docs update, added setup scripts

docs/docker.md

@@ -0,0 +1,63 @@
+# Getting started with `go-proxy` docker container
+
+## Setup
+
+1. Install `wget` if not already
+
+2. Run setup script
+
+   `bash <(wget -qO- https://6uo.me/go-proxy-setup-docker)`
+
+   What it does:
+
+   - Create required directories
+   - Setup `config.yml` and `compose.yml`
+
+3. Verify folder structure
+
+    ```plain
+    go-proxy
+    ├── certs
+    ├── compose.yml
+    └── config
+        ├── config.yml
+        └── providers.yml
+    ```
+
+4. Enable HTTPs _(optional)_
+   - To use autocert feature
+     - completing `autocert` section in `config/config.yml`
+     - mount `certs/` to `/app/certs` to store obtained certs
+
+   - To use existing certificate
+
+     mount your wildcard (`*.y.z`) SSL cert
+
+     - cert / chain / fullchain -> `/app/certs/cert.crt`
+     - private key -> `/app/certs/priv.key`
+
+5. Modify `compose.yml` fit your needs
+
+    Add networks to make sure it is in the same network with other containers, or make sure `proxy.<alias>.host` is reachable
+
+6. Run `docker compose up -d` to start the container
+
+7. Start editing config files in `http://<ip>:8080`
+
+## Troubleshooting
+
+- Firewall issues
+
+    If you are using `ufw` with vpn that drop all inbound traffic except vpn, run below:
+
+    `sudo ufw allow from 172.16.0.0/16 to 100.64.0.0/10`
+
+    Explaination:
+
+    Docker network is usually `172.16.0.0/16`
+
+    Tailscale is used as an example, `100.64.0.0/10` will be the CIDR
+
+    You can also list CIDRs of all docker bridge networks by:
+
+    `docker network inspect $(docker network ls | awk '$3 == "bridge" { print $1}') | jq -r '.[] | .Name + " " + .IPAM.Config[0].Subnet' -`