fix: Disable create-reporting-task for NiFi 2.x and document regression

CHANGELOG.md

@@ -21,6 +21,7 @@ All notable changes to this project will be documented in this file.
   - `extraVolumes`
 - Increase `log` Volume size from 33 MiB to 500 MiB ([#671]).
 - Replaced experimental NiFi `2.0.0-M4` with `2.0.0` ([#702]).
+- Remove the automatic deployment of the PrometheusReportingTask for NiFi versions `2.x.x` and up ([#708]).
 
 ### Fixed
 
@@ -46,6 +47,7 @@ All notable changes to this project will be documented in this file.
 [#694]: https://github.com/stackabletech/nifi-operator/pull/694
 [#698]: https://github.com/stackabletech/nifi-operator/pull/698
 [#702]: https://github.com/stackabletech/nifi-operator/pull/702
+[#708]: https://github.com/stackabletech/nifi-operator/pull/708
 
 ## [24.7.0] - 2024-07-24
 

docs/modules/nifi/pages/usage_guide/monitoring.adoc

@@ -3,8 +3,14 @@
 :k8s-job: https://kubernetes.io/docs/concepts/workloads/controllers/job/
 :k8s-network-policies: https://kubernetes.io/docs/concepts/services-networking/network-policies/
 
-The operator automatically configures NiFi to export Prometheus metrics.
-This is done by creating a {k8s-job}[Job] that connects to NiFi and configures a reporting task.
+In November 2024, Apache NiFi released a new major version https://cwiki.apache.org/confluence/display/NIFI/Release+Notes#ReleaseNotes-Version2.0.0[`2.0.0`].
+
+The NiFi `2.0.0` release changed the way of exposing Prometheus metrics significantly. The following steps explain on how to expose Metrics in NiFi versions `1.x.x` and `2.x.x`.
+
+== Configure metrics in NiFi `1.x.x`
+
+For NiFi versions `1.x.x`, the operator automatically configures NiFi to export Prometheus metrics.
+This is done by creating a {k8s-job}[Job] that connects to NiFi and configures a https://nifi.apache.org/docs/nifi-docs/components/org.apache.nifi/nifi-prometheus-nar/1.26.0/org.apache.nifi.reporting.prometheus.PrometheusReportingTask/index.html[Prometheus Reporting Task].
 
 IMPORTANT: Network access from the Job to NiFi is required.
 If you are running a Kubernetes with restrictive {k8s-network-policies}[NetworkPolicies], make sure to allow access from the Job to NiFi.
@@ -24,3 +30,15 @@ spec:
     createReportingTaskJob:
       enabled: false
 ----
+
+== Configure metrics in NiFi `2.x.x`
+
+The Prometheus Reporting Task was removed in NiFi `2.x.x`. Metrics are now exposed automatically and can be scraped using the NiFi pod FQDN and the route `/nifi-api/flow/metrics/prometheus`.
+
+For a deployed single node NiFi cluster called `simple-nifi`, containing a rolegroup called `default`, the metrics endpoint is reachable under:
+
+```
+https://simple-nifi-node-default-0.simple-nifi-node-default.<namespace>.svc.cluster.local:8443/nifi-api/flow/metrics/prometheus
+```
+
+IMPORTANT: If NiFi is configured to use any Authentication, requests to the metric endpoint must be authenticated and authorized.

rust/operator-binary/src/controller.rs

@@ -85,7 +85,7 @@ use crate::{
     },
     operations::{graceful_shutdown::add_graceful_shutdown_config, pdb::add_pdbs},
     product_logging::{extend_role_group_config_map, resolve_vector_aggregator_address},
-    reporting_task::{self, build_reporting_task, build_reporting_task_service_name},
+    reporting_task::{self, build_maybe_reporting_task, build_reporting_task_service_name},
     security::{
         authentication::{
             NifiAuthenticationConfig, AUTHORIZERS_XML_FILE_NAME,
@@ -616,24 +616,25 @@ pub async fn reconcile_nifi(
 
     // Only add the reporting task in case it is enabled.
     if nifi.spec.cluster_config.create_reporting_task_job.enabled {
-        let (reporting_task_job, reporting_task_service) = build_reporting_task(
+        if let Some((reporting_task_job, reporting_task_service)) = build_maybe_reporting_task(
             nifi,
             &resolved_product_image,
             &client.kubernetes_cluster_info,
             &nifi_authentication_config,
             &rbac_sa.name_any(),
         )
-        .context(ReportingTaskSnafu)?;
-
-        cluster_resources
-            .add(client, reporting_task_service)
-            .await
-            .context(ApplyCreateReportingTaskServiceSnafu)?;
+        .context(ReportingTaskSnafu)?
+        {
+            cluster_resources
+                .add(client, reporting_task_service)
+                .await
+                .context(ApplyCreateReportingTaskServiceSnafu)?;
 
-        cluster_resources
-            .add(client, reporting_task_job)
-            .await
-            .context(ApplyCreateReportingTaskJobSnafu)?;
+            cluster_resources
+                .add(client, reporting_task_job)
+                .await
+                .context(ApplyCreateReportingTaskJobSnafu)?;
+        }
     }
 
     // Remove any orphaned resources that still exist in k8s, but have not been added to

rust/operator-binary/src/reporting_task/mod.rs

@@ -112,7 +112,8 @@ pub enum Error {
 
 type Result<T, E = Error> = std::result::Result<T, E>;
 
-/// Build required resources to create the reporting task in NiFi.
+/// Build required resources to create the reporting task in NiFi versions 1.x.
+///
 /// This will return
 /// * a Job that creates and runs the reporting task via the NiFi Rest API.
 /// * a Service that contains of one single NiFi node.
@@ -122,23 +123,30 @@ type Result<T, E = Error> = std::result::Result<T, E>;
 /// from SingleUserLoginIdentityProvider to the FQDN of the pod.
 /// The NiFi role service will randomly delegate to different NiFi nodes which will
 /// then fail requests to other nodes.
-pub fn build_reporting_task(
+///
+/// NiFi 2.x and above automatically server Prometheus metrics via the API, but as of 2024-11-08
+/// requires authentication.
+pub fn build_maybe_reporting_task(
     nifi: &NifiCluster,
     resolved_product_image: &ResolvedProductImage,
     cluster_info: &KubernetesClusterInfo,
     nifi_auth_config: &NifiAuthenticationConfig,
     sa_name: &str,
-) -> Result<(Job, Service)> {
-    Ok((
-        build_reporting_task_job(
-            nifi,
-            resolved_product_image,
-            cluster_info,
-            nifi_auth_config,
-            sa_name,
-        )?,
-        build_reporting_task_service(nifi, resolved_product_image)?,
-    ))
+) -> Result<Option<(Job, Service)>> {
+    if resolved_product_image.product_version.starts_with("1.") {
+        Ok(Some((
+            build_reporting_task_job(
+                nifi,
+                resolved_product_image,
+                cluster_info,
+                nifi_auth_config,
+                sa_name,
+            )?,
+            build_reporting_task_service(nifi, resolved_product_image)?,
+        )))
+    } else {
+        Ok(None)
+    }
 }
 
 /// Return the name of the reporting task.

tests/templates/kuttl/smoke/60-assert.yaml → tests/templates/kuttl/smoke/60-assert.yaml.j2

@@ -4,4 +4,6 @@ kind: TestAssert
 timeout: 300
 commands:
   - script: kubectl exec -n $NAMESPACE test-nifi-0 -- python /tmp/test_nifi.py -u admin -p 'passwordWithSpecialCharacter\@<&>"'"'" -n $NAMESPACE -c 3
+{% if test_scenario['values']['nifi'].startswith('1.') %}
   - script: kubectl exec -n $NAMESPACE test-nifi-0 -- python /tmp/test_nifi_metrics.py -n $NAMESPACE
+{% endif %}