feat: add helm log level / zap-devel config and configurable slog LOG_LEVEL

Author: umswmayj

cmd/main.go

@@ -12,6 +12,7 @@ import (
 	"os"
 	"path/filepath"
 	"slices"
+	"strings"
 	"time"
 
 	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
@@ -151,10 +152,27 @@ func main() {
 
 	ctrl.SetLogger(zap.New(zap.UseFlagOptions(&opts)))
 
-	// Configure slog (used across internal packages) with structured JSON output.
+	// Configure slog (used across internal packages) with JSON output and
+	// level control via the LOG_LEVEL environment variable.
+	// Supported values: debug, info (default), warn, error.
+	slogLevel := new(slog.LevelVar)
+	slogLevel.Set(slog.LevelInfo)
+	if lvl := os.Getenv("LOG_LEVEL"); lvl != "" {
+		switch strings.ToLower(lvl) {
+		case "debug":
+			slogLevel.Set(slog.LevelDebug)
+		case "info":
+			slogLevel.Set(slog.LevelInfo)
+		case "warn", "warning":
+			slogLevel.Set(slog.LevelWarn)
+		case "error":
+			slogLevel.Set(slog.LevelError)
+		}
+	}
 	slog.SetDefault(slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
-		Level: slog.LevelInfo,
+		Level: slogLevel,
 	})))
+	slog.Info("slog configured", "level", slogLevel.Level().String())
 
 	// Log the main configuration
 	setupLog.Info("loaded main configuration",

cortex.secrets.example.yaml

@@ -1,8 +1,9 @@
 # Copyright SAP SE
 # SPDX-License-Identifier: Apache-2.0
 
-# Override config values that contain sensitive information or
-# are specific to your environment. These values can be used in the Tiltfile.
+# Override config values for local development. This includes secrets,
+# environment-specific settings, and logging configuration.
+# These values can be used in the Tiltfile.
 
 # SSO certificate to use.
 sharedSSOCert: &sharedSSOCert
@@ -20,6 +21,23 @@ sharedSSOCert: &sharedSSOCert
   # If true, the certificate is not verified.
   selfSigned: "false"
 
+# Logging configuration for local development.
+# Set logLevel to "debug" for verbose output from both zap and slog loggers.
+# Set zapDevel to true for human-readable console logs instead of JSON.
+# These apply per sub-chart, e.g. for cortex-nova:
+#
+# cortex-scheduling-controllers:
+#   controllerManager:
+#     container:
+#       logLevel: "debug"
+#       zapDevel: true
+#
+# cortex-knowledge-controllers:
+#   controllerManager:
+#     container:
+#       logLevel: "debug"
+#       zapDevel: true
+
 # Enable kvm pipelines and scheduling support.
 kvm:
   enabled: true

helm/library/cortex/templates/_helpers.tpl

@@ -41,6 +41,22 @@ app.kubernetes.io/instance: {{ .Release.Name }}
 {{ $hasMutating }}}}{{- end }}
 
 
+{{/*
+chart.argsContainPrefix checks if any string in args starts with prefix.
+Usage: include "chart.argsContainPrefix" (dict "prefix" "--zap-log-level" "args" .Values.controllerManager.container.args)
+Returns "true" or "false".
+*/}}
+{{- define "chart.argsContainPrefix" -}}
+{{- $prefix := .prefix -}}
+{{- $result := dict "found" "false" -}}
+{{- range .args -}}
+  {{- if hasPrefix $prefix . -}}
+    {{- $_ := set $result "found" "true" -}}
+  {{- end -}}
+{{- end -}}
+{{- get $result "found" -}}
+{{- end -}}
+
 {{- define "chart.hasValidatingWebhooks" -}}
 {{- $hasValidating := false }}
 {{- range . }}

helm/library/cortex/templates/manager/manager.yaml

@@ -35,6 +35,12 @@ spec:
             {{- range .Values.controllerManager.container.args }}
             - {{ . }}
             {{- end }}
+            {{- if and .Values.controllerManager.container.logLevel (ne (include "chart.argsContainPrefix" (dict "prefix" "--zap-log-level" "args" .Values.controllerManager.container.args)) "true") }}
+            - "--zap-log-level={{ .Values.controllerManager.container.logLevel }}"
+            {{- end }}
+            {{- if and .Values.controllerManager.container.zapDevel (ne (include "chart.argsContainPrefix" (dict "prefix" "--zap-devel" "args" .Values.controllerManager.container.args)) "true") }}
+            - "--zap-devel"
+            {{- end }}
             {{- if and .Values.webhook.enable .Values.certmanager.enable }}
             - "--webhook-cert-path=/tmp/k8s-webhook-server/serving-certs"
             {{- end }}
@@ -56,13 +62,17 @@ spec:
           {{- if .Values.controllerManager.container.image.pullPolicy }}
           imagePullPolicy: {{ .Values.controllerManager.container.image.pullPolicy }}
           {{- end }}
-          {{- if .Values.controllerManager.container.env }}
           env:
+            {{- if and .Values.controllerManager.container.logLevel (not (and .Values.controllerManager.container.env (hasKey .Values.controllerManager.container.env "LOG_LEVEL"))) }}
+            - name: LOG_LEVEL
+              value: {{ .Values.controllerManager.container.logLevel | quote }}
+            {{- end }}
+            {{- if .Values.controllerManager.container.env }}
             {{- range $key, $value := .Values.controllerManager.container.env }}
             - name: {{ $key }}
               value: {{ $value }}
             {{- end }}
-          {{- end }}
+            {{- end }}
           livenessProbe:
             {{- toYaml .Values.controllerManager.container.livenessProbe | nindent 12 }}
           readinessProbe:
@@ -140,4 +150,4 @@ data:
     {{- $mergedSecrets = mergeOverwrite .Values.secrets $mergedSecrets }}
     {{- end }}
     {{ toJson $mergedSecrets | b64enc }}
-{{- end }}
+{{- end }}

helm/library/cortex/values.yaml

@@ -13,6 +13,14 @@ controllerManager:
       - "--metrics-bind-address=:2112"
       - "--health-probe-bind-address=:8081"
       - "--metrics-secure=false"
+    # Log level for both zap (controller-runtime) and slog (internal packages).
+    # Supported: debug, info (default), warn, error.
+    logLevel: "info"
+    # Enable zap development mode (human-readable console logs, development stack traces).
+    # This only changes output format and stack trace behavior, not the log level.
+    # The effective log level is controlled by logLevel above (default: "info").
+    # Set to true for local development (e.g. Tilt), keep false for production.
+    zapDevel: false
     resources:
       limits:
         cpu: 500m