ChieloNewctle / k8s-webterm-connector

A simple demo to bind a TCP port with k8s exec channel.k8s.io websocket API.

k8s-webterm-connector

Tired with web terminals? Let's use it with CLI!

This is just a simple demo to bind a TCP port with k8s exec websocket API, which use channel.k8s.io as subprotocol.

You can tweak it to suit your needs.

Usage

cargo run <tcp-address-to-bind> [websocket-url|file-url]

You can also use the latest release instead of cargo run.

WebSocket URL Example

For example, bind 127.0.0.1:27730 with wss://example.com/k8s-pod/exec?token=TOKEN:

cargo run 127.0.0.1:27730 'wss://example.com/k8s-pod/exec?token=TOKEN'

Keep it running, and then you can test it with:

socat - tcp:127.0.0.1:27730

File URL Example

For example, a file in /tmp/k8s-webterm-connector-ws-27730-url.txt contains the websocket URL:

wss://example.com/k8s-pod/exec?token=TOKEN

Then you can bind 127.0.0.1:27730 to the webterm URL in that file with:

cargo run 127.0.0.1:27730 file:///tmp/k8s-webterm-connector-ws-27730-url.txt

Keep it running, and then you can test it with:

socat - tcp:127.0.0.1:27730

SSH via k8s-webterm-connector

As long as an IO method exists, you can use it for SSH conneciton.

socat and openssh-server should be installed in the image of the target containers.

You can use tools/proxy-ssh-via-k8s-webterm.sh as ProxyCommand in your ~/.ssh/config.

Host <hostname-you-like>
  ProxyCommand <...>/k8s-webterm-connector/tools/proxy-ssh-via-k8s-webterm.sh %p <ssh-port-inside-container>
  Port <connector-bind-port>
  HostName <any-valid-hostname>
  User <username-in-container>
  ServerAliveInterval 15
  StrictHostKeyChecking no

Example

For example, k8s-webterm-connector is running and binds 27730. Inside the target container, 10022 TCP port is available or used for SSH.

Host k8s-container
  ProxyCommand ~/k8s-webterm-connector/tools/proxy-ssh-via-k8s-webterm.sh %p 10022
  Port 27730
  HostName container
  User root
  ServerAliveInterval 15
  StrictHostKeyChecking no

Then you can ssh into the container:

ssh k8s-container

Multiplex SSH via k8s-webterm-connector and port forwarding

This tool wraps tools/proxy-ssh-via-k8s-webterm.sh and forward SSH port to the local machine.

It will be more stable if URL to the webterm is constantly changing, but less efficient as only one connection is created.

./tools/k8s-webterm-ssh-forward.sh <k8s-webterm-connector-bind-port> <pod-ssh-port> <forward-ssh-bind-port>

socat and openssh-server should be installed in the image of the target containers.

Example

For example, k8s-webterm-connector is running and binds 27730. Inside the target container, 10022 TCP port is available or used for SSH. And you would like to use SSH locally to connect the container on 27731.

./tools/k8s-webterm-ssh-forward.sh 27730 10022 27731

Keep it running, and then you can ssh to the container:

ssh -p 27731 USERNAME-IN-CONTAINER@127.0.0.1