Base context path can be changed (#88)

Makefile

@@ -33,6 +33,8 @@ docker-run:
 
 docker-build-and-run: docker-build docker-run
 
+docker-run-proxied: frontend-build docker-build
+	docker compose -f ./compose-behind-proxy.yml up
 
 #############
 # Front end #

README.md

@@ -267,6 +267,7 @@ If you want to test it locally, see [Docker](#docker).
 | `ui.dashboard-subheading`    | Dashboard description between header and endpoints                                                                                       | `Monitor the health of your endpoints in real-time` |
 | `ui.header`                  | Header at the top of the dashboard.                                                                                                      | `Gatus`                    |
 | `ui.logo`                    | URL to the logo to display.                                                                                                              | `""`                       |
+| `ui.base`                    | `href` attribute of the HTML `<base>` tag. Use this if you want to host Gatus on a subpath (e.g. `/status/`). Has to end with '/'.       | `/`                        |
 | `ui.link`                    | Link to open when the logo is clicked.                                                                                                   | `""`                       |
 | `ui.buttons`                 | List of buttons to display below the header.                                                                                             | `[]`                       |
 | `ui.buttons[].name`          | Text to display on the button.                                                                                                           | Required `""`              |

compose-behind-proxy.yml

@@ -0,0 +1,46 @@
+networks:
+  caddy_network:
+    name: gatus_proxy_network
+
+services:
+  caddy:
+    networks:
+      - caddy_network
+    image: caddy:latest
+    container_name: gatus_proxy
+    ports:
+      - 8080:8080
+    configs:
+      - source: caddyfile
+        target: /etc/caddy/Caddyfile
+  gatus:
+    networks:
+      - caddy_network
+    image: twinproduction/gatus:latest
+    container_name: gatus_behind_proxy
+
+    volumes:
+      - ./config.yml:/config/02_config.yaml
+    environment:
+      - GATUS_CONFIG_PATH=/config
+    configs:
+      - source: gatus_config_ext
+        target: /config/01_config.yaml
+
+configs:
+  gatus_config_ext:
+    content: |
+      ui:
+        base: /gatus/
+  caddyfile:
+    content: |
+      {
+        auto_https off
+        http_port 8080
+      }
+
+      http://localhost:8080 {
+        handle_path /gatus* {
+            reverse_proxy http://gatus_behind_proxy:8080
+        }
+      }

config/ui/ui.go

@@ -20,6 +20,7 @@ const (
 	defaultCustomCSS            = ""
 	defaultSortBy               = "name"
 	defaultFilterBy             = "none"
+	defaultBase                 = "/"
 )
 
 var (
@@ -44,6 +45,7 @@ type Config struct {
 	DarkMode                *bool    `yaml:"dark-mode,omitempty"`              // DarkMode is a flag to enable dark mode by default
 	DefaultSortBy           string   `yaml:"default-sort-by,omitempty"`        // DefaultSortBy is the default sort option ('name', 'group', 'health')
 	DefaultFilterBy         string   `yaml:"default-filter-by,omitempty"`      // DefaultFilterBy is the default filter option ('none', 'failing', 'unstable')
+	Base                    string   `yaml:"base,omitempty"`        // href attribute for HTML base tag
 	//////////////////////////////////////////////
 	// Non-configurable - used for UI rendering //
 	//////////////////////////////////////////////
@@ -86,6 +88,7 @@ func GetDefaultConfig() *Config {
 		DefaultSortBy:          defaultSortBy,
 		DefaultFilterBy:        defaultFilterBy,
 		MaximumNumberOfResults: storage.DefaultMaximumNumberOfResults,
+		Base:                   defaultBase,
 	}
 }
 
@@ -115,6 +118,9 @@ func (cfg *Config) ValidateAndSetDefaults() error {
 	if len(cfg.CustomCSS) == 0 {
 		cfg.CustomCSS = defaultCustomCSS
 	}
+    if len(cfg.Base) == 0 {
+        cfg.Base = defaultBase
+    }
 	if cfg.DarkMode == nil {
 		cfg.DarkMode = &defaultDarkMode
 	}