KubraGen Builder: Loki Stack
kg_lokistack is a builder for KubraGen that deploys
a Loki Stack stack in Kubernetes.
The Loki Stack consists of Loki, Promtail and Grafana (optional).
KubraGen is a Kubernetes YAML generator library that makes it possible to generate
configurations using the full power of the Python programming language.
Example
from kg_loki import LokiConfigFile, LokiConfigFileOptions
from kubragen import KubraGen
from kubragen.consts import PROVIDER_GOOGLE, PROVIDERSVC_GOOGLE_GKE
from kubragen.object import Object
from kubragen.option import OptionRoot
from kubragen.options import Options
from kubragen.output import OutputProject, OD_FileTemplate, OutputFile_ShellScript, OutputFile_Kubernetes, \
OutputDriver_Print
from kubragen.provider import Provider
from kg_lokistack import LokiStackBuilder, LokiStackOptions
kg = KubraGen(provider=Provider(PROVIDER_GOOGLE, PROVIDERSVC_GOOGLE_GKE), options=Options({
'namespaces': {
'mon': 'app-monitoring',
},
}))
out = OutputProject(kg)
shell_script = OutputFile_ShellScript('create_gke.sh')
out.append(shell_script)
shell_script.append('set -e')
file = OutputFile_Kubernetes('app-namespace.yaml')
file.append([
Object({
'apiVersion': 'v1',
'kind': 'Namespace',
'metadata': {
'name': 'app-monitoring',
},
}, name='ns-monitoring', source='app', instance='app')
])
out.append(file)
shell_script.append(OD_FileTemplate(f'kubectl apply -f ${{FILE_{file.fileid}}}'))
shell_script.append(f'kubectl config set-context --current --namespace=app-monitoring')
lokiconfigfile = LokiConfigFile(options=LokiConfigFileOptions({
}))
lokistack_config = LokiStackBuilder(kubragen=kg, options=LokiStackOptions({
'namespace': OptionRoot('namespaces.mon'),
'basename': 'mylokistack',
'config': {
'loki': {
'loki_config': lokiconfigfile,
},
'grafana': {
'admin': {
'user': 'myuser',
'password': 'mypassword',
},
}
},
'kubernetes': {
'volumes': {
'loki-data': {
'persistentVolumeClaim': {
'claimName': 'lokistack-storage-claim'
}
}
},
'resources': {
'loki-statefulset': {
'requests': {
'cpu': '150m',
'memory': '300Mi'
},
'limits': {
'cpu': '300m',
'memory': '450Mi'
},
},
},
}
}))
lokistack_config.ensure_build_names(lokistack_config.BUILD_ACCESSCONTROL, lokistack_config.BUILD_CONFIG,
lokistack_config.BUILD_SERVICE)
file = OutputFile_Kubernetes('lokistack-config.yaml')
out.append(file)
file.append(lokistack_config.build(lokistack_config.BUILD_ACCESSCONTROL, lokistack_config.BUILD_CONFIG))
shell_script.append(OD_FileTemplate(f'kubectl apply -f ${{FILE_{file.fileid}}}'))
file = OutputFile_Kubernetes('lokistack.yaml')
out.append(file)
file.append(lokistack_config.build(lokistack_config.BUILD_SERVICE))
shell_script.append(OD_FileTemplate(f'kubectl apply -f ${{FILE_{file.fileid}}}'))
out.output(OutputDriver_Print())
Output:
****** BEGIN FILE: 001-app-namespace.yaml ********
apiVersion: v1
kind: Namespace
metadata:
name: app-monitoring
****** END FILE: 001-app-namespace.yaml ********
****** BEGIN FILE: 002-lokistack-config.yaml ********
apiVersion: v1
kind: ServiceAccount
metadata:
name: mylokistack
namespace: app-monitoring
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: mylokistack-promtail
rules:
- apiGroups: ['']
resources: [nodes, nodes/proxy, services, endpoints, pods]
verbs: [get, watch, list]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: mylokistack-promtail
subjects:
- kind: ServiceAccount
name: mylokistack
namespace: app-monitoring
<...more...>
****** END FILE: 002-lokistack-config.yaml ********
****** BEGIN FILE: 003-lokistack.yaml ********
apiVersion: v1
kind: Service
metadata:
name: mylokistack-loki-headless
namespace: app-monitoring
labels:
app: mylokistack-loki
spec:
clusterIP: None
ports:
- port: 3100
protocol: TCP
name: http-metrics
targetPort: http-metrics
selector:
app: mylokistack-loki
---
apiVersion: v1
kind: Service
metadata:
name: mylokistack-loki
<...more...>
****** END FILE: 003-lokistack.yaml ********
****** BEGIN FILE: create_gke.sh ********
#!/bin/bash
set -e
kubectl apply -f 001-app-namespace.yaml
kubectl config set-context --current --namespace=app-monitoring
kubectl apply -f 002-lokistack-config.yaml
kubectl apply -f 003-lokistack.yaml
****** END FILE: create_gke.sh ********
Credits
based on
Install Loki with Helm
Author
Rangel Reale (rangelreale@gmail.com)