manifest. With this flexibility, you can seamlessly inject environment-specific configurations such as database URLs, API keys, or log levels into the Helm chart deployments.

During the deployment process, kustomize automatically loads the variables from the .env file and applies the defined customizations to the Helm chart. This dynamic injection of environment variables ensures that the correct values are used for each deployment, streamlining the customization process and enabling consistent behavior across different environments.

The combination of kustomize and .env files brings several advantages to the table. Firstly, it allows for fine-grained customization of Helm chart deployments without modifying the underlying charts directly. This separation of concerns enhances maintainability, making it easier to update or replace the Helm charts while preserving the environment-specific configurations.

Moreover, kustomize provides an extensible framework that can be combined with other customization tools or techniques. For example, you can integrate kustomize with Helm Secrets or other encryption tools to securely manage and inject sensitive information into the Helm charts.

Additionally, kustomize integrates seamlessly with helm and helmfile, allowing for a cohesive and integrated deployment workflow. By combining these tools, you can achieve a comprehensive and robust solution for managing environment-specific configurations in Helm chart deployments.

The example use cases for kustomize and helm

As explained above, kustomize is designed to apply changes on deployed artifacts, then, I provide 2 scenarios to achieve this environment scenarios with kustomize:

1. Assuming your application uses a config-map to configure the parameters, this is the more natural and transparent way to use the environment files.

2. Using a helper script to change the values.yaml depending on the environment.

1. kustomize with Config Map

configmap.yaml, to define the common environment variables. Here's an example structure:

apiVersion: v1
kind: ConfigMap
metadata:
  name: myapp-configmap
data:
  DATABASE_URL: <default_db_url>
  API_KEY: <default_api_key>
  LOG_LEVEL: <default_log_level>

Replace <default_db_url>, <default_api_key>, and <default_log_level> with the default values you want to use.

.env.common:

NAMESPACE=myapp-namespace

.env.stage:

DATABASE_URL=staging_db_url
API_KEY=staging_api_key
LOG_LEVEL=debug

.env.prod:

DATABASE_URL=production_db_url
API_KEY=production_api_key
LOG_LEVEL=info

Use Kustomize to generate environment-specific ConfigMaps: kustomization.yaml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - configmap.yaml
configMapGenerator:
  - name: myapp-configmap
    env: .env.common

kustomization.stage.yaml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - configmap.yaml
configMapGenerator:
  - name: myapp-configmap
    env: .env.stage

kustomization.prod.yaml

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - configmap.yaml
configMapGenerator:
  - name: myapp-configmap
    env: .env.production

For the staging environment, run the following command:

kustomize build . | kubectl apply -f -

For the production environment, run the following command:

kustomize build . -o production-configmap.yaml
kubectl apply -f production-configmap.yaml

Assuming the chart's deployment would use the config-map predefined, similar to the following:

deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deployment
  namespace: $(NAMESPACE)
spec:
  # ...
  template:
    spec:
      containers:
        - name: myapp-container
          # ...
          envFrom:    # Use configMapRef instead of env
            - configMapRef:
                name: myapp-configmap
          # ...

Deploy the Chart:

helm install myapp myapp-chart -f values.yaml

2. kustomize with a helper script

Now, if you need to adapt the values.yaml per environment, let's do it with following helper to generate the corresponding environment values.yaml.

#!/bin/bash

ENV_NAME=$1
ENV_FILE=".env.${ENV_NAME}"
VALUES_FILE="values.yaml"
OUTPUT_FILE="values_${ENV_NAME}.yaml"

# Load environment variables from .env file
if [ -f "$ENV_FILE" ]; then
  set -o allexport
  source "$ENV_FILE"
  set +o allexport
else
  echo "Environment file not found: $ENV_FILE"
  exit 1
fi

# Generate modified values.yaml file
cp "$VALUES_FILE" "$OUTPUT_FILE"

# Replace variables in the modified values file
while IFS='=' read -r key value; do
  if [[ $key ]]; then
    sed -i "s/{{$key}}/$value/g" "$OUTPUT_FILE"
  fi
done < <(env)

echo "Modified values file generated: $OUTPUT_FILE"

In this script, the environment name is passed as an argument to the script ($1). It then uses that name to construct the corresponding .env file name and the modified values.yaml file name.

Here's an example of how to use the updated script:

./chart_helper.sh stage

This command will load the environment variables from .env.stage and generate a modified values_stage.yaml file based on the provided environment name.

Please note that you need to ensure the existence of the corresponding .env file with the appropriate environment-specific values (e.g., .env.stage) for the script to work correctly.

After running the script, you can deploy the Helm chart using the modified values_stage.yaml file:

helm install myapp myapp-chart -f values_stage.yaml

Remember to replace myapp with your desired release name and myapp-chart with the name of your Helm chart.

In the final section of this blog post, we will summarize the key takeaways and provide a comprehensive overview of the techniques and tools discussed. Get ready to unlock the full potential of environment variable injection and secure configuration management in your Helm chart deployments!

Summary and Key Takeaways

In this blog post, we have explored various techniques and tools to simplify environment variable injection and secure configuration management in Helm chart deployments. Let's summarize the key takeaways and highlight the main points covered throughout the article:

1. Environment Variable Injection:

   • Environment variables provide a flexible and modular approach to managing environment-specific configurations in Helm chart deployments.

   • Decoupling environment configurations from the Helm charts allow for easy customization and adaptability across different deployment stages.

2. .env Files:

   • .env files serve as a central repository for environment-specific variables, simplifying the management of configurations.

   • Separating variables into .env files enables efficient updates and reduces the risk of errors or inconsistencies.

3. Helmfile:

   • helmfile allows for declarative management of Helm chart deployments and integrates well with .env files.

   • With helmfile, you can define Helm releases in a single YAML file and reference environment variables from .env files.

4. Kustomize:

   • kustomize, combined with .env files, enables dynamic customization of Helm chart deployments without modifying the charts directly.

   • Environment variables can be injected into Helm charts using patches and transformations defined in the customization file.

By incorporating these techniques and tools into your Helm chart deployments, you can streamline your workflows, improve maintainability, and enhance the security of your configurations.

Remember the importance of maintaining a clear separation of concerns, and utilizing automation tools to simplify the process. Whether you choose to leverage .env files, helmfile, or kustomize, each approach offers unique advantages and empowers you to achieve efficient and reliable deployments.

With these insights and tools at your disposal, you are now equipped to master environment variable injection to improve your configuration management in your Helm chart deployments. Embrace the power of automation, simplify your workflows, and unlock the full potential of Helm!

Conclusion

There may be an open question, am I not exposing my sensitive data using these environment files?

In another post, I will share how to encrypt this information and we will explore the realm of Helm Secrets and encrypted secrets, providing a security-enhanced approach to managing sensitive information in your .env files for the Helm deployments. Wait for it and get ready to unlock the secrets of secure configuration management!

Deploying Helm charts with environment-specific configurations is made more accessible. We explored the approaches to streamline the process of injecting environment variables and improve the management of deployments in different environments.

Remember to consider security measures when handling sensitive information, and choose the method that aligns best with your project's requirements. With the right approach, you can enhance the efficiency and maintainability of your Helm deployments while ensuring the integrity of your application's configurations.

Thank you for joining us on this journey, and may your Helm chart deployments be seamless, adaptable, and secure!

If you found this post valuable, don't forget to share the love with colleagues, friends, and your community; subscribe to our newsletter, and visit our YouTube Channel.