feat(helm): add billingMetrics values to the classic chart

The componentized chart just gained a first-class billingMetrics block; this
mirrors it in litellm-helm so enabling enterprise billable-request metering no
longer means hand-rolling the env vars and the cert volume through envVars and
volumes.

When enabled the proxy Deployment renders LITELLM_BILLING_METRICS_ENDPOINT plus
the two cert paths, and mounts secretName read-only at /etc/litellm/billing-mtls.
secretName defaults to litellm-billing-metrics-mtls, the conventional name, so
enabling the block is enough once that Secret exists. caSecretName is optional
and only needed for private collectors whose server certificate is not on the
public web PKI; when set it mounts at /etc/litellm/billing-mtls-ca and adds the
CA env var. exportIntervalMs is passed through only when set.

The env entries render after envVars and extraEnvVars, so a user-supplied
LITELLM_BILLING_METRICS_ENDPOINT cannot silently redirect the export under
Kubernetes last-wins duplicate-env semantics; this is the same ordering the
migrations Job relies on for DISABLE_SCHEMA_UPDATE.

Enabling with an emptied secretName or endpoint fails the render with a named
message rather than producing a proxy that silently never exports.

The generic volumes, volumeMounts, envVars and extraEnvVars paths are untouched
and still compose with this, so existing overlays keep working. The chart has no
values.schema.json; README parameters and a setup section are updated.

  helm unittest -f 'tests/*.yaml' helm/litellm-helm  # 68 passed (54 + 14 new)
  helm lint helm/litellm-helm                        # 0 failed

helm/litellm-helm/README.md

@@ -54,6 +54,12 @@ If `db.useStackgresOperator` is used (not yet implemented):
 | `pdb.annotations`           | Extra metadata annotations to add to the PDB                                                                                                                                                                                                  | `{}`                      |
 | `pdb.labels`                | Extra metadata labels to add to the PDB                                                                                                                                                                                                       | `{}`                      |
 
+| `billingMetrics.enabled`    | Enable enterprise billable-request metering. Requires an enterprise license.                                                                                                                                                                  | `false`                   |
+| `billingMetrics.endpoint`   | Collector that the billable-request counter is pushed to.                                                                                                                                                                                    | `https://telemetry.litellm.ai` |
+| `billingMetrics.secretName` | Name of an existing Secret holding the mTLS client certificate, under the keys `tls.crt` and `tls.key`.                                                                                                                                       | `litellm-billing-metrics-mtls` |
+| `billingMetrics.caSecretName` | Name of an existing Secret holding a CA bundle under the key `ca.crt`. Only needed for a private or test collector whose server certificate is not on the public web PKI.                                                                    | `""`                      |
+| `billingMetrics.exportIntervalMs` | How often the counter is pushed, in milliseconds. The proxy defaults to `60000` when unset.                                                                                                                                             | `""`                      |
+
 #### Example `proxy_config` ConfigMap from values (default):
 
 ```
@@ -94,6 +100,21 @@ data:
 type: Opaque
 ```
 
+#### Enterprise billable-request metering
+
+Enterprise licenses meter billable requests by pushing a counter to LiteLLM's collector over mutual TLS. The chart does not create the client certificate; it mounts one you already hold, read-only, so the private key is never exposed through the environment. Create the Secret under the name the chart expects, then turn the block on:
+
+```
+kubectl create secret tls litellm-billing-metrics-mtls --cert=client.crt --key=client.key
+```
+
+```
+billingMetrics:
+  enabled: true
+```
+
+Set `billingMetrics.caSecretName` only when the collector is a private or test one whose server certificate is not on the public web PKI; the production collector needs no CA override. The chart fails the render rather than deploying a proxy that silently never exports, so a missing `secretName` or an emptied `endpoint` surfaces at `helm install` time.
+
 ### Database Settings
 
 | Name                      | Description                                                                                                                                                                                                                                                                               | Value                                                                                      |

helm/litellm-helm/templates/_helpers.tpl

@@ -50,6 +50,53 @@ app.kubernetes.io/name: {{ include "litellm.name" . }}
 app.kubernetes.io/instance: {{ .Release.Name }}
 {{- end }}
 
+{{/*
+Enterprise billable-request metering. The client certificate identifies the
+deployment to LiteLLM's collector, so it is mounted read-only from an existing
+Secret rather than passed through the environment.
+*/}}
+{{- define "litellm.billingMetrics.certDir" -}}/etc/litellm/billing-mtls{{- end -}}
+{{- define "litellm.billingMetrics.caDir" -}}/etc/litellm/billing-mtls-ca{{- end -}}
+
+{{- define "litellm.billingMetricsEnv" -}}
+- name: LITELLM_BILLING_METRICS_ENDPOINT
+  value: {{ required "billingMetrics.endpoint is required when billingMetrics.enabled is true" .Values.billingMetrics.endpoint | quote }}
+- name: LITELLM_BILLING_METRICS_CLIENT_CERT
+  value: {{ printf "%s/tls.crt" (include "litellm.billingMetrics.certDir" .) | quote }}
+- name: LITELLM_BILLING_METRICS_CLIENT_KEY
+  value: {{ printf "%s/tls.key" (include "litellm.billingMetrics.certDir" .) | quote }}
+{{- if .Values.billingMetrics.caSecretName }}
+- name: LITELLM_BILLING_METRICS_CA_CERT
+  value: {{ printf "%s/ca.crt" (include "litellm.billingMetrics.caDir" .) | quote }}
+{{- end }}
+{{- with .Values.billingMetrics.exportIntervalMs }}
+- name: LITELLM_BILLING_METRICS_EXPORT_INTERVAL_MS
+  value: {{ . | quote }}
+{{- end }}
+{{- end -}}
+
+{{- define "litellm.billingMetricsVolumes" -}}
+- name: billing-metrics-mtls
+  secret:
+    secretName: {{ required "billingMetrics.secretName is required when billingMetrics.enabled is true (an existing Secret with tls.crt and tls.key)" .Values.billingMetrics.secretName }}
+{{- if .Values.billingMetrics.caSecretName }}
+- name: billing-metrics-mtls-ca
+  secret:
+    secretName: {{ .Values.billingMetrics.caSecretName }}
+{{- end }}
+{{- end -}}
+
+{{- define "litellm.billingMetricsVolumeMounts" -}}
+- name: billing-metrics-mtls
+  mountPath: {{ include "litellm.billingMetrics.certDir" . }}
+  readOnly: true
+{{- if .Values.billingMetrics.caSecretName }}
+- name: billing-metrics-mtls-ca
+  mountPath: {{ include "litellm.billingMetrics.caDir" . }}
+  readOnly: true
+{{- end }}
+{{- end -}}
+
 {{/*
 Create the name of the service account to use
 */}}

helm/litellm-helm/templates/deployment.yaml

@@ -142,6 +142,9 @@ spec:
             {{- with .Values.extraEnvVars }}
               {{- toYaml . | nindent 12 }}
             {{- end }}
+            {{- if .Values.billingMetrics.enabled }}
+            {{- include "litellm.billingMetricsEnv" . | nindent 12 }}
+            {{- end }}
             {{- if .Values.migrationJob.enabled }}
             # Schema updates are owned by the dedicated migrations Job; skip
             # the proxy's startup `prisma db push` so N replicas don't race
@@ -220,6 +223,9 @@ spec:
             - name: npm
               mountPath: /.npm
           {{- end }}
+          {{- if .Values.billingMetrics.enabled }}
+            {{- include "litellm.billingMetricsVolumeMounts" . | nindent 12 }}
+          {{- end }}
           {{- with .Values.volumeMounts }}
             {{- toYaml . | nindent 12 }}
           {{- end }}
@@ -252,6 +258,9 @@ spec:
             items:
               - key: {{ .Values.proxyConfigMap.key | default "config.yaml" }}
                 path: "config.yaml"
+        {{- if .Values.billingMetrics.enabled }}
+        {{- include "litellm.billingMetricsVolumes" . | nindent 8 }}
+        {{- end }}
       {{- with .Values.volumes }}
         {{- toYaml . | nindent 8 }}
       {{- end }}

helm/litellm-helm/tests/billing_metrics_tests.yaml

@@ -0,0 +1,277 @@
+suite: test billingMetrics wiring on the proxy deployment
+templates:
+  - deployment.yaml
+  - configmap-litellm.yaml
+tests:
+  - it: is off by default, adding no env, volume, or mount
+    template: deployment.yaml
+    asserts:
+      - notContains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls
+            secret:
+              secretName: litellm-billing-metrics-mtls
+      - notContains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: billing-metrics-mtls
+            mountPath: /etc/litellm/billing-mtls
+            readOnly: true
+      - notContains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_ENDPOINT
+            value: https://telemetry.litellm.ai
+
+  - it: renders the endpoint and the mounted cert paths when enabled
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_ENDPOINT
+            value: https://telemetry.litellm.ai
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_CLIENT_CERT
+            value: /etc/litellm/billing-mtls/tls.crt
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_CLIENT_KEY
+            value: /etc/litellm/billing-mtls/tls.key
+
+  # The conventional Secret name is the default, so enabling the block is enough.
+  - it: mounts the default cert secret read-only alongside the config volume
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls
+            secret:
+              secretName: litellm-billing-metrics-mtls
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: billing-metrics-mtls
+            mountPath: /etc/litellm/billing-mtls
+            readOnly: true
+
+  - it: honours a secretName override
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        secretName: my-billing-mtls
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls
+            secret:
+              secretName: my-billing-mtls
+      - notContains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls
+            secret:
+              secretName: litellm-billing-metrics-mtls
+
+  - it: honours an endpoint override
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        endpoint: https://collector.internal:4318
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_ENDPOINT
+            value: https://collector.internal:4318
+
+  # The production collector presents a public web-PKI certificate, so the CA
+  # override must stay absent unless a private collector is configured.
+  - it: omits the CA env, volume, and mount when no caSecretName is set
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+    asserts:
+      - notContains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls-ca
+            secret:
+              secretName: billing-ca
+      - notContains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: billing-metrics-mtls-ca
+            mountPath: /etc/litellm/billing-mtls-ca
+            readOnly: true
+      - notContains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_CA_CERT
+            value: /etc/litellm/billing-mtls-ca/ca.crt
+
+  - it: mounts the CA secret when caSecretName is set
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        caSecretName: billing-ca
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_CA_CERT
+            value: /etc/litellm/billing-mtls-ca/ca.crt
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls-ca
+            secret:
+              secretName: billing-ca
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: billing-metrics-mtls-ca
+            mountPath: /etc/litellm/billing-mtls-ca
+            readOnly: true
+
+  - it: passes the export interval through only when set
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        exportIntervalMs: 5000
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_EXPORT_INTERVAL_MS
+            value: "5000"
+
+  - it: omits the export interval when unset
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+    asserts:
+      - notContains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_EXPORT_INTERVAL_MS
+            value: "60000"
+
+  # Kubernetes resolves duplicate env names last-wins, so the chart-owned billing
+  # entries must render after .Values.envVars or a user could silently redirect
+  # the metering export. The three billing entries are the last ones emitted here
+  # (migrationJob, which appends DISABLE_SCHEMA_UPDATE, is off for this case).
+  - it: renders the billing endpoint after envVars so it cannot be shadowed
+    template: deployment.yaml
+    set:
+      migrationJob:
+        enabled: false
+      billingMetrics:
+        enabled: true
+      envVars:
+        LITELLM_BILLING_METRICS_ENDPOINT: https://shadowed.example
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].env
+          content:
+            name: LITELLM_BILLING_METRICS_ENDPOINT
+            value: https://shadowed.example
+      - equal:
+          path: spec.template.spec.containers[0].env[-3]
+          value:
+            name: LITELLM_BILLING_METRICS_ENDPOINT
+            value: https://telemetry.litellm.ai
+      - equal:
+          path: spec.template.spec.containers[0].env[-2].name
+          value: LITELLM_BILLING_METRICS_CLIENT_CERT
+      - equal:
+          path: spec.template.spec.containers[0].env[-1].name
+          value: LITELLM_BILLING_METRICS_CLIENT_KEY
+
+  - it: keeps user-supplied volumes and mounts alongside the billing secret
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+      volumes:
+        - name: custom-callbacks
+          configMap:
+            name: my-callbacks
+      volumeMounts:
+        - name: custom-callbacks
+          mountPath: /app/callbacks
+    asserts:
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: custom-callbacks
+            configMap:
+              name: my-callbacks
+      - contains:
+          path: spec.template.spec.volumes
+          content:
+            name: billing-metrics-mtls
+            secret:
+              secretName: litellm-billing-metrics-mtls
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: custom-callbacks
+            mountPath: /app/callbacks
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: billing-metrics-mtls
+            mountPath: /etc/litellm/billing-mtls
+            readOnly: true
+
+  - it: still mounts the proxy config when enabled
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+    asserts:
+      - contains:
+          path: spec.template.spec.containers[0].volumeMounts
+          content:
+            name: litellm-config
+            mountPath: /etc/litellm/config.yaml
+            subPath: config.yaml
+
+  - it: fails loudly when enabled with an emptied secretName
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        secretName: ""
+    asserts:
+      - failedTemplate:
+          errorMessage: billingMetrics.secretName is required when billingMetrics.enabled is true (an existing Secret with tls.crt and tls.key)
+
+  - it: fails loudly when enabled without an endpoint
+    template: deployment.yaml
+    set:
+      billingMetrics:
+        enabled: true
+        endpoint: ""
+    asserts:
+      - failedTemplate:
+          errorMessage: billingMetrics.endpoint is required when billingMetrics.enabled is true

helm/litellm-helm/values.yaml

@@ -139,6 +139,20 @@ masterkeySecretName: ""
 # if set, use this secret key for the master key; otherwise, use the default key
 masterkeySecretKey: ""
 
+# Optional: enterprise billable-request metering. When enabled, the proxy counts
+# successful requests to inference, MCP, and A2A endpoints and pushes them to
+# LiteLLM's collector over mutual TLS. Requires an enterprise license.
+# The client certificate identifies the deployment, so it is mounted read-only
+# from an existing Secret and never passed through the environment.
+billingMetrics:
+  enabled: false
+  endpoint: https://telemetry.litellm.ai   # collector to push the counter to
+  secretName: litellm-billing-metrics-mtls # existing Secret holding tls.crt and tls.key
+  # Only for private or test collectors whose server certificate is not on the
+  # public web PKI. The production collector needs no CA override.
+  caSecretName: ""                         # existing Secret holding ca.crt
+  exportIntervalMs: ""                     # push cadence; the proxy defaults to 60000
+
 proxyConfigMap:
   # when true, creates a new configmap
   create: true