Support for watching instead of polling Nomad

docs/content/providers/nomad.md

@@ -56,6 +56,8 @@ _Optional, Default=15s_
 
 Defines the polling interval.
 
+!!! note "This option is ignored when the [watch](#watch) mode is enabled."
+
 ```yaml tab="File (YAML)"
 providers:
   nomad:
@@ -74,6 +76,62 @@ providers:
 # ...
 ```
 
+### `watch`
+
+_Optional, Default=false_
+
+Enables the watch mode to refresh the configuration on a per-event basis.
+
+```yaml tab="File (YAML)"
+providers:
+  nomad:
+    watch: true
+    # ...
+```
+
+```toml tab="File (TOML)"
+[providers.nomad]
+  watch = true
+  # ...
+```
+
+```bash tab="CLI"
+--providers.nomad.watch
+# ...
+```
+
+### `throttleDuration`
+
+_Optional, Default=0s_
+
+The `throttleDuration` option defines how often the provider is allowed to handle service events from Nomad.
+This prevents a Nomad cluster that updates many times per second from continuously changing your Traefik configuration.
+
+If left empty, the provider does not apply any throttling and does not drop any Nomad service events.
+
+The value of `throttleDuration` should be provided in seconds or as a valid duration format,
+see [time.ParseDuration](https://golang.org/pkg/time/#ParseDuration).
+
+!!! warning "This option is only compatible with the [watch](#watch) mode."
+
+```yaml tab="File (YAML)"
+providers:
+  nomad:
+    throttleDuration: 2s
+    # ...
+```
+
+```toml tab="File (TOML)"
+[providers.nomad]
+  throttleDuration = "2s"
+  # ...
+```
+
+```bash tab="CLI"
+--providers.nomad.throttleDuration=2s
+# ...
+```
+
 ### `prefix`
 
 _required, Default="traefik"_

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

@@ -918,6 +918,12 @@ Interval for polling Nomad API. (Default: ```15```)
 `--providers.nomad.stale`:  
 Use stale consistency for catalog reads. (Default: ```false```)
 
+`--providers.nomad.throttleduration`:  
+Watch throttle duration. (Default: ```0```)
+
+`--providers.nomad.watch`:  
+Watch Nomad Service events. (Default: ```false```)
+
 `--providers.plugin.<name>`:  
 Plugins configuration.
 

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

@@ -918,6 +918,12 @@ Interval for polling Nomad API. (Default: ```15```)
 `TRAEFIK_PROVIDERS_NOMAD_STALE`:  
 Use stale consistency for catalog reads. (Default: ```false```)
 
+`TRAEFIK_PROVIDERS_NOMAD_THROTTLEDURATION`:  
+Watch throttle duration. (Default: ```0```)
+
+`TRAEFIK_PROVIDERS_NOMAD_WATCH`:  
+Watch Nomad Service events. (Default: ```false```)
+
 `TRAEFIK_PROVIDERS_PLUGIN_<NAME>`:  
 Plugins configuration.
 

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

@@ -203,6 +203,8 @@
     exposedByDefault = true
     refreshInterval = "42s"
     allowEmptyServices = true
+    watch = true
+    throttleDuration = "42s"
     namespaces = ["foobar", "foobar"]
     [providers.nomad.endpoint]
       address = "foobar"

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

@@ -236,6 +236,8 @@ providers:
     exposedByDefault: true
     refreshInterval: 42s
     allowEmptyServices: true
+    watch: true
+    throttleDuration: 42s
     namespaces:
       - foobar
       - foobar