add a tutorial for using CLI with an http proxy (#169)

docs.kosli.com/content/tutorials/cli_and_http_proxy.md

@@ -0,0 +1,62 @@
+---
+title: "Using Kosli CLI with an HTTP proxy"
+bookCollapseSection: false
+weight: 511
+---
+
+# Using Kosli CLI with an HTTP proxy
+
+In enterprises with strict network policies, you might want to communicate with Kosli via an HTTP proxy as the single point of egress communication with Kosli. 
+
+This tutorial shows how you can setup an HTTP proxy and use it when communicating with Kosli via the CLI.
+
+## TLDR
+
+If you already have an HTTP proxy, [start using it with Kosli CLI](#use-the-http-proxy-with-kosli-cli)
+
+
+{{<hint info>}}
+In this tutorial, we will setup Tinyproxy (in docker) as an HTTP proxy on a Mac machine.
+The same steps apply for different HTTP proxies and machines, but commands will differ.
+{{</hint>}}
+
+
+## Start the HTTP proxy
+
+1. Start Tinyproxy using docker:
+
+```shell {.command}
+$ cat <<EOF > tinyproxy.conf
+User nobody
+Group nobody
+Port 8888
+EOF
+
+$ docker run -p 8888:8888 -v $(PWD)/tinyproxy.conf:/etc/tinyproxy/tinyproxy.conf:ro kalaksi/tinyproxy
+```
+
+
+
+Now you have an HTTP proxy running at http://localhost:8888
+
+## Use the HTTP proxy with Kosli CLI
+
+To verify if the setup works, you can run this command to list environments of the public demo org `Cyber Dojo`:
+
+```shell {.command}
+$ kosli list envs --org cyber-dojo --http-proxy http://localhost:8888 --api-token <<your-token>>
+```
+
+Your request goes through the HTTP proxy and is then forwarded to Kosli. If successful, you should see a similar output to this:
+
+```
+NAME                         TYPE  LAST REPORT                LAST MODIFIED              TAGS
+aws-beta                     ECS   2024-04-18T15:17:54+02:00  2024-04-18T15:17:54+02:00  [url=https://beta.cyber-dojo.org/]
+aws-prod                     ECS   2024-04-18T15:17:57+02:00  2024-04-18T15:17:57+02:00  [url=https://cyber-dojo.org/]
+terraform-state-differ-beta  S3    2024-04-18T15:18:23+02:00  2024-04-18T15:18:23+02:00  
+terraform-state-differ-prod  S3    2024-04-18T15:18:17+02:00  2024-04-18T15:18:17+02:00 
+```
+
+All you need to do now is to use `--http-proxy http://localhost:8888` with your CLI commands.
+Alternatively, you can add this to your kosli config so that you don't type it on each command:
+`kosli config --http-proxy=http://localhost:8888`