Add support for multiple docker hosts

README.md

@@ -1,10 +1,10 @@
 # Auto-proxy - Docker mod for SWAG
 
-This mod gives SWAG the ability to auto-detect running containers via labels and automatically enable reverse proxy for them.
+This mod gives SWAG the ability to auto-detect running containers, across multiple hosts, via labels and automatically enable reverse proxy for them.
 
 ## Requirements:
 - This mod needs the [universal-docker mod](https://github.com/linuxserver/docker-mods/tree/universal-docker) installed and set up with either mapping `docker.sock` or setting the environment variable `DOCKER_HOST=remoteaddress`.
-- Other containers to be auto-detected and reverse proxied should be in the same [user defined bridge network](https://docs.linuxserver.io/general/swag#docker-networking) as SWAG.
+- Other containers detected via `docker.sock` to be auto-detected and reverse proxied should be in the same [user defined bridge network](https://docs.linuxserver.io/general/swag#docker-networking) as SWAG.
 - Containers to be auto-detected and reverse proxied must have a label `swag=enable` at a minimum.
 - To benefit from curated preset proxy confs we provide, the container name must match the container names that are suggested in our readme examples (ie. `radarr` and not `Radarr-4K`).
 
@@ -36,3 +36,63 @@ Here's a sample compose yaml snippet for tecnativa/docker-socket-proxy:
       - POST=0
 ```
 Then the env var in SWAG can be set as `DOCKER_HOST=dockerproxy`. This will allow docker cli in SWAG to be able to retrieve info on other containers, but it won't be allowed to spin up new containers.
+
+## Multiple Hosts:
+
+If both `DOCKER_HOST` and `docker.sock` volumes are provided this mod will detect containers using both connections. As noted in the [requirements](#requirements), containers detected via `docker.sock` must be in the same user defined network or have `swag_address` label set.
+
+Multiple remote hosts can be used via `DOCKER_HOST` by separating hosts with a comma. Additional per-host settings can be assigned by separating with a pipe `|`. The syntax for per-host configuration:
+
+```
+host:port|friendly_name|default_tld
+```
+
+
+```
+DOCKER_HOST=192.168.0.100:2375|serverA,192.168.0.110:2375|serverB|local.test,192.168.0.130:2375
+```
+
+* Host: `192.168.0.100:2375` -- Friendly Name: `serverA` -- TLD: `*`
+* Host: `192.168.0.110:2375` -- Friendly Name: `serverB` -- TLD: `local.test`
+* Host: `192.168.0.130:2375` -- Friendly Name: `host3` -- TLD: `*`
+
+### Upstream IP and Port
+
+When using a remote docker host from `DOCKER_HOST` auto-proxy assumes the detected containers are not on the same network as SWAG:
+
+* If the detected containers do not have the `swag_address` label set then the Host IP will be used.
+* If the detected containers do not have the `swag_port` label set then auto-proxy looks for exposed **container ports** and uses the corresponding **host port** as the upstream port. Container ports are checked in this order:
+  * 80
+  * 8080
+  * The first mapped port, if any
+
+### Subdomains and TLD
+
+If a detected container does not have the `swag_url` label set then the subdomain and TLD can be programmatically generated.
+
+The default TLD used in nginx [`server_name` directive](https://nginx.org/en/docs/http/server_names.html) can be set using `AUTO_PROXY_HOST_TLD`. This can also be set per-host using the syntax described in [`DOCKER_HOST` for `default_tld`.](#multiple-hosts)
+
+The subdomain used for a container can optionally be modified to include the Host's `friendly_name` described in the `DOCKER_HOST` syntax by setting `AUTO_PROXY_HOST_INSERT` to either `prefix` or `suffix`
+
+Examples using a container named `overseer`:
+
+* Using only AUTO_PROXY_HOST_INSERT to modify subdomain
+  * `DOCKER_HOST=192.168.0.100:2375|serverA`
+  * `AUTO_PROXY_HOST_TLD` (not set, defaults to `*`)
+  * `AUTO_PROXY_HOST_INSERT`
+    * (unset) => nginx `server_name overseer.*`
+    * `prefix` => nginx `server_name serverA-overseer.*`
+    * `suffix` => nginx `server_name overseer-serverA.*`
+* Using AUTO_PROXY_HOST_INSERT prefix and AUTO_PROXY_HOST_TLD
+  * `DOCKER_HOST=192.168.0.100:2375|serverA`
+  * `AUTO_PROXY_HOST_TLD=test.home`
+  * `AUTO_PROXY_HOST_INSERT=prefix`
+    * `server_name serverA-overseer.test.home`
+* Using AUTO_PROXY_HOST_INSERT prefix and default_tld
+  * `DOCKER_HOST=192.168.0.100:2375|serverA|myserver.home`
+  * `AUTO_PROXY_HOST_INSERT=prefix`
+    * `server_name serverA-overseer.myserver.home`
+* Using AUTO_PROXY_HOST_TLD only
+  * `DOCKER_HOST=192.168.0.100:2375`
+  * `AUTO_PROXY_HOST_TLD=myserver.home`
+    * `server_name overseer.myserver.home`