Environment Validation

Overview

Envark’s validation feature ensures your .env files contain all the environment variables your code actually uses, with proper values. It catches configuration errors before deployment by comparing your .env files against real code usage.

Quick Start

# Validate default .env file
envark validate

# Validate specific file
envark validate .env.production

# Validate relative to project directory
envark validate ../config/.env --project /path/to/project

How Validation Works

Validation follows a three-step process:

1. Scan Codebase

Envark scans your project to discover all environment variables used in code:

// From src/tools/validate_env_file.ts:123-126
const scanResult = scanProject(projectPath);
const resolved = resolveEnvMap(scanResult.usages);

2. Parse .env File

Parse the target .env file to extract defined variables:

// From src/tools/validate_env_file.ts:74-99
function parseEnvFileContent(content: string): Map<string, string> {
    const vars = new Map<string, string>();

    for (const line of content.split('\n')) {
        const trimmed = line.trim();

        // Skip comments and empty lines
        if (!trimmed || trimmed.startsWith('#')) continue;

        // Parse KEY=VALUE
        const match = trimmed.match(/^(?:export\s+)?([A-Z][A-Z0-9_]*)=(.*)$/);
        if (match && match[1]) {
            let value = match[2] || '';

            // Remove quotes
            if ((value.startsWith('"') && value.endsWith('"')) ||
                (value.startsWith("'") && value.endsWith("'"))) {
                value = value.slice(1, -1);
            }

            vars.set(match[1], value);
        }
    }

    return vars;
}

3. Compare & Validate

Cross-reference to identify issues:

Missing Variables: Used in code but not in .env
Unused Variables: In .env but never used
Empty Values: Variables with no value
Placeholder Values: Variables with dummy values

Validation Statuses

Pass

Variable is properly configured:

Present in .env file
Has a real value
Used in code

Warning

Non-critical issue:

Defined but not used
Missing but has default value
Informational notices

Fail

Critical problem:

Missing from .env
Empty value
Placeholder value

Validation Checks

Missing Variables

Variables used in code but not defined in the .env file:

// From src/tools/validate_env_file.ts:186-207
for (const varName of usedInCode) {
    if (!envVars.has(varName)) {
        // Check if it has a default value in code
        const variable = resolved.variables.get(varName);
        if (variable && !variable.hasDefault) {
            failed.push({
                variable: varName,
                status: 'fail',
                issue: 'Used in code but missing from env file',
                suggestion: 'Add this variable to your env file'
            });
        } else if (variable?.hasDefault) {
            warnings.push({
                variable: varName,
                status: 'warning',
                issue: 'Used in code but missing from env file (has default)',
                suggestion: 'Consider adding explicitly for clarity'
            });
        }
    }
}

Example:

// src/config.ts
const dbUrl = process.env.DATABASE_URL;  // ✗ FAIL: Missing from .env

Unused Variables

Variables defined in .env but never referenced in code:

// From src/tools/validate_env_file.ts:141-151
if (!usedInCode.has(varName)) {
    warnings.push({
        variable: varName,
        status: 'warning',
        issue: 'Defined in env file but never used in code',
        suggestion: "Remove if not needed, or verify it's used indirectly",
        value: value.length > 20 ? value.slice(0, 20) + '...' : value
    });
    continue;
}

Example:

# .env
OLD_API_KEY=abc123  # ⚠ WARNING: Not used anywhere

Empty Values

Variables with no value assigned:

// From src/tools/validate_env_file.ts:154-163
if (value.trim() === '') {
    failed.push({
        variable: varName,
        status: 'fail',
        issue: 'Empty value',
        suggestion: 'Set a valid value or remove if not needed',
        value: '(empty)'
    });
    continue;
}

Example:

# .env
API_KEY=        # ✗ FAIL: Empty value
DEBUG_MODE=""   # ✗ FAIL: Empty string

Placeholder Values

Variables with obvious dummy values that need replacement:

// From src/tools/validate_env_file.ts:50-61
const PLACEHOLDER_PATTERNS = [
    /^changeme$/i,
    /^your[_-]?(key|token|secret|password)/i,
    /^xxx+$/i,
    /^todo$/i,
    /^fixme$/i,
    /^replace[_-]?me$/i,
    /^placeholder$/i,
    /^<.*>$/,
    /^\[.*\]$/,
    /^example$/i,
];

function isPlaceholder(value: string): boolean {
    return PLACEHOLDER_PATTERNS.some(p => p.test(value.trim()));
}

Detected Placeholders:

Common
TODO/FIXME
Brackets
Generic

API_KEY=changeme
SECRET=your-key-here
TOKEN=your_token_here
PASSWORD=xxx

DATABASE_URL=todo
API_ENDPOINT=fixme
SECRET_KEY=replace-me

API_KEY=<your-api-key>
TOKEN=[your-token]
URL=<insert-url-here>

SECRET=placeholder
KEY=example
VALUE=test

Validation Output

CLI Output

$ envark validate .env

┌─ VALIDATION ──────────────────────────────────────────────┐
│  Status: ✗ INVALID
│  Passed: 35  Warnings: 3  Failed: 4
└──────────────────────────────────────────────────────────┘

✓ PASSED (35)
  DATABASE_URL              postgresql://...
  API_KEY                   sk-abc...
  PORT                      3000
  ...

⚠ WARNINGS (3)
  OLD_FEATURE_FLAG          Defined but never used in code
  LEGACY_API_URL            Defined but never used in code
  BACKUP_ENABLED            Missing from file (has default)

✗ FAILED (4)
  SECRET_KEY                Empty value
  STRIPE_KEY                Placeholder: "your-key-here"
  DATABASE_PASSWORD         Missing from env file
  REDIS_URL                 Missing from env file

RECOMMENDATIONS:
  • Set a value for SECRET_KEY
  • Replace placeholder in STRIPE_KEY with actual key
  • Add DATABASE_PASSWORD and REDIS_URL to .env
  • Consider removing unused OLD_FEATURE_FLAG and LEGACY_API_URL

TUI Output

# In interactive mode
/validate .env
v .env.production

JSON Output

$ envark validate --json

{
  "valid": false,
  "envFilePath": ".env",
  "results": {
    "passed": [
      {
        "variable": "DATABASE_URL",
        "status": "pass",
        "value": "postgresql://..."
      }
    ],
    "warnings": [
      {
        "variable": "OLD_FEATURE_FLAG",
        "status": "warning",
        "issue": "Defined in env file but never used in code",
        "suggestion": "Remove if not needed"
      }
    ],
    "failed": [
      {
        "variable": "SECRET_KEY",
        "status": "fail",
        "issue": "Empty value",
        "suggestion": "Set a valid value"
      }
    ]
  },
  "summary": {
    "total": 42,
    "passed": 35,
    "warnings": 3,
    "failed": 4,
    "unusedInFile": 2,
    "missingFromFile": 2
  }
}

Validation Result Structure

// From src/tools/validate_env_file.ts:25-47
export interface ValidateEnvFileOutput {
    valid: boolean;                    // Overall pass/fail
    envFilePath: string;               // Path to validated file
    results: {
        passed: ValidationEntry[];     // Variables that passed
        warnings: ValidationEntry[];   // Non-critical issues
        failed: ValidationEntry[];     // Critical failures
    };
    summary: {
        total: number;                 // Total vars in .env
        passed: number;                // Count passed
        warnings: number;              // Count warnings
        failed: number;                // Count failed
        unusedInFile: number;          // Defined but unused
        missingFromFile: number;       // Used but not defined
    };
    metadata: {
        projectPath: string;
        scannedFiles: number;
        cacheHit: boolean;
        duration: number;
    };
}

Use Cases

Pre-Deployment Validation

#!/bin/bash
# deploy.sh

echo "Validating environment configuration..."
envark validate .env.production --fail-on-errors

if [ $? -eq 0 ]; then
    echo "✓ Environment validated successfully"
    npm run build
    npm run deploy
else
    echo "✗ Environment validation failed"
    exit 1
fi

Multiple Environment Validation

# Validate all environment files
envark validate .env
envark validate .env.development
envark validate .env.staging
envark validate .env.production

CI/CD Integration

# .github/workflows/validate-env.yml
name: Validate Environment Files

on:
  push:
    paths:
      - '.env*'
      - 'src/**'

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      
      - name: Install Envark
        run: npm install -g envark
      
      - name: Validate Development Environment
        run: envark validate .env.example
      
      - name: Check for Critical Issues
        run: |
          envark validate .env.example --json > validation.json
          FAILED=$(jq '.summary.failed' validation.json)
          if [ "$FAILED" -gt 0 ]; then
            echo "❌ Found $FAILED critical validation issues"
            exit 1
          fi

Docker Build Validation

# Dockerfile
FROM node:18-alpine

WORKDIR /app

# Install Envark
RUN npm install -g envark

# Copy source and env files
COPY . .

# Validate before building
RUN envark validate .env.production --fail-on-errors

# Build application
RUN npm run build

CMD ["npm", "start"]

CLI Options

envark validate [env-file] [options]

Options:
  --project <path>        Project directory to scan (default: current directory)
  --fail-on-errors        Exit with code 1 if validation fails
  --fail-on-warnings      Exit with code 1 if warnings found
  --json                  Output results as JSON
  --quiet                 Only show summary
  --verbose               Show detailed information

Programmatic Usage

import { validateEnvFile } from 'envark';

const result = await validateEnvFile({
    envFilePath: '.env.production',
    projectPath: '/path/to/project'
});

if (!result.valid) {
    console.error('Validation failed!');
    
    // Log critical failures
    for (const failure of result.results.failed) {
        console.error(`✗ ${failure.variable}: ${failure.issue}`);
        console.error(`  Suggestion: ${failure.suggestion}`);
    }
    
    process.exit(1);
}

console.log(`✓ All ${result.summary.passed} variables validated successfully`);

Best Practices

Validate Before Deploy

Always validate production .env files before deployment to catch configuration errors early.

Use .env.example

Maintain .env.example as a template and validate it in CI to ensure documentation is current.

Environment Parity

Validate all environment files (.env.development, .env.staging, .env.production) to ensure consistency.

Automate Checks

Add validation to CI/CD pipelines, pre-commit hooks, and deployment scripts.

Common Issues and Solutions

False positives for dynamic access

Issue: Envark reports variables as unused when accessed dynamically:

const key = 'API_KEY';
const value = process.env[key];  // Dynamic access

Solution: Add a comment or explicitly reference variables:

// Required env vars: API_KEY, SECRET_KEY, DATABASE_URL
const value = process.env[key];

Variables used in external tools

Issue: Variables used by Docker, shell scripts, or external tools aren’t detected.Solution:

Document external usage in comments
Add to .env.example with explanatory notes
Consider these as warnings rather than failures

Default values cause warnings

Issue: Variables with defaults in code show as warnings when missing from .env.Solution: This is expected behavior. You can:

Add them to .env explicitly for clarity
Accept the warning as informational
Use --fail-on-warnings=false in automation

Exit Codes

- Validation passed (or only warnings if --fail-on-warnings not set)
- Validation failed (critical issues found)
- Invalid arguments or file not found

Risk Analysis - Analyze security risks in your environment variables
Scanning - Discover all environment variables in your project
AI Assistant - Get AI-powered recommendations for your configuration

Implementation Details

The validation engine is implemented in:

src/tools/validate_env_file.ts: Main validation logic (lines 104-236)
src/core/scanner.ts: Codebase scanning
src/core/resolver.ts: Variable resolution

See src/tools/validate_env_file.ts:104-236 for the complete validation implementation.

Get Started

Core Features

CLI Reference

MCP Integration

Guides

​Overview

​Quick Start

​How Validation Works

​1. Scan Codebase

​2. Parse .env File

​3. Compare & Validate

​Validation Statuses

Pass

Warning

Fail

​Validation Checks

​Missing Variables

​Unused Variables

​Empty Values

​Placeholder Values

​Validation Output

​CLI Output

​TUI Output

​JSON Output

​Validation Result Structure

​Use Cases

​Pre-Deployment Validation

​Multiple Environment Validation

​CI/CD Integration

​Docker Build Validation

​CLI Options

​Programmatic Usage

​Best Practices

Validate Before Deploy

Use .env.example

Environment Parity

Automate Checks

​Common Issues and Solutions

​Exit Codes

​Related Features

​Implementation Details

Build docs developers (and LLMs) love

Overview

Quick Start

How Validation Works

1. Scan Codebase

2. Parse .env File

3. Compare & Validate

Validation Statuses

Validation Checks

Missing Variables

Unused Variables

Empty Values

Placeholder Values

Validation Output

CLI Output

TUI Output

JSON Output

Validation Result Structure

Use Cases

Pre-Deployment Validation

Multiple Environment Validation

CI/CD Integration

Docker Build Validation

CLI Options

Programmatic Usage

Best Practices

Common Issues and Solutions

Exit Codes

Related Features

Implementation Details