cf-proxy Setup Guide

The cf-proxy tool simplifies the connection between local applications and remote services hosted on SAP BTP. It enables developers to deploy applications to SAP BTP via Cloud Foundry, set up a local proxy to route requests securely, and integrate XSUAA and Destination services for authentication and connectivity. Additionally, it supports creating SSH tunnels for secure access to remote resources. This tool is particularly useful for testing, debugging, and securely interacting with cloud services directly from a local environment.

This guide provides instructions for setting up and configuring a local proxy to connect with a remote cf-proxy service. By following the steps outlined below, you will:

• Set environment variables for proxy usage.
• Install the project dependencies.
• Configure scripts and bindings for XSUAA and proxy startup.

Ensure to have Node.js and npm installed before proceeding.

Deploy the remote application to SAP BTP

The remote application is already available in the /remote folder. Follow these steps to deploy it to SAP Business Technology Platform (BTP):

Prerequisites

1. SAP BTP Access: Ensure you have access to a subaccount and space in SAP BTP.
2. Cloud Foundry CLI: Install the Cloud Foundry CLI and authenticate to your BTP environment.
3. Pre-configured Services: Ensure the required services (e.g., XSUAA, destination service) are already created in your BTP subaccount.
4. Node.js Environment: The application uses Node.js—make sure Node.js is supported in the configured buildpacks.

Steps to Deploy the proxy endpoint

1. Navigate to the /remote Folder

Open a terminal and navigate to the remote application folder:

cd remote

2. Login to SAP BTP Cloud Foundry

Log in to the Cloud Foundry environment using the following command:

cf login -a <API_ENDPOINT> -o <ORG> -s <SPACE> --sso

Replace:

• <API_ENDPOINT>: Your BTP API endpoint (e.g., https://api.cf.<region>.hana.ondemand.com).
• <ORG>: Your organization name in BTP.
• <SPACE>: Your space name in BTP.

If additional configuration is needed, modify the file accordingly.

3. Deploy the Application

Deploy the remote app to SAP BTP using the following command:

npm run deploy

The npm run deploy command will:

• Build the application from the /remote folder.
• Upload the application.
• Bind any configured services from the manifest.yml.
• Start the application in your specified space.

4. Verify Deployment

Once the deployment completes:

• Go to the SAP BTP Cockpit.
• Navigate to your subaccount → space → applications.
• Verify that the application (e.g., remote-app) is running.

5. Access the Application

Copy the application URL from the BTP cockpit or the CLI output. For example:

https://remote-app.<region>.cfapps.<landscape>.hana.ondemand.com

Use this URL to access the remote application.

Optional Steps

• Service Bindings: If you need to bind new services to the existing application, use the cf bind-service command:

cf bind-service remote-app <SERVICE-NAME>
cf restage remote-app

• Log Monitoring: Check logs if the deployment encounters issues:

cf logs remote-app --recent

Summary

Navigate to the /remote folder and execute cf push. The application should be deployed and accessible in your defined SAP BTP space.

Setting Up local Proxy

Installation

First, install the necessary dependencies:

npm install -g .

Create .env File

Create a .env file in the root directory, which binds the proxy to a remote service:

cf-proxy bind https://cf-proxy.cfapps.eu10.hana.ondemand.com

Replace https://cf-proxy.cfapps.eu10.hana.ondemand.com with the URL of your SAP BTP destination proxy's endpoint.

Adding Start Script for Proxy

To start the proxy locally, add the following to your app/package.json file’s scripts section:

"proxy": "cf-proxy run"

XSUAA Binding Configuration

If you use XSUAA services, include the binding script in the root package.json:

"bind:xsuaa": "npx cds-ts bind uaa --to XSUAA-RESOURCE-NAME --kind xsuaa --for hybrid"

Replace XSUAA-RESOURCE-NAME with the name of your XSUAA service instance. This binds your application securely to the respective resource.

Add proxy environment variables

Windows

set http_proxy=http://127.0.0.1:8887
set https_proxy=http://127.0.0.1:8887
set all_proxy=http://127.0.0.1:8887

Linux

export http_proxy=http://127.0.0.1:8887
export https_proxy=http://127.0.0.1:8887
export all_proxy=http://127.0.0.1:8887

Next Steps

Once all steps are completed, you can:

1. Run the proxy using npm run proxy.
2. Test your application to ensure proxy settings are applied correctly.
3. Refer to the official documentation for additional features or advanced configurations.

Starting and Stopping an SSH Tunnel

An SSH tunnel establishes a secure connection between your local machine and a remote host—useful for accessing resources through a Cloud Foundry application. The cf-proxy utility provides commands to easily start and stop an SSH tunnel.

Start the SSH Tunnel

To start the SSH tunnel, use the following command:

cf-proxy sshTunnel:start <cf_app> <remote_host> [port]

• <cf_app>: The name of the Cloud Foundry application.
• <remote_host>: The hostname or IP address of the remote server you want to connect to.
• [port] (optional): The local port for the SSH tunnel. Defaults to 1348 if not specified.

Stop the SSH Tunnel

To stop the SSH tunnel running on a specific local port, use the following command:

cf-proxy sshTunnel:stop --port <port>

• <port>: The local port on which the SSH tunnel is running.