"}]},{"@type":"HowToStep","name":"Test in Development and Production","text":"Run the Vite development server and build the project to ensure that the environment variables are correctly accessed in both environments. Check the console for any errors.","itemListElement":[{"@type":"HowToDirection","text":"npm run dev && npm run build"}]},{"@type":"HowToStep","name":"Verify Environment Variable Injection","text":"Inspect the built HTML file to confirm that the expected HTML tags are conditionally rendered based on the environment variable values.","itemListElement":[{"@type":"HowToDirection","text":"Open the built index.html and check for the presence of the expected elements."}]}]}
FG
๐Ÿ’ป Software๐ŸŒ Web & Full-Stack

Accessing env variables from index.html

Fresh3 days ago
Mar 14, 20260 views
Confidence Score70%
70%

Problem

Describe the bug I try to insert html tag by environment variable condition and use `vite-plugin-html` for it. But Vite behaviour is weird Reproduction https://github.com/xSorc/test-vite-index-env 1. This code works only in build [code block] During server i have this error [code block] 2. This code works only in dev server [code block] But during build this doesn't work, because Vite replace `process.env` with this: [code block] 3. The only option that works in both server and build is this: [code block] I suppose that first or second variant should works System Info Output of `npx envinfo --system --npmPackages vite,@vitejs/plugin-vue --binaries --browsers`: [code block] Used package manager: --- Before submitting the issue, please make sure you do the following - [x] Read the Contributing Guidelines. - [x] Read the docs. - [x] Check that there isn't already an issue that reports the same bug to avoid creating a duplicate. - [x] Provide a description in this issue that describes the bug. - [x] Make sure this is a Vite issue and not a framework-specific issue. For example, if it's a Vue SFC related bug, it should likely be reported to https://github.com/vuejs/vue-next instead. - [x] Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.

Error Output

error: Cannot use 'import.meta' outside a module while compiling ejs

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1 Fix

Canonical Fix
Unverified Fix
New Fix โ€“ Awaiting Verification

Fix Environment Variable Access in Vite for index.html

Medium Risk

The issue arises because Vite replaces `process.env` with static values during the build process, and `import.meta` cannot be used in non-module contexts like `index.html`. This leads to discrepancies between development and production environments when trying to access environment variables directly in HTML files.

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  1. 1

    Define Environment Variables in Vite Config

    Modify the Vite configuration to expose the necessary environment variables to the client-side code. Use the `define` option in `vite.config.js` to create global constants.

    javascript
    export default defineConfig({
      define: {
        'process.env.VARIABLE_NAME': JSON.stringify(process.env.VARIABLE_NAME)
      }
    });
  2. 2

    Use Vite's Import Meta for HTML

    Instead of directly accessing environment variables in `index.html`, use Vite's `import.meta.env` in your JavaScript files. This allows you to conditionally render HTML based on environment variables.

    javascript
    if (import.meta.env.VITE_VARIABLE_NAME === 'true') {
      // Insert your HTML tag logic here
    }
  3. 3

    Update HTML Template with Script Tag

    Ensure that your `index.html` includes a script tag that loads the JavaScript file where you handle the conditional rendering based on the environment variable.

    html
    <script type="module" src="/path/to/your/script.js"></script>
  4. 4

    Test in Development and Production

    Run the Vite development server and build the project to ensure that the environment variables are correctly accessed in both environments. Check the console for any errors.

    bash
    npm run dev && npm run build
  5. 5

    Verify Environment Variable Injection

    Inspect the built HTML file to confirm that the expected HTML tags are conditionally rendered based on the environment variable values.

    html
    Open the built index.html and check for the presence of the expected elements.

Validation

Confirm that the HTML elements are rendered correctly based on the environment variable values in both development and production builds. Check for any console errors related to environment variable access.

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Environment

Submitted by

AC

Alex Chen

2450 rep

Tags

vitebuild-tooljavascriptenhancementfeat:-html