ENV for React Native

.env

# Here's a comment
TEST=test
API=http://www.example.com/api


NUMBER=1

Config.swift

import Foundation

@objc(Config)
class Config: NSObject {
  @objc static func requiresMainQueueSetup() -> Bool {
    return false
  }

  @objc var constantsToExport: [String: Any] {
    return Environment.values
  }
}

env.android.sh

# #!/bin/bash
set -euo pipefail

ENV_NAME="${1:-dev}"
ENV_FILE=".env.$ENV_NAME"
APP_NAME=test

if [ ! -f "$ENV_FILE" ]; then
  echo "⚠️  No env file found at $ENV_FILE"
  exit 1
fi

# Generate Android Environment.kt
ANDROID_OUTPUT="android/app/src/main/java/com/$APP_NAME/Environment.kt"
mkdir -p "$(dirname "$ANDROID_OUTPUT")"

cat <<EOF > "$ANDROID_OUTPUT"
// Generated automatically from $ENV_FILE - do not edit
package com.$APP_NAME

object Environment {
  val values: Map<String, String> = mapOf(
EOF

grep -Ev '^(#|[[:space:]]*$)' "$ENV_FILE" | while IFS='=' read -r key value; do
  key_trimmed=$(echo "$key" | xargs)
  value_trimmed=$(echo "$value" | xargs)
  value_escaped=$(printf '%s' "$value_trimmed" | sed 's/"/\\"/g')

  echo "    \"$key_trimmed\" to \"$value_escaped\"," >> "$ANDROID_OUTPUT"
done

echo "  )" >> "$ANDROID_OUTPUT"
echo "}" >> "$ANDROID_OUTPUT"
echo "✅ Android Environment.kt generated for $ENV_NAME"

env.ios.sh

#!/bin/bash

set -euo pipefail

# Get the env file for the configuration lowercased
ENV_FILE="$SRCROOT/../.env.${CONFIGURATION,,}"

if [ ! -f "$ENV_FILE" ]; then
  echo "⚠️  No env file found at $ENV_FILE"
  exit 0
fi

OUTPUT_FILE="$SRCROOT/Environment.swift"
echo "Generating $OUTPUT_FILE from $ENV_FILE"

# Start the Swift file
cat <<EOF > "$OUTPUT_FILE"
// Generated automatically from $ENV_FILE — do not edit.

@objcMembers
class Environment: NSObject {
  static let values: [String: Any] = [
EOF

# Grab every non-comment, non-empty line
# Sort by the key and iterate over the values
# adding a line to the environment
grep -Ev '^(#|[[:space:]]*$)' "$ENV_FILE" | sort | while IFS='=' read -r key value; do
  key_trimmed=$(echo "$key" | xargs)
  value_trimmed=$(echo "$value" | xargs)

  # Escape double quotes inside value
  value_escaped=$(printf '%s' "$value_trimmed" | sed 's/"/\\"/g')

  # Generate a line in the Swift dictionary
  echo "    \"$key_trimmed\" : \"$value_escaped\"" >> "$OUTPUT_FILE"
done

# Close file
echo "  ]
}" >> "$OUTPUT_FILE"
echo "✅ Generated $OUTPUT_FILE"

Environment.kt

// Generated automatically from .env.dev - do not edit
package com.myapp

object Environment {
  val values: Map<String, String> = mapOf(
    "TEST" to "test",
    "API" to "http://www.example.com/api",
    "NUMBER" to "1",
  )
}

Environment.swift

// Generated automatically from .env — do not edit.

@objcMembers
class Environment: NSObject {
  static let values: [String: Any] = [
    "API" : "http://www.example.com/api"
    "NUMBER" : "1"
    "TEST" : "test"
  ]
}