bug: Langfuse Helm Chart Deploys Resources in Default Namespace When Installed via Terraform helm_release

[devopstechpro]

Describe the bug

📋 Summary

When installing the Langfuse Helm chart using Terraform's helm_release resource, the web and worker deployments (and other resources) are deployed in the default namespace instead of the specified release namespace, despite setting the namespace parameter in the helm_release resource.

🏷️ Issue Type

• Type: Bug
• Severity: High
• Component: Helm Chart Templates
• Affects: Terraform helm_release users

🔧 Environment

• Chart Version: 1.5.8
• Terraform Version: 1.13.4
• Helm Provider Version: 3.0.0-pre2
• Kubernetes Version: 1.13.1

📝 Description

The Langfuse Helm chart templates are missing explicit namespace fields in their metadata sections. This causes resources to be deployed in the default namespace when using Terraform's helm_release resource, regardless of the namespace parameter specified in the Terraform configuration.

🔍 Root Cause Analysis

The issue occurs because:

1. Terraform helm_release behavior: The namespace parameter in helm_release only affects resources that explicitly reference {{ .Release.Namespace }} in their templates
2. Missing namespace in templates: The Langfuse chart templates don't include namespace: {{ .Release.Namespace }} in their metadata
3. Kubectl context fallback: When templates lack explicit namespace, Kubernetes deploys resources in the current kubectl context namespace (typically default)

📁 Affected Files

The following templates are missing namespace: {{ .Release.Namespace }} in their metadata:

File	Resource Type	Status
templates/web/deployment.yaml	Web Deployment	❌ Missing namespace
templates/worker/deployment.yaml	Worker Deployment	❌ Missing namespace
templates/web/service.yaml	Web Service	❌ Missing namespace
templates/serviceaccount.yaml	ServiceAccount	❌ Missing namespace
templates/ingress.yaml	Ingress	❌ Missing namespace

🔧 Current Template Structure (Problematic)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "langfuse.fullname" . }}-web
  labels:
    # ... labels

✅ Proposed Fix

Add namespace: {{ .Release.Namespace }} to the metadata section of all affected templates:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "langfuse.fullname" . }}-web
  namespace: {{ .Release.Namespace }}
  labels:
    # ... labels

🎯 Impact Assessment

High Impact Areas:

• Infrastructure as Code: Breaks namespace-based infrastructure management
• CI/CD Pipelines: Causes deployment failures in namespace-restricted environments
• Multi-environment deployments: Resources end up in wrong namespaces
• Resource management: Terraform state becomes inconsistent with actual resource locations

Affected Users:

• Terraform users deploying Langfuse via helm_release
• CI/CD pipelines using Terraform for infrastructure management
• Multi-tenant environments with namespace isolation requirements

🔄 Workaround

Users must manually modify the chart templates or use kubectl context switching, which defeats the purpose of using Terraform for infrastructure management.

📊 Additional Context

• This issue is specific to Terraform helm_release usage
• When installing the chart directly with helm install, the behavior may differ depending on the kubectl context
• The sub-charts (postgresql, clickhouse, redis, s3) correctly support namespaceOverride configuration
• The main chart templates lack explicit namespace handling

---

To reproduce

🚀 Steps to Reproduce

1. Create a Terraform configuration:

resource "helm_release" "langfuse" {
  name      = "langfuse"
  namespace = "langfuse"
  repository = "https://langfuse.github.io/langfuse-k8s"
  chart     = "langfuse"
  version   = "1.5.8"
}

2. Apply the configuration:

terraform apply

3. Check pod locations:

kubectl get pods --all-namespaces | grep langfuse

✅ Expected Behavior

All Langfuse resources should be deployed in the langfuse namespace as specified in the helm_release resource.

❌ Actual Behavior

Web and worker pods are deployed in the default namespace, while the helm_release resource shows as deployed in the langfuse namespace.

Chart version and values.yaml configuration

Terraform resource snippet

resource "helm_release" "langfuse" {
  name             = "langfuse"
  namespace        = kubernetes_namespace.langfuse.metadata[0].name
  create_namespace = false
  description      = "Langfuse LLM Observability Platform"

  repository = "https://langfuse.github.io/langfuse-k8s"
  chart      = "langfuse"
  version    = "1.5.8"
  timeout    = 600 # 10 minutes timeout

  depends_on = [
    kubernetes_namespace.neuraverse,
    kubernetes_secret.langfuse_postgres_secret,
    kubernetes_secret.langfuse_s3_secret
  ]
  values = [
    yamlencode({
      # Global configuration
      global = {
        security = {
          allowInsecureImages = true
        }
      }
      # Langfuse core configuration
      langfuse = {
        salt = {
          secretKeyRef = {
            name = "langfuse-configs"
            key  = "SALT_KEY"
          }
        }
        nextauth = {
          secret = {
            secretKeyRef = {
              name = "langfuse-configs"
              key  = "NEXT_AUTH_SECRET"
            }
          }
        }
      }

      # Redis configuration
      redis = {
        auth = {
          password = "langfuse-redis-secret"
        }
      }

      # ClickHouse configuration
      clickhouse = {
        auth = {
          password = "langfuse-clickhouse-secret"
        }
      }
    })
  ]
}

Kubernetes Status

No response

Logs

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Additional information

No response

Are you interested to contribute a fix for this bug?

Yes

[devopstechpro]

The same issue was reported here already #138

[Steffen911]

Fixed via #138