This Helm chart simplifies deploying a typical "80% case" service on Kubernetes. It takes care of creating common Resources such as Deployment, Service and Ingress. It also provides optional support for:
- nginx Ingress Controller, Contour or Istio for routing
- Prometheus Operator for monitoring
- Loki Rule Operator or Loki sidecar for logging-based alerting
- OpenTelemetry Operator or Jaeger Operator for tracing
- Flagger and Argo Rollouts for canary and blue-green deployments
The Generic Service Grafana Dashboard is a useful companion to this chart.
This chart is most commonly used as a dependency instead of installing it directly. You can reference it in your chart by adding this to your Chart.yaml:
dependencies:
- name: generic-service
version: ~1.10.0
repository: https://helm.nano-byte.net
alias: appYou can then add static configuration to your values.yaml like this:
app:
image:
repository: myservice
tag: 1.2.3| Value | Default | Description |
|---|---|---|
name |
Release Name | The name of the service (used for app.kubernetes.io/name label) |
fullname |
Release Name (+ name) |
The name of the service instance (used for resource names and app.kubernetes.io/instance label) |
version |
same as image.tag |
The version of the service (used for app.kubernetes.io/version label) |
image.registry |
docker.io |
The Registry containing the image to run |
image.repository |
required | The name of the image image to run (without the Registry) |
image.tag |
required | The tag of the image to run; start with @ for digest instead of tag (e.g., @sha256:abc...) |
image.pullPolicy |
IfNotPresent |
Set to Always to try to pull new versions of the image |
image.pullSecret |
Name of the Kubernetes Secret providing credentials for pulling the image | |
securityContext.pod |
runtime default seccomp | Security context to use for the pod |
securityContext.container |
drop all capabilites | Security context to use for the container |
command |
[] |
Overrides the command to launch in the image |
args |
[] |
The command-line arguments passed to the service |
env |
{} |
Environment variables passed to the service as a key-value map |
envFrom |
{} |
Environment variables passed to the service from other sources (e.g., secretKeyRef) |
config |
{} |
YAML/JSON configuration to be mounted as a file in the container |
configMountPath |
/config/config.yaml |
The file path in the container to mount the data from config into (exposed via $CONFIG_FILE) |
additionalConfigs |
[] |
Additional ConfigMaps with key named data.yaml to be mounted (paths appended to $CONFIG_FILE) |
dnsConfig |
DNS config for the pod | |
startupProbe |
Probe that waits for the service to initially start up | |
livenessProbe |
Probe that causes the service to be restarted when failing | |
readinessProbe |
Probe that prevents the service from receiving traffic when failing | |
maxShutdownSeconds |
30 |
The number of seconds the pod has to shutdown before it is terminated |
labels |
{} |
Additional labels to set on all generated resources |
annotations |
{} |
Additional annotations to set on the Pod controller and Pods |
resources.requests.memory |
64Mi |
The amount of memory requested for the service (recommendation: slightly higher than average usage) |
resources.requests.cpu |
10m |
The number of CPU cores requested for the service |
resources.limits.memory |
96Mi |
The maximum amount of memory the service may use (recommendation: slightly higher than worst-case usage) |
resources.limits.cpu |
2000m |
The maximum number of CPU cores the service may use |
rollout.controller |
Deployment |
The type of Pod controller to create (Deployment, StatefulSet, DaemonSet or ArgoRollout) |
rollout.strategy |
RollingUpdate |
The rollout strategy (RollingUpdate, Recreate, OnDelete, Canary or BlueGreen) |
rollout.autoPromotion |
true |
Automatically promote rollouts (if rollout.strategy is BlueGreen and rollout.flagger if false) |
rollout.flagger |
false |
Use Flagger to control rollouts (rollout.controller must be Deployment or StatefulSet) |
rollout.analysis |
req. for Canary or Flagger | Flagger or Argo Rollouts analysis for automatic Canary or BlueGreen promotion |
rollout.revisionHistoryLimit |
null |
Number of old ReplicaSets to retain (rollout.controller must be Deployment or ArgoRollout) |
replicas |
1 |
The number of instances of the service to run (set at least 2 for Pod Disruption Budget) |
autoscaling.enabled |
false |
Enables automatic starting of additional instances |
autoscaling.maxReplicas |
3 |
The maximum number of instances to run (must be larger than replicas) |
autoscaling.metric.type |
Resource |
The type of metric to use for scaling (Resource, Pods, Object or External) |
autoscaling.metric.name |
cpu |
The name of the metric to use for scaling |
autoscaling.metric.object |
req. if type = Object |
Reference to the Kubernetes object the metric describes |
autoscaling.metric.selector |
{} |
Labels for selecting the metric as a key-value map |
autoscaling.targetValue |
80 |
The desired value of the metric to achieve through scaling (e.g., CPU utilization in percent) |
autoscaling.behavior |
{} |
Scaling behavior configuration (see HorizontalPodAutoscalerBehavior) |
scheduling.priority |
The name of the PriorityClass to use for scheduling this service |
|
scheduling.nodeSelector |
{} |
Labels to select nodes this service may be run on |
scheduling.nodePeferences |
{} |
Sets of label values to select nodes this service should be run on if possible |
scheduling.nodeExclusions |
{} |
Sets of label values to select nodes this service must not run on |
scheduling.tolerations |
[] |
Taints on nodes this service can tolerate |
scheduling.podAffinity |
{} |
Labels to select other pods this service should share nodes with if possible |
scheduling.podAntiAffinity |
{} |
Labels to select other pods this service must not share nodes with |
scheduling.replicaSpread |
BestEffort |
How to spread replicas across nodes (BestEffort, Strict, None) |
persistence.enabled |
false |
Enables persistent storage for the service |
persistence.storageClass |
The type of disk to use for storage instead of the cluster default | |
persistence.accessModes |
[ReadWriteOnce] |
The support access modes the volume can be mounted with |
persistence.size |
1G |
The size of the persistent volume to create for the service |
persistence.mountPath |
required if enabled | The mount path for the storage inside the container |
secrets.SECRET_NAME.mountPath |
required if used | The mount path for the Secret named SECRET_NAME (supports templating) inside the container |
secrets.SECRET_NAME.subPath |
The path of a single file in the Secret named SECRET_NAME to mount; leave empty to mount all files |
|
secrets.SECRET_NAME.files |
Map of file names to base64-encoded content; leave empty to reference existing Secret |
|
additionalMounts.PATH.name |
required if used | The name of an additional volume to be mounted at PATH inside the container |
additionalMounts.PATH.* |
required if used | The configuration for the additional volume (e.g., emptyDir: {}) |
ingress.enabled |
false |
Enables ingress into the service (either cluster-internal or public) |
ingress.port |
80 |
The container port ingress traffic is routed to |
ingress.protocol |
http |
The internal protocol used for ingress (e.g., http, https, h2c, grpc, http2/h2 or grpcs) |
ingress.timeoutSeconds |
Number of seconds after which to timeout waiting for response from service; -1 for infinite | |
ingress.domains |
[] |
The public domain names under which the service is exposed (leave empty for cluster-internal only) |
ingress.paths |
[] |
HTTP path prefixes to accept ingress traffic for (leave empty to accept traffic for any path) |
ingress.tls.enabled |
false |
Enables TLS termination at the ingress (not applicable if ingress.istio.enabled) |
ingress.tls.secret |
{{ .Release.Name }}-tls |
The name of the Secret holding the TLS private key (not applicable if ingress.istio.enabled) |
ingress.tls.secretNamespace |
The Kubernetes namespace containing the Secret (only applicable if ingress.class is contour) |
|
ingress.cors.enabled |
false |
Enables CORS (only applicable if ingress.class is nginx or ingress.istio.enabled is true) |
ingress.cors.allowOrigin |
[] |
List of origins allowed to access the ingress via CORS; leave empty to allow any |
ingress.cors.allowMethods |
[GET] |
List of HTTP methods allowed to access the ingress via CORS |
ingress.cors.allowHeaders |
[Content-Type] |
List of HTTP headers that can be used when requesting the ingress via CORS |
ingress.cors.allowCredentials |
true |
Indicates whether the caller is allowed to send the actual request (not the preflight) using credentials |
ingress.cors.exposeHeaders |
[] |
List of HTTP headers that the browsers are allowed to access |
ingress.class |
The ingress controller to use (not applicable if ingress.istio.enabled) |
|
ingress.annotations |
{} |
Annotations for Ingress or VirtualService resource |
ingress.headless |
false |
Creates an additional Service with the suffix -headless that directly exposes Pod IPs |
ingress.headlessExposesAll |
false |
Exposes all replicas, including unready ones, via the -headless Service |
ingress.nodeLocal |
false |
Creates an additional Service with the suffix -local that only routes to pods on the same node |
ingress.additionalSelectors |
{} |
Additional label selectors used to restrict the Pods selected by the Service |
ingress.istio.enabled |
false |
Use Istio VirtualService instead of Kubernetes Ingress resource |
ingress.istio.gateways |
[] |
The names of the Istio Gateways to use |
ingress.istio.httpHeaders |
{} |
Custom HTTP response headers |
ingress.istio.retries |
{} |
Istio retry policy |
ingress.extra.*.class |
same as ingress.class |
Additional ingress controller to use (not applicable if ingress.istio.enabled) |
ingress.extra.*.port |
same as ingress.port |
Additional container port ingress traffic is routed to (not applicable if ingress.istio.enabled) |
ingress.extra.*.protocol |
http |
The protocol used for the port (e.g., http, https, h2c, grpc, http2/h2 or grpcs) |
ingress.extra.*.timeoutSeconds |
Number of seconds after which to timeout waiting for response from service; -1 for infinite | |
ingress.extra.*.domains |
[] |
The public domain names under which the port is exposed (leave empty for cluster-internal only) |
ingress.extra.*.paths |
[] |
HTTP path prefixes to accept ingress traffic for (leave empty to accept traffic for any path) |
ingress.extra.*.tls.enabled |
false |
Enables TLS termination at the ingress |
ingress.extra.*.tls.secret |
Release Name + * + -tls |
The name of the Secret holding the TLS private key |
ingress.extra.*.tls.secretNamespace |
The Kubernetes namespace containing the Secret (only applicable if class is contour) |
|
ingress.extra.*.annotations |
{} |
Additional annotations, merged with ingress.annotations (use string nil to unset existing values) |
netpol.enabled |
false |
Apply network policies for the Pods |
netpol.ingress |
Allow from same namespace | Ingress network policy rules to apply |
netpol.egress |
[] |
Egress network policy rules to apply |
tracing.enabled |
false |
Enables tracing with OpenTelemetry or Jaeger agent (injected as sidecar) |
tracing.probability |
1 |
Probability of any single trace being sampled; can be overridden for incoming requests e.g. via Istio |
tracing.class |
Custom value to set for tracing sidecar injection annotations | |
monitoring.enabled |
false |
Use Prometheus for monitoring / metrics scraping |
monitoring.port |
9100 |
The port to be scraped for monitoring data |
monitoring.path |
/metrics |
The path to be scraped for monitoring data |
monitoring.interval |
1m |
The interval at which monitoring data is scraped |
alerting.enabled |
false |
Deploys Prometheus alert rule for issues like like unavailable pods or high memory use |
alerting.pod.maxStartupSeconds |
120 |
The maximum amount of time a Pod is allowed to take for startup |
alerting.pod.maxAgeSeconds |
The maximum allowed age of a Pod in seconds (useful to ensure regular deployments) |
|
alerting.restarts.enabled |
true |
Deploys Prometheus alert rule for unexpected container restarts |
alerting.memory.enabled |
true |
Enables alerts relating to memory usage |
alerting.memory.maxUsageFactor |
0.9 |
The maximum usage factor of the memory limit (between 0 and 1) |
alerting.memory.quotaBufferFactor |
1.0 |
Multiplied with resources.*.memory to determine minimum allowed unused memory quota in namespace |
alerting.cpu.sampleInterval |
1m |
The time interval in which to measure CPU usage |
alerting.cpu.maxThrottleFactor |
0.01 |
The maximum fraction of the container's execution time during which it experiences CPU throttling |
alerting.cpu.quotaBufferFactor |
1.0 |
Multiplied with resources.*.cpu to determine minimum allowed unused CPU quota in namespace |
alerting.http.sampleInterval |
20m |
The time interval in which to measure HTTP responses for triggering alerts |
alerting.http.referenceInterval |
1w |
The time interval to to compare with the sample interval to detect changes |
alerting.http.maxSlowdown |
2.5 |
The maximum HTTP response slowdown in the sample interval compared to the reference interval |
alerting.http.max4xxRatio |
2.5 |
The maximum HTTP 4xx ratio increase in the sample interval compared to the reference interval |
alerting.http.max5xxCount |
0 |
The maximum number of HTTP 5xx responses in the sample interval |
alerting.grpc.requestsMetric |
grpc_server_handled_total |
The name of the Prometheus metric counting gRPC requests |
alerting.grpc.sampleInterval |
20m |
The time interval in which to measure gRPC responses |
alerting.grpc.referenceInterval |
1w |
The time interval to to compare with the sample interval to detect changes |
alerting.grpc.maxErrorRatio |
2.5 |
The maximum gRPC error ratio increase in the sample interval compared to the reference interval |
alerting.grpc.errorDuration |
The duration for which the gRPC error rate has to remain elevated before triggering an alert | |
alerting.grpc.maxCriticalErrors |
0 |
The maximum number of critical gRPC errors responses in the sample interval |
alerting.grpc.criticalCodes |
[Internal, Unimplemented] |
Which gRPC status codes are considered critical errors |
alerting.logs.countInterval |
5m |
The time interval in which to count the number of messages per log level |
alerting.logs.levelLabel |
level |
The Loki label containing the log level |
alerting.logs.levels.*.maxCount |
0 |
The maximum number of messages of a specific log level in the interval to allow before alerting |
alerting.logs.levels.*.severity |
warning |
The severity of the alert when the maximum count of a messages of a specific log level is exceeded |
alerting.logs.levels.lokiConfigMap.label |
loki_rule |
The label attached to the ConfigMap holding the Loki Rules |
alerting.logs.levels.lokiConfigMap.labelValue |
"" |
The value of the label attached to the Loki Rule ConfigMap |
alerting.logs.levels.createLokiRule |
false |
Whether to create a LokiRule CR or not (useful when transitioning from loki-rule-operator) |
alerting.custom.*.metric |
required if used | The name of the Prometheus metric exposed by the service |
alerting.custom.*.labelMatchers |
Prometheus label matchers to use for filtering the metric (e.g., some_key="some_value") |
|
alerting.custom.*.aggregate |
required if used | The aggregate function to use to combine metric values from multiple replicas (e.g., max or sum) |
alerting.custom.*.increaseOver |
A sliding window in which to calculate the increase of the metric (e.g., 10m) |
|
alerting.custom.*.averageOver |
A sliding window in which to calculate the average value of the metric (e.g., 10m) |
|
alerting.custom.*.round |
false |
Round the result before evaluating the predicate |
alerting.custom.*.predicate |
required if used | An expression that triggers the alert when the metric fulfills it |
alerting.custom.*.severity |
warning |
The severity of the alert |
alerting.custom.*.topic |
The severity of the alert | |
alerting.custom.*.summary |
required if used | A short summary of the alert |
alerting.custom.*.description |
required if used | A longer description of the alert; can include metric labels via templating |
sidecars |
[] |
Additional sidecar containers to be added to the Pod |
sidecarTemplates |
[] |
Strings to be templated providing additional sidecar containers to be added to the Pod |
initContainers |
[] |
Additional init containers to be added to the Pod |
initContainerTemplates |
[] |
Strings to be templated providing additional init containers to be added to the Pod |
rbac.roles |
[] |
Namespace-specific Kubernetes RBAC Roles to assign to the service (supports templating) |
rbac.clusterRoles |
[] |
Cluster-wide Kubernetes RBAC Roles to assign to the service (supports templating) |
rbac.existingServiceAccount |
The name of an existing service account to use (instead of automatically creating one for the service) | |
global.alertLabels |
{} |
Additional labels to apply to alert rules |
global.grafana.url |
The URL of a Grafana instance with access to the service's metrics | |
global.grafana.dashboard |
qqsCbY5Zz |
The UID of the Grafana dashboard visualizing the service's metrics |
global.grafana.queryVariables |
{} |
Additional variables to be used in the to parametrize the service's Grafana dashboard |
In addition to the environment variables specified via the env value, the following dynamic environment variables are automatically set:
| Value | Description |
|---|---|
RELEASE_NAME |
The name of the Helm Release |
POD_CONTROLLER |
The value of rollout.controller |
POD_NAME |
The name of the Kubernetes pod |
POD_NAMESPACE |
The namespace of the Kubernetes pod |
POD_IP |
The cluster-internal IP of the Kubernetes pod |
NODE_NAME |
The name of the Kubernetes node the pod is running on |
REPLICAS |
The desired number of instances of the service that should be running (unset if autoscaling.enabled is true) |
CONFIG_FILE |
:-separated list of paths of mounted YAML/JSON config files |
PORT |
The ingress.port (if ingress.enabled is true) |
METRICS_PORT |
The monitoring.port (if monitoring.enabled is true) |
OTEL_* |
OpenTelemetry client configuration (if tracing.enabled is true) |
JAEGER_* |
Jaeger client configuration (if tracing.enabled is true) |
This Helm chart generates a number of Resources based on the specified Values. These resources reference each other:
Legend:
Deployment
Instructs Kubernetes to create a certain number of Pods (replicas) running a specific image.
Service
Created if ingress.enabled or monitoring.enabled is true.
Ingress
Created if ingress.enabled is true, ingress.domains is not empty and ingress.istio.enabled is false.
VirtualService
Created if ingress.enabled and ingress.istio.enabled are both true.
PodMonitor
Created if monitoring.enabled is true.
PrometheusRule
Created if alerting.enabled is true.
ConfigMap
Created if config is not empty.
PersistentVolumeClaim
Created if persistence.enabled is true.
ServiceAccount
Created if rbac.roles and/or rbac.clusterRoles is not empty.
RoleBinding
Created once for every entry in rbac.roles.
ClusterRoleBinding
Created once for every entry in rbac.clusterRoles.
PodDisruptionBudget
Created if replicas is greater than 1.
HorizontalPodAutoscaler
Created if autoscaling.enabled is true.