[SOLVED] Pass environment variable into a Vue App at runtime - kubernetes

[SOLVED] How to Pass Environment Variables into a Vue App at Runtime in Kubernetes

In this article, we will look at simple ways to pass environment variables into a Vue app when it runs on Kubernetes. It is important to handle environment variables the right way. This is especially true in changing environments like Kubernetes. We will share different methods to help you manage and add environment variables to your Vue app. This will help your app run well and be flexible.

Here is a quick list of the methods we will talk about:

Solution 1 - Use ConfigMaps to Manage Environment Variables
Solution 2 - Inject Environment Variables at Build Time with Vue CLI
Solution 3 - Accessing Environment Variables in Vue Components
Solution 4 - Using Kubernetes Downward API to Expose Pod Metadata
Solution 5 - Modifying the Vue App Configuration to Read Environment Variables
Solution 6 - Implementing a Runtime Configuration File

By knowing these methods, we will be ready to manage environment variables in our Vue apps on Kubernetes. If you want to learn more, you can look at our articles on how to pull environment variables and exposing services in Kubernetes. These articles give more details about Kubernetes setups.

Solution 1 - Use ConfigMaps to Manage Environment Variables

We can use ConfigMaps in Kubernetes to manage environment variables for our Vue application while it runs. ConfigMaps let us keep environment-specific settings separate from our application code. This way, we can change these settings without having to rebuild the app.

Step 1: Create a ConfigMap

First, we create a ConfigMap that holds our environment variables. We can do this using a YAML file or by using the kubectl command line.

Example YAML for ConfigMap:

apiVersion: v1
kind: ConfigMap
metadata:
  name: vue-app-config
data:
  VUE_APP_API_URL: "https://api.example.com"
  VUE_APP_OTHER_CONFIG: "some_value"

Now we apply the ConfigMap to our Kubernetes cluster:

kubectl apply -f configmap.yaml

Step 2: Mount the ConfigMap as Environment Variables

Next, we need to link this ConfigMap in our deployment YAML file. This will let us add the environment variables into our Vue application’s container.

Example Deployment YAML:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: vue-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: vue-app
  template:
    metadata:
      labels:
        app: vue-app
    spec:
      containers:
        - name: vue-app
          image: your-vue-app-image:latest
          env:
            - name: VUE_APP_API_URL
              valueFrom:
                configMapKeyRef:
                  name: vue-app-config
                  key: VUE_APP_API_URL
            - name: VUE_APP_OTHER_CONFIG
              valueFrom:
                configMapKeyRef:
                  name: vue-app-config
                  key: VUE_APP_OTHER_CONFIG
          ports:
            - containerPort: 8080

Step 3: Access Environment Variables in Vue App

Now that we injected the environment variables, we can use them in our Vue application with process.env:

console.log(process.env.VUE_APP_API_URL); // Outputs: https://api.example.com

Benefits of Using ConfigMaps

Dynamic Configuration: We can change the values in the ConfigMap without changing the application code or redeploying the container.
Separation of Concerns: It helps us keep a clear line between configuration and code. This makes our app more flexible and easier to manage.
Centralized Management: ConfigMaps allow for central management of our environment variables. This is very helpful in different environment cases.

For more info on managing configuration in Kubernetes, we can check this guide on using ConfigMaps.

By using ConfigMaps, we can manage environment variables in our Vue application that runs in a Kubernetes environment.

Solution 2 - Inject Environment Variables at Build Time with Vue CLI

To add environment variables into a Vue app at build time, we can use Vue CLI’s built-in features. This way is good for setting up values that our Vue app needs when it runs. It also makes it easier to manage settings for different environments.

Step 1: Define Environment Variables

We can create environment variable files in our Vue project folder. The Vue CLI understands these files:

.env for default values
.env.local for local development changes
.env.[mode] for specific modes like .env.production or .env.development

Each of these files can have key-value pairs like this:

VUE_APP_API_URL=https://api.example.com
VUE_APP_OTHER_VARIABLE=some_value

Remember that all keys for environment variables need to start with VUE_APP_. This is needed for the Vue CLI to include these variables in the build.

Step 2: Access Environment Variables in Your Vue App

After we define the environment variables, we can use them in our Vue components or JavaScript files. We do this with process.env. For example, to use the VUE_APP_API_URL variable, we can write:

export default {
  data() {
    return {
      apiUrl: process.env.VUE_APP_API_URL,
    };
  },
  created() {
    console.log("API URL: ", this.apiUrl);
  },
};

Step 3: Build Your Vue App

When we build our Vue app using CLI commands, the environment variables we defined will go into the application code. We can build our app by running:

npm run build

Step 4: Deploying with Kubernetes

After we build our app, we can deploy it to our Kubernetes cluster. Make sure that our Docker image is built with the right environment variables. We can check the Kubernetes documentation for more details on how to deploy Docker images.

By doing these steps, we can easily inject environment variables at build time in our Vue app. This method helps us manage configurations easily. It also works well in different environments. This way, our Vue app will run smoothly in production, development, or testing.

Solution 3 - Accessing Environment Variables in Vue Components

We can access environment variables in our Vue components using the process.env object. This object is part of our Vue application. It helps us read the environment variables that we set up in the build or add at runtime.

Setting Up Environment Variables

Define Environment Variables: We can set up environment variables in the .env files at the root of our Vue project. For example:

.env
```
VUE_APP_API_URL=https://api.example.com
VUE_APP_FEATURE_FLAG=true
```
Remember that all variable names need to start with VUE_APP_ to work in the Vue application.

Accessing Variables in Vue Components: To use these environment variables in our Vue components, we just use process.env like this:

<template>
  <div>
    <h1>Welcome to My Vue App</h1>
    <p>API URL: {{ apiUrl }}</p>
    <p>Feature Flag: {{ featureFlag }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      apiUrl: process.env.VUE_APP_API_URL,
      featureFlag: process.env.VUE_APP_FEATURE_FLAG === 'true'
    }
  }
}
</script>

Accessing Environment Variables at Runtime

If we want to show environment variables at runtime, especially when we deploy our Vue app on Kubernetes, we can create a runtime-config.js file. This file will read the environment variables and make them available for our app.

Create a Runtime Configuration File: We need to create a file called runtime-config.js in our public directory:

public/runtime-config.js

window.env = {
  API_URL: process.env.VUE_APP_API_URL || "default_api_url",
  FEATURE_FLAG: process.env.VUE_APP_FEATURE_FLAG || "false",
};

Include the Configuration in Your HTML: We include this script in our index.html file:

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width,initial-scale=1.0" />
    <title>Vue App</title>
    <script src="/runtime-config.js"></script>
  </head>
  <body>
    <noscript>
      <strong
        >We are sorry but Vue App doesn't work well without JavaScript.
        Please enable it to continue.</strong
      >
    </noscript>
    <div id="app"></div>
    <script src="/js/app.js"></script>
  </body>
</html>

Accessing Runtime Variables in Components: Now we can get these variables in our Vue components using window.env:

<script>
export default {
  data() {
    return {
      apiUrl: window.env.API_URL,
      featureFlag: window.env.FEATURE_FLAG === 'true'
    }
  }
}
</script>

Deployment Considerations

When we deploy our Vue app on Kubernetes, we need to make sure our environment variables are set correctly in the container specifications. We can use ConfigMaps or Secrets to manage these variables well.

For more info on managing environment variables in Kubernetes, check the ConfigMaps documentation. This way, we can add environment variables at runtime and make sure our application has the right setup based on the deployment context.

Solution 4 - Using Kubernetes Downward API to Expose Pod Metadata

We can use the Kubernetes Downward API to easily pass environment variables into a Vue app while it runs. This way, we can show metadata about the pod. This includes the pod name, namespace, labels, and annotations. The Downward API helps us set environment variables in our Kubernetes deployment YAML file.

Step-by-Step Guide

Define Environment Variables in Deployment: We need to change our Kubernetes deployment YAML to add environment variables that link to the pod metadata. For example:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-vue-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: my-vue-app
  template:
    metadata:
      labels:
        app: my-vue-app
    spec:
      containers:
        - name: my-vue-container
          image: my-vue-image:latest
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
            - name: POD_LABELS
              valueFrom:
                fieldRef:
                  fieldPath: metadata.labels

In this example, we create three environment variables: POD_NAME, POD_NAMESPACE, and POD_LABELS. These variables will get filled with the pod’s metadata values.

Access Environment Variables in Vue App: In our Vue app, we can get these environment variables with process.env. For example, we can log the pod metadata in our main Vue component:

export default {
  mounted() {
    console.log("Pod Name:", process.env.POD_NAME);
    console.log("Pod Namespace:", process.env.POD_NAMESPACE);
    console.log("Pod Labels:", process.env.POD_LABELS);
  },
};

Build and Deploy: After we change our deployment settings, we need to apply the updates:
```
kubectl apply -f your-deployment.yaml
```
After we deploy it, our Vue app will have access to the pod’s metadata using the environment variables we defined.

Advantages

Dynamic Values: Environment variables fill at runtime. This helps our app to adjust to different environments or settings without needing to change the code.
Easy Access: The Downward API gives us a simple way to get important metadata about the pod. This makes it easier to manage settings.

This method is great for apps that need to act differently based on where they are deployed. It helps make our Vue app more flexible in a Kubernetes environment.

For more about managing settings and values in Kubernetes, we can check how to set dynamic values or look into ways to share storage between pods.

Solution 5 - Changing the Vue App Settings to Read Environment Variables

We can pass environment variables into our Vue app when it runs. To do this, we need to change the Vue app settings so it reads these variables. This way, we can access environment variables directly in our Vue components. This is great for settings that need to change based on where we deploy.

Step 1: Create a `.env` File

First, we create a .env file in the main folder of our Vue project. This file will store our environment variables. For example:

VUE_APP_API_URL=https://api.example.com
VUE_APP_OTHER_VARIABLE=value

Step 2: Change `vue.config.js`

Next, we need to change our vue.config.js file. This will help our Vue app read the environment variables. We can add this configuration:

// vue.config.js
const { defineConfig } = require("@vue/cli-service");

module.exports = defineConfig({
  transpileDependencies: true,
  configureWebpack: {
    plugins: [
      new webpack.DefinePlugin({
        "process.env": {
          VUE_APP_API_URL: JSON.stringify(process.env.VUE_APP_API_URL),
          VUE_APP_OTHER_VARIABLE: JSON.stringify(
            process.env.VUE_APP_OTHER_VARIABLE,
          ),
        },
      }),
    ],
  },
});

This setup clearly defines the environment variables. Now they are available in our Vue app.

Step 3: Access Environment Variables in Vue Components

In our Vue components, we can use process.env to access these environment variables. For example:

<template>
  <div>
    <h1>API URL: {{ apiUrl }}</h1>
  </div>
</template>

<script>
export default {
  data() {
    return {
      apiUrl: process.env.VUE_APP_API_URL
    };
  }
};
</script>

Step 4: Build and Deploy the Application

When we build and deploy our Vue app, we must make sure the environment variables in our Kubernetes deployment settings are set correctly. For example, we can use a ConfigMap to set these variables.

Step 5: Using ConfigMap in Kubernetes

To make sure the environment variables go to the container, we create a ConfigMap in Kubernetes:

apiVersion: v1
kind: ConfigMap
metadata:
  name: vue-app-config
data:
  VUE_APP_API_URL: "https://api.example.com"
  VUE_APP_OTHER_VARIABLE: "value"

Then we need to link this ConfigMap in our Pod or Deployment settings:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: vue-app
spec:
  replicas: 1
  template:
    spec:
      containers:
        - name: vue-app
          image: your-vue-app-image
          env:
            - name: VUE_APP_API_URL
              valueFrom:
                configMapKeyRef:
                  name: vue-app-config
                  key: VUE_APP_API_URL
            - name: VUE_APP_OTHER_VARIABLE
              valueFrom:
                configMapKeyRef:
                  name: vue-app-config
                  key: VUE_APP_OTHER_VARIABLE

Conclusion

By changing the Vue app settings to read environment variables, we help our app respond to different environments without putting hardcoded values. This way is very helpful when we deploy the app in different places with Kubernetes. It lets us manage settings using ConfigMaps easily. For more details on how to manage settings in Kubernetes, check this article on how to set dynamic values with Helm.

Solution 6 - Implementing a Runtime Configuration File

To pass environment variables into a Vue app at runtime, we can use a runtime configuration file. This method lets us set up our Vue application based on the environment variables we define in our Kubernetes deployment. Here is how to do it:

Create a Configuration File: First, we need to create a configuration file to hold our environment variables. This file will be served by our web server. Then, our Vue app can access it at runtime. We can name this file config.js.
```
// config.js
window.env = {
  API_URL: "https://api.example.com",
  OTHER_VARIABLE: "value",
};
```
Serve the Configuration File: We must make sure this config.js file is easy to access from our Vue app. We can place it in the public directory of our Vue project. This way, it can be served directly.
Modify Your Kubernetes Deployment: We should update our Kubernetes deployment configuration to include the environment variables in the config.js file. We can use a ConfigMap to manage our environment variables easily.
```
apiVersion: v1
kind: ConfigMap
metadata:
  name: vue-config
data:
  config.js: |
    window.env = {
        API_URL: "${API_URL}",
        OTHER_VARIABLE: "${OTHER_VARIABLE}"
    };
```
In this example, ${API_URL} and ${OTHER_VARIABLE} will change to the actual values from our Kubernetes environment.

Mount the ConfigMap: In our deployment, we need to mount the ConfigMap as a volume. This step makes sure the config.js file is available to our application.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: vue-app
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: vue-app
    spec:
      containers:
        - name: vue-container
          image: your-vue-image
          volumeMounts:
            - name: config-volume
              mountPath: /usr/share/nginx/html/config.js
              subPath: config.js
      volumes:
        - name: config-volume
          configMap:
            name: vue-config

Access the Configuration in Vue: After we have the configuration file, we can access the environment variables in our Vue components. We use the global window.env object.
```
// In your Vue component
export default {
  created() {
    console.log("API URL:", window.env.API_URL);
  },
};
```
Build and Deploy: Finally, we need to build our Vue application and deploy it to our Kubernetes cluster. We must check that our environment variables are set correctly in our Kubernetes deployment. This way, we will see the changes in our application at runtime.

This way of using a runtime configuration file is very useful. It helps us pass environment variables into a Vue app in Kubernetes. It gives us flexibility and makes management easier. For more information on Kubernetes ConfigMaps, we can check this guide on managing environment variables. In conclusion, we see that passing environment variables into a Vue app at runtime in a Kubernetes environment is very important for changing settings. We looked at different ways to do this. We talked about using ConfigMaps. We also discussed injecting variables when we build the app. Another method is using the Downward API. This helps us manage app settings better.

If we want more information on how to set dynamic values and work with Kubernetes settings, we can look at our guides on how to set dynamic values and Kubernetes best practices.

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[SOLVED] Pass environment variable into a Vue App at runtime - kubernetes

[SOLVED] How to Pass Environment Variables into a Vue App at Runtime in Kubernetes

Solution 1 - Use ConfigMaps to Manage Environment Variables

Step 1: Create a ConfigMap

Step 2: Mount the ConfigMap as Environment Variables

Step 3: Access Environment Variables in Vue App

Benefits of Using ConfigMaps

Solution 2 - Inject Environment Variables at Build Time with Vue CLI

Step 1: Define Environment Variables

Step 2: Access Environment Variables in Your Vue App

Step 3: Build Your Vue App

Step 4: Deploying with Kubernetes

Solution 3 - Accessing Environment Variables in Vue Components

Setting Up Environment Variables

Accessing Environment Variables at Runtime

Deployment Considerations

Solution 4 - Using Kubernetes Downward API to Expose Pod Metadata

Step-by-Step Guide

Advantages

Solution 5 - Changing the Vue App Settings to Read Environment Variables

Step 1: Create a `.env` File

Step 2: Change `vue.config.js`

Step 3: Access Environment Variables in Vue Components

Step 4: Build and Deploy the Application

Step 5: Using ConfigMap in Kubernetes

Conclusion

Solution 6 - Implementing a Runtime Configuration File

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Best Online Tutorials

[SOLVED] Pass environment variable into a Vue App at runtime - kubernetes

[SOLVED] How to Pass Environment Variables into a Vue App at Runtime in Kubernetes

Solution 1 - Use ConfigMaps to Manage Environment Variables

Step 1: Create a ConfigMap

Step 2: Mount the ConfigMap as Environment Variables

Step 3: Access Environment Variables in Vue App

Benefits of Using ConfigMaps

Solution 2 - Inject Environment Variables at Build Time with Vue CLI

Step 1: Define Environment Variables

Step 2: Access Environment Variables in Your Vue App

Step 3: Build Your Vue App

Step 4: Deploying with Kubernetes

Solution 3 - Accessing Environment Variables in Vue Components

Setting Up Environment Variables

Accessing Environment Variables at Runtime

Deployment Considerations

Solution 4 - Using Kubernetes Downward API to Expose Pod Metadata

Step-by-Step Guide

Advantages

Solution 5 - Changing the Vue App Settings to Read Environment Variables

Step 1: Create a .env File

Step 2: Change vue.config.js

Step 3: Access Environment Variables in Vue Components

Step 4: Build and Deploy the Application

Step 5: Using ConfigMap in Kubernetes

Conclusion

Solution 6 - Implementing a Runtime Configuration File

Labels

Comments

Post a Comment

Step 1: Create a `.env` File

Step 2: Change `vue.config.js`