From 10eb55f7962f6fa0bfc3ff5a3cea83854ee3908b Mon Sep 17 00:00:00 2001
From: Frederic Branczyk <fbranczyk@gmail.com>
Date: Wed, 29 Apr 2020 16:50:33 +0200
Subject: [PATCH] receive: Use anti-affinity to spread across zones

Signed-off-by: Frederic Branczyk <fbranczyk@gmail.com>
---
 CHANGELOG.md                                          |  2 ++
 .../all/manifests/thanos-receive-statefulSet.yaml     | 11 +++++++++++
 jsonnet/kube-thanos/kube-thanos-receive.libsonnet     | 10 ++++++++++
 3 files changed, 23 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 319f1b73..2eaed2ad 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,8 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 
 - [#105](https://github.com/thanos-io/kube-thanos/pull/105) compactor, store: Add deduplication replica label flags and delete delay labels
 
+- [#119](https://github.com/thanos-io/kube-thanos/pull/119) receive: Distribute receive instances across node zones via pod anti affinity (note: only available on 1.17+).
+
 ### Fixed
 
 -
diff --git a/examples/all/manifests/thanos-receive-statefulSet.yaml b/examples/all/manifests/thanos-receive-statefulSet.yaml
index 1cb35baa..74c4b6ce 100644
--- a/examples/all/manifests/thanos-receive-statefulSet.yaml
+++ b/examples/all/manifests/thanos-receive-statefulSet.yaml
@@ -38,6 +38,17 @@ spec:
               - thanos
               topologyKey: kubernetes.io/hostname
             weight: 100
+          - podAffinityTerm:
+              labelSelector:
+                matchExpressions:
+                - key: app.kubernetes.io/instance
+                  operator: In
+                  values:
+                  - thanos-receive
+              namespaces:
+              - thanos
+              topologyKey: topology.kubernetes.io/zone
+            weight: 100
       containers:
       - args:
         - receive
diff --git a/jsonnet/kube-thanos/kube-thanos-receive.libsonnet b/jsonnet/kube-thanos/kube-thanos-receive.libsonnet
index 10e0ca24..d9633ed9 100644
--- a/jsonnet/kube-thanos/kube-thanos-receive.libsonnet
+++ b/jsonnet/kube-thanos/kube-thanos-receive.libsonnet
@@ -119,6 +119,16 @@ local k = import 'ksonnet/ksonnet.beta.4/k.libsonnet';
         matchExpression.withOperator('In') +
         matchExpression.withValues([tr.statefulSet.metadata.labels['app.kubernetes.io/instance']]),
       ]),
+      affinity.new() +
+      affinity.withWeight(100) +
+      affinity.mixin.podAffinityTerm.withNamespaces(tr.config.namespace) +
+      affinity.mixin.podAffinityTerm.withTopologyKey('topology.kubernetes.io/zone') +
+      affinity.mixin.podAffinityTerm.labelSelector.withMatchExpressions([
+        matchExpression.new() +
+        matchExpression.withKey('app.kubernetes.io/instance') +
+        matchExpression.withOperator('In') +
+        matchExpression.withValues([tr.statefulSet.metadata.labels['app.kubernetes.io/instance']]),
+      ]),
     ]) +
     sts.mixin.spec.selector.withMatchLabels(tr.config.podLabelSelector) +
     {