ptzagk / kube-thanos

Kubernetes specific configuration for deploying Thanos.

kube-thanos

Note that everything is experimental and may change significantly at any time.

This repository collects Kubernetes manifests combined with documentation and scripts to provide easy to deploy experience for Thanos on Kubernetes.

The content of this project is written in jsonnet. This project could both be described as a package as well as a library.

Prerequisites

kind

In order to just try out this stack, start kind with the following command:

$ kind create cluster

Quickstart

This project is intended to be used as a library (i.e. the intent is not for you to create your own modified copy of this repository).

Though for a quickstart a compiled version of the Kubernetes manifests generated with this library (specifically with example.jsonnet) is checked into this repository in order to try the content out quickly. To try out the stack un-customized run:

• Simply create the stack:

$ kubectl create -f manifests/

• And to teardown the stack:

$ kubectl delete -f manifests/

Customizing kube-thanos

This section:

• describes how to customize the kube-thanos library via compiling the kube-thanos manifests yourself (as an alternative to the Quickstart section).
• still doesn't require you to make a copy of this entire repository, but rather only a copy of a few select files.

Installing

The content of this project consists of a set of jsonnet files making up a library to be consumed.

Install this library in your own project with jsonnet-bundler (the jsonnet package manager):

$ mkdir my-kube-thanos; cd my-kube-thanos
$ jb init  # Creates the initial/empty `jsonnetfile.json`
# Install the kube-thanos dependency
$ jb install github.com/thanos-io/kube-thanos/jsonnet/kube-thanos@main # Creates `vendor/` & `jsonnetfile.lock.json`, and fills in `jsonnetfile.json`

jb can be installed with go get github.com/jsonnet-bundler/jsonnet-bundler/cmd/jb

An e.g. of how to install a given version of this library: jb install github.com/thanos-io/kube-thanos/jsonnet/kube-thanos@main

In order to update the kube-thanos dependency, simply use the jsonnet-bundler update functionality:

$ jb update

Compiling

e.g. of how to compile the manifests: ./build.sh example.jsonnet

before compiling, install gojsontoyaml tool with go get github.com/brancz/gojsontoyaml

Here's example.jsonnet:

local t = import 'kube-thanos/thanos.libsonnet';

// For an example with every option and component, please check all.jsonnet

local commonConfig = {
  config+:: {
    local cfg = self,
    namespace: 'thanos',
    version: 'v0.22.0',
    image: 'quay.io/thanos/thanos:' + cfg.version,
    objectStorageConfig: {
      name: 'thanos-objectstorage',
      key: 'thanos.yaml',
    },
    hashringConfigMapName: 'hashring-config',
    volumeClaimTemplate: {
      spec: {
        accessModes: ['ReadWriteOnce'],
        resources: {
          requests: {
            storage: '10Gi',
          },
        },
      },
    },
  },
};

local i = t.receiveIngestor(commonConfig.config {
  replicas: 1,
  replicaLabels: ['receive_replica'],
  replicationFactor: 1,
  // Disable shipping to object storage for the purposes of this example
  objectStorageConfig: null,
});

local r = t.receiveRouter(commonConfig.config {
  replicas: 1,
  replicaLabels: ['receive_replica'],
  replicationFactor: 1,
  // Disable shipping to object storage for the purposes of this example
  objectStorageConfig: null,
  endpoints: i.endpoints,
});

local s = t.store(commonConfig.config {
  replicas: 1,
  serviceMonitor: true,
});

local q = t.query(commonConfig.config {
  replicas: 1,
  replicaLabels: ['prometheus_replica', 'rule_replica'],
  serviceMonitor: true,
  stores: [s.storeEndpoint] + i.storeEndpoints,
});

{ ['thanos-store-' + name]: s[name] for name in std.objectFields(s) } +
{ ['thanos-query-' + name]: q[name] for name in std.objectFields(q) } +
{ ['thanos-receive-router-' + resource]: r[resource] for resource in std.objectFields(r) } +
{ ['thanos-receive-ingestor-' + resource]: i[resource] for resource in std.objectFields(i) if resource != 'ingestors' } +
{
  ['thanos-receive-ingestor-' + hashring + '-' + resource]: i.ingestors[hashring][resource]
  for hashring in std.objectFields(i.ingestors)
  for resource in std.objectFields(i.ingestors[hashring])
  if i.ingestors[hashring][resource] != null
}

And here's the build.sh script (which uses vendor/ to render all manifests in a json structure of {filename: manifest-content}):

#!/usr/bin/env bash

# This script uses arg $1 (name of *.jsonnet file to use) to generate the manifests/*.yaml files.

set -e
set -x
# only exit with zero if all commands of the pipeline exit successfully
set -o pipefail

JSONNET=${JSONNET:-jsonnet}
GOJSONTOYAML=${GOJSONTOYAML:-gojsontoyaml}

# Make sure to start with a clean 'manifests' dir
rm -rf manifests
mkdir manifests

# optional, but we would like to generate yaml, not json
${JSONNET} -J vendor -m manifests "${1-example.jsonnet}" | xargs -I{} sh -c "cat {} | ${GOJSONTOYAML} > {}.yaml; rm -f {}" -- {}
find manifests -type f ! -name '*.yaml' -delete

# The following script generates all components, mostly used for testing

rm -rf examples/all/manifests
mkdir examples/all/manifests

${JSONNET} -J vendor -m examples/all/manifests "${1-all.jsonnet}" | xargs -I{} sh -c "cat {} | ${GOJSONTOYAML} > {}.yaml; rm -f {}" -- {}
find examples/all/manifests -type f ! -name '*.yaml' -delete

Note you need jsonnet (go get github.com/google/go-jsonnet/cmd/jsonnet) and gojsontoyaml (go get github.com/brancz/gojsontoyaml) installed to run build.sh. If you just want json output, not yaml, then you can skip the pipe and everything afterwards.

This script runs the jsonnet code, then reads each key of the generated json and uses that as the file name, and writes the value of that key to that file, and converts each json manifest to yaml.

Apply the kube-thanos stack

The previous steps (compilation) has created a bunch of manifest files in the manifest/ folder. Now simply use kubectl to install Thanos as per your configuration:

$ kubectl apply -f manifests/

Check the monitoring namespace (or the namespace you have specific in namespace: ) and make sure the pods are running.