Add Sidecar
Add a sidecar to workloads using the workload resource
The
workload
Resource Type can be used to make updates to resources before they are deployed into the cluster. In this example, a Resource Definition implementing the workload Resource Type is used to inject the Open Telemetry agent as a sidecar into every workload. In addition to adding the sidecar, it also adds an environment variable called OTEL_EXPORTER_OTLP_ENDPOINT to each container running in the workload.
Resource Definitions
otel-sidecar.yaml
(
view on GitHub
)
:
apiVersion: entity.humanitec.io/v1b1
kind: Definition
metadata:
id: otel-sidecar
entity:
name: otel-sidecar
type: workload
driver_type: humanitec/template
driver_inputs:
values:
templates:
outputs: |
{{- /*
The "update" output is passed into the corresponding "update" output of the "workload" Resource Type.
*/ -}}
update:
{{- /*
Add the variable OTEL_EXPORTER_OTLP_ENDPOINT to all containers
*/ -}}
{{- range $containerId, $value := .resource.spec.containers }}
- op: add
path: /spec/containers/{{ $containerId }}/variables/OTEL_EXPORTER_OTLP_ENDPOINT
value: http://localhost:4317
{{- end }}
manifests:
sidecar.yaml:
location: containers
data: |
{{- /*
The Open Telemetry container as a sidecar in the workload
*/ -}}
command:
- "/otelcol"
- "--config=/conf/otel-agent-config.yaml"
image: otel/opentelemetry-collector:0.94.0
name: otel-agent
resources:
limits:
cpu: 500m
memory: 500Mi
requests:
cpu: 100m
memory: 100Mi
ports:
- containerPort: 55679 # ZPages endpoint.
- containerPort: 4317 # Default OpenTelemetry receiver port.
- containerPort: 8888 # Metrics.
env:
- name: GOMEMLIMIT
value: 400MiB
volumeMounts:
- name: otel-agent-config-vol
mountPath: /conf
sidecar-volume.yaml:
location: volumes
data: |
{{- /*
A volume that is used to surface the config file
*/ -}}
configMap:
name: otel-agent-conf-{{ .id }}
items:
- key: otel-agent-config
path: otel-agent-config.yaml
name: otel-agent-config-vol
otel-config-map.yaml:
location: namespace
data: |
{{- /*
The config file for the Open Telemetry agent. Notice that it's name includes the GUResID
*/ -}}
apiVersion: v1
kind: ConfigMap
metadata:
name: otel-agent-conf-{{ .id }}
labels:
app: opentelemetry
component: otel-agent-conf
data:
otel-agent-config: |
receivers:
otlp:
protocols:
grpc:
endpoint: localhost:4317
http:
endpoint: localhost:4318
exporters:
otlp:
endpoint: "otel-collector.default:4317"
tls:
insecure: true
sending_queue:
num_consumers: 4
queue_size: 100
retry_on_failure:
enabled: true
processors:
batch:
memory_limiter:
# 80% of maximum memory up to 2G
limit_mib: 400
# 25% of limit up to 2G
spike_limit_mib: 100
check_interval: 5s
extensions:
zpages: {}
service:
extensions: [zpages]
pipelines:
traces:
receivers: [otlp]
processors: [memory_limiter, batch]
exporters: [otlp]
criteria: []
otel-sidecar.tf
(
view on GitHub
)
:
resource "humanitec_resource_definition" "otel-sidecar" {
driver_type = "humanitec/template"
id = "otel-sidecar"
name = "otel-sidecar"
type = "workload"
driver_inputs = {
values_string = jsonencode({
"templates" = {
"outputs" = <<END_OF_TEXT
{{- /*
The "update" output is passed into the corresponding "update" output of the "workload" Resource Type.
*/ -}}
update:
{{- /*
Add the variable OTEL_EXPORTER_OTLP_ENDPOINT to all containers
*/ -}}
{{- range $containerId, $value := .resource.spec.containers }}
- op: add
path: /spec/containers/{{ $containerId }}/variables/OTEL_EXPORTER_OTLP_ENDPOINT
value: http://localhost:4317
{{- end }}
END_OF_TEXT
"manifests" = {
"sidecar.yaml" = {
"location" = "containers"
"data" = <<END_OF_TEXT
{{- /*
The Open Telemetry container as a sidecar in the workload
*/ -}}
command:
- "/otelcol"
- "--config=/conf/otel-agent-config.yaml"
image: otel/opentelemetry-collector:0.94.0
name: otel-agent
resources:
limits:
cpu: 500m
memory: 500Mi
requests:
cpu: 100m
memory: 100Mi
ports:
- containerPort: 55679 # ZPages endpoint.
- containerPort: 4317 # Default OpenTelemetry receiver port.
- containerPort: 8888 # Metrics.
env:
- name: GOMEMLIMIT
value: 400MiB
volumeMounts:
- name: otel-agent-config-vol
mountPath: /conf
END_OF_TEXT
}
"sidecar-volume.yaml" = {
"location" = "volumes"
"data" = <<END_OF_TEXT
{{- /*
A volume that is used to surface the config file
*/ -}}
configMap:
name: otel-agent-conf-{{ .id }}
items:
- key: otel-agent-config
path: otel-agent-config.yaml
name: otel-agent-config-vol
END_OF_TEXT
}
"otel-config-map.yaml" = {
"location" = "namespace"
"data" = <<END_OF_TEXT
{{- /*
The config file for the Open Telemetry agent. Notice that it's name includes the GUResID
*/ -}}
apiVersion: v1
kind: ConfigMap
metadata:
name: otel-agent-conf-{{ .id }}
labels:
app: opentelemetry
component: otel-agent-conf
data:
otel-agent-config: |
receivers:
otlp:
protocols:
grpc:
endpoint: localhost:4317
http:
endpoint: localhost:4318
exporters:
otlp:
endpoint: "otel-collector.default:4317"
tls:
insecure: true
sending_queue:
num_consumers: 4
queue_size: 100
retry_on_failure:
enabled: true
processors:
batch:
memory_limiter:
# 80% of maximum memory up to 2G
limit_mib: 400
# 25% of limit up to 2G
spike_limit_mib: 100
check_interval: 5s
extensions:
zpages: {}
service:
extensions: [zpages]
pipelines:
traces:
receivers: [otlp]
processors: [memory_limiter, batch]
exporters: [otlp]
END_OF_TEXT
}
}
}
})
}
}