Script to start ngrok, copy the generated URL to clipboard and update a remote Cloudflare worker with the public ngrok url

start_ngrok_update_cloudflare.sh

#!/usr/bin/env bash
echo "=========== START LOCAL HTTP / HTTPS TUNNEL AND UPDATE YOUR REMOTE DEV DOMAIN TO POINT IT ==========="
printf "\n"

# Start NGROK in background
echo "⚡️ Starting ngrok"
ngrok http 8080 > /dev/null &

# Wait for ngrok to be available
while ! nc -z localhost 4040; do
  sleep 1/5 # wait Ngrok to be available
done

# Get NGROK dynamic URL from its own exposed local API
NGROK_REMOTE_URL="$(curl -s http://localhost:4040/api/tunnels | jq ".tunnels[0].public_url")"
if test -z "${NGROK_REMOTE_URL}"
then
  echo "❌ ERROR: ngrok doesn't seem to return a valid URL (${NGROK_REMOTE_URL})."
  exit 1
fi

# Trim double quotes from variable
NGROK_REMOTE_URL=$(echo ${NGROK_REMOTE_URL} | tr -d '"')
# If http protocol is returned, replace by https
NGROK_REMOTE_URL=${NGROK_REMOTE_URL/http:\/\//https:\/\/}

# Get script parent folder to point to .env file and get TELEGRAM_BOT_TOKEN dynamically
PARENT_PATH=$( cd "$(dirname "${BASH_SOURCE[0]}")" || exit ; pwd -P )

# Get TELEGRAM_BOT_TOKEN dynamically from local .env file
TELEGRAM_BOT_TOKEN=$(grep TELEGRAM_BOT_TOKEN ${PARENT_PATH}/../.env.local | cut -d '=' -f2)
if test -z "${TELEGRAM_BOT_TOKEN}"
then
  echo "❌ ERROR: I haven't been able to recover TELEGRAM_BOT_TOKEN from your local .env.local variables file."
  exit 1
fi

# Get CLOUDFLARE_ACCOUNT_ID dynamically from local .env file
CLOUDFLARE_ACCOUNT_ID=$(grep CLOUDFLARE_ACCOUNT_ID ${PARENT_PATH}/../.env.local | cut -d '=' -f2)
if test -z "${CLOUDFLARE_ACCOUNT_ID}"
then
  echo "❌ ERROR: I haven't been able to recover CLOUDFLARE_ACCOUNT_ID from your local .env.local variables file."
  exit 1
fi

# Get CLOUDFLARE_WORKERS_AUTH_BEARER dynamically from local .env file
CLOUDFLARE_WORKERS_AUTH_BEARER=$(grep CLOUDFLARE_WORKERS_AUTH_BEARER ${PARENT_PATH}/../.env.local | cut -d '=' -f2)
if test -z "${CLOUDFLARE_WORKERS_AUTH_BEARER}"
then
  echo "❌ ERROR: I haven't been able to recover CLOUDFLARE_WORKERS_AUTH_BEARER from your local .env.local variables file."
  exit 1
fi

# Get CLOUDFLARE_LOCAL_WORKER dynamically from local .env file
CLOUDFLARE_LOCAL_WORKER=$(grep CLOUDFLARE_LOCAL_WORKER ${PARENT_PATH}/../.env.local | cut -d '=' -f2)
if test -z "${CLOUDFLARE_LOCAL_WORKER}"
then
  echo "❌ ERROR: I haven't been able to recover CLOUDFLARE_LOCAL_WORKER from your local .env.local variables file."
  exit 1
fi

# Get CLOUDFLARE_LOCAL_URL dynamically from local .env file
CLOUDFLARE_LOCAL_URL=$(grep CLOUDFLARE_LOCAL_URL ${PARENT_PATH}/../.env.local | cut -d '=' -f2)
if test -z "${CLOUDFLARE_LOCAL_URL}"
then
  echo "❌ ERROR: I haven't been able to recover CLOUDFLARE_LOCAL_URL from your local .env.local variables file."
  exit 1
fi

printf "\n"
echo "⚡️ Updating Cloudflare worker to allow dynamic tunneling from"
echo "   ${CLOUDFLARE_LOCAL_URL} 👉 ${NGROK_REMOTE_URL}"
# Update Cloudflare Worker
curl -s -X PUT "https://api.cloudflare.com/client/v4/accounts/${CLOUDFLARE_ACCOUNT_ID}/workers/scripts/${CLOUDFLARE_LOCAL_WORKER}" \
     -H "Authorization: Bearer ${CLOUDFLARE_WORKERS_AUTH_BEARER}" \
     -H "Content-Type: application/javascript" \
     --data "addEventListener('fetch', event => {
    const request = event.request
    const path = request.url.replace(/^https?:\/\/.*?\//gi, '/');
    const modifiedRequest = new Request('${NGROK_REMOTE_URL}'.concat(path), request)
    return event.respondWith(fetch(modifiedRequest));
})" > /dev/null &

echo ${NGROK_REMOTE_URL} | tr -d '\n' | pbcopy
printf "\n"
echo "📋 I've just copied your ngrok remote URL to your clipboard 😉"
printf "\n"

exit 0

Thanks a ton for sharing this!