intermediate_nodejs_server

An intermediate Node.js server to make CORS requests with Tailscale networking.

This repository contains two main components:

1. Intermediate Server: A simple Express server project that gets requests (json files from other servers that need specific headers) from external clients and returns the result.
2. Tailscale Service: A Tailscale client that creates a secure network connection when deployed to Balena, allowing remote access to your server.

The Express server is usually referred to as an intermediate server.

A use case scenario is that you have created an only client web app and you need to make requests to outside servers that need some headers. Because you have only a client side you can't do those requests by yourself. Thus, you need an intermediate server.

Example

You need to get the basic details of a package that is published to npm. You can get this by the following link.

http://registry.npmjs.org/localforage/latest

This request requires CORS Preflight, which can only be done by servers.

The solution to this problem is to use an intermediate server.

With the code on this repository you can create and deploy a node server to serve this purpose.

Thus, after the deployment your client can take the needed data with the following link:

"http://my_intermediate_server.com/http://registry.npmjs.org/localforage/latest"

Get started

1. Clone project

$ git clone https://github.com/Temeteron/intermediate-nodejs-server.git

2. Customize server, start with:

$ nvm use 12
$ npm run start

3. Deploy

Create an .env file in the root directory of the project with the following content:

# your balena project name
PROJECT_NAME=${profile_name/project_name}

You can deploy your server to GCP or any other site you prefer. You can also deploy your server to a Raspberry Pi, if you have one. This can be done easily if you use Balena. You can find a full tutorial about balena here.

Balena Deployment with Tailscale

When deploying to Balena, this project includes a Tailscale service that allows secure remote access to your intermediate server. The deployment includes:

• Node.js Express Server: The main intermediate server for handling CORS requests
• Tailscale Client: Provides secure networking and remote access capabilities

Required Environment Variables for Balena

Set these variables in your Balena dashboard:

# Tailscale authentication key (get from https://login.tailscale.com/admin/settings/keys)
TS_AUTHKEY=tskey-auth-xxxxxxxxxxxxxxxx

# Optional: Custom hostname for your device
TS_HOSTNAME=my-intermediate-server

# Scan for subnet routes (192.168.1.0/24)
TS_ROUTES=192.168.1.0/24

# To accept routes from other devices (usually not needed)
TS_ACCEPT_ROUTES=true

After deployment, your intermediate server will be accessible via:

• Local network (if connected to same WiFi)
• Tailscale network (from any device connected to your Tailscale account)

$ npm run deploy

Test tailscale speed

Server upload speed

Command

# Upload 5Mb from server to client
-c ${server-ip-address} -i 5 -n 5000.00k -4 -R

Result (3.58 Mbps, depends on server's upload speed)

[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  5.00 MBytes  41.9 Mbits/sec    0   1.12 MBytes
[  5]   1.00-2.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   2.00-3.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   3.00-4.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   4.00-5.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   5.00-6.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   6.00-7.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   7.00-8.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   8.00-9.00   sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]   9.00-10.00  sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]  10.00-11.00  sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
[  5]  11.00-11.73  sec  0.00 Bytes  0.00 bits/sec    0   1.12 MBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-11.73  sec  5.00 MBytes  3.58 Mbits/sec    0             sender

Client upload speed (server download speed)

# Upload 5Mb from client to server (server downloads the file)
-c ${server-ip-address} -i 5 -n 5000.00k -4

Result (14.7 Mbps, depends on client's upload speed)

[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  1.21 MBytes  10.1 Mbits/sec
[  5]   1.00-2.00   sec  2.29 MBytes  19.2 Mbits/sec
[  5]   2.00-2.04   sec  77.9 KBytes  17.4 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-2.04   sec  3.57 MBytes  14.7 Mbits/sec                  receiver