feat: Allow local certificates to be used by Caddy

docs/tls.md

@@ -0,0 +1,38 @@
+# TLS Certificates
+
+## Trusting the Authority
+
+With a standard installation, the authority used to sign certificates generated in the Caddy container is not trusted by your local machine.
+You must add the authority to the trust store of the host :
+
+```
+# Mac
+$ docker cp $(docker compose ps -q caddy):/data/caddy/pki/authorities/local/root.crt /tmp/root.crt && sudo security add-trusted-cert -d -r trustRoot -k /Library/Keychains/System.keychain /tmp/root.crt
+# Linux
+$ docker cp $(docker compose ps -q caddy):/data/caddy/pki/authorities/local/root.crt /usr/local/share/ca-certificates/root.crt && sudo update-ca-certificates
+# Windows
+$ docker compose cp caddy:/data/caddy/pki/authorities/local/root.crt %TEMP%/root.crt && certutil -addstore -f "ROOT" %TEMP%/root.crt
+```
+
+## Using Custom TLS Certificates
+
+By default, Caddy will automatically generate TLS certificates using Let's Encrypt or ZeroSSL.
+But sometimes you may prefer using custom certificates.
+
+For instance, to use self-signed certificates created with [mkcert](https://github.com/FiloSottile/mkcert) do as follows:
+
+1. Locally install `mkcert`
+2. Create the folder storing the certs: 
+   `mkdir docker/caddy/certs -p`
+3. Generate the certificates for your local host (example: "server-name.localhost"):
+   `mkcert -cert-file docker/caddy/certs/tls.pem -key-file docker/caddy/certs/tls.key "server-name.localhost"`
+4. Add these lines to the `./docker-compose.override.yml` file about `CADDY_EXTRA_CONFIG` environment and volume for the `caddy` service :
+    ```diff
+    caddy:
+    +  environment:
+    +    CADDY_EXTRA_CONFIG: "tls /etc/caddy/certs/tls.pem /etc/caddy/certs/tls.key"
+      volumes:
+    +    - ./docker/caddy/certs:/etc/caddy/certs:ro
+        - ./public:/srv/app/public:ro
+    ```
+5. Restart your `caddy` container