Add like FileBeat topic: '%{[kubernetes.node.labels.kubcluster_name]}-%{[kubernetes.namespace]}'

[mgfnv9]

When trying to configure dynamic Kafka topics based on Kubernetes metadata (kubernetes_logs source) while deploying Vector via the official Helm chart, there is a syntax collision between Helm (Go templates) and Vector's native templating syntax ({{ ... }}).To ReproduceConfiguring the topic field inside values.yaml under customConfig like this:yamltopic: '{{ kubernetes.node.labels.kubcluster_name }}-{{ kubernetes.namespace }}'
Используйте код с осторожностью.Causes Helm to fail during helm template or execution phase with the following error:texterror calling tpl: cannot parse template ... template: gotpl:18: function "kubernetes" not defined
How to define kafka topic like this '%{[kubernetes.node.labels.kubcluster_name]}-%{[kubernetes.namespace]}'

[agrovr]

There are two separate issues here:

1. The official chart renders customConfig through Helm's tpl, so Helm tries to evaluate Vector's {{ ... }} expression first.
2. Filebeat's Kubernetes paths are not Vector's default paths. With the default legacy namespace, Vector uses .kubernetes.node_labels and .kubernetes.pod_namespace.

Escape the complete Vector expression through Helm's print function, while leaving the inner braces for Vector:

customConfig:
  sinks:
    kafka:
      # ...the rest of the Kafka sink config...
      topic: |-
        {{ print "{{ .kubernetes.node_labels.kubcluster_name }}-{{ .kubernetes.pod_namespace }}" }}

Then render the chart before deploying:

helm template my-vector vector/vector -f values.yaml > rendered.yaml

The generated ConfigMap should still contain the Vector template, not a Helm expression:

topic: |-
  {{ .kubernetes.node_labels.kubcluster_name }}-{{ .kubernetes.pod_namespace }}

The leading dots are intentional: the contents of a Vector template are VRL path expressions. If the Kubernetes label itself contains dots or /, quote that key. For example, inside the Helm print string the Vector path would look like:

{{ print "{{ .kubernetes.node_labels.\"label.example.com/name\" }}-{{ .kubernetes.pod_namespace }}" }}

This assumes the kubernetes_logs source's default legacy field layout. If you changed its annotation field paths or enabled a different log namespace, inspect one enriched event and use the resulting path instead.

One last operational detail: when a field used by a topic template is absent, Vector logs a template error and drops that event (component_errors_total with error_type="template_failed"). It is worth checking that every node has kubcluster_name, or normalizing/filling the field in a remap transform before the Kafka sink.

References: chart escaping example · Vector template syntax · kubernetes_logs output fields

[mgfnv9]

Thank you!