Support custom headers when fetching configuration through HTTP

docs/content/providers/http.md

@@ -76,6 +76,26 @@ providers:
 --providers.http.pollTimeout=5s
 ```
 
+### `headers`
+
+_Optional_
+
+Defines custom headers to be sent to the endpoint.
+
+```yaml tab="File (YAML)"
+providers:
+  headers:
+    name: value
+```
+
+```toml tab="File (TOML)"
+[providers.http.headers]
+  name = "value"
+```
+
+```bash tab="CLI"
+--providers.http.headers.name=value
+
 ### `tls`
 
 _Optional_

docs/content/reference/static-configuration/cli-ref.md

@@ -645,6 +645,9 @@ Enable HTTP backend with default settings. (Default: ```false```)
 `--providers.http.endpoint`:  
 Load configuration from this endpoint.
 
+`--providers.http.headers.<name>`:  
+Define custom headers to be sent to the endpoint.
+
 `--providers.http.pollinterval`:  
 Polling interval for endpoint. (Default: ```5```)
 

docs/content/reference/static-configuration/env-ref.md

@@ -645,6 +645,9 @@ Enable HTTP backend with default settings. (Default: ```false```)
 `TRAEFIK_PROVIDERS_HTTP_ENDPOINT`:  
 Load configuration from this endpoint.
 
+`TRAEFIK_PROVIDERS_HTTP_HEADERS_<NAME>`:  
+Define custom headers to be sent to the endpoint.
+
 `TRAEFIK_PROVIDERS_HTTP_POLLINTERVAL`:  
 Polling interval for endpoint. (Default: ```5```)
 

docs/content/reference/static-configuration/file.toml

@@ -252,6 +252,9 @@
     endpoint = "foobar"
     pollInterval = "42s"
     pollTimeout = "42s"
+    [providers.http.headers]
+      name0 = "foobar"
+      name1 = "foobar"
     [providers.http.tls]
       ca = "foobar"
       caOptional = true

docs/content/reference/static-configuration/file.yaml

@@ -280,6 +280,9 @@ providers:
     endpoint: foobar
     pollInterval: 42s
     pollTimeout: 42s
+    headers:
+      name0: foobar
+      name1: foobar
     tls:
       ca: foobar
       caOptional: true