From 3799ee0bd52a72b668f640430873ec1e2d819b43 Mon Sep 17 00:00:00 2001
From: Kai Moritz <kai@juplo.de>
Date: Sun, 15 Jan 2023 17:27:10 +0100
Subject: [PATCH] feat: Working config for HAProxy mit mapping via `X-Shard`
 (casesensitive!)

---
 docker-compose.yml | 22 +++++++++++++++-------
 haproxy.cfg        | 21 +++++++++++++++------
 sharding.map       | 10 ++++++++++
 3 files changed, 40 insertions(+), 13 deletions(-)
 create mode 100644 sharding.map

diff --git a/docker-compose.yml b/docker-compose.yml
index 6d093704..28fca8b5 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -88,18 +88,26 @@ services:
     image: haproxy:2.7
     volumes:
       - ./haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg:ro
+      - ./sharding.map:/usr/local/etc/haproxy/sharding.map:ro
     sysctls:
       net.ipv4.ip_unprivileged_port_start: 0
     ports:
-      - 8080:80
+      - 8080:8400
+      - 8401:8401
       - 8404:8404
 
-  web1:
-    image: nginx:1.17
-  web2:
-    image: nginx:1.17
-  web3:
-    image: nginx:1.17
+  backend-1:
+    image: jmalloc/echo-server:latest
+    ports:
+      - 8081:8080
+  backend-2:
+    image: jmalloc/echo-server:latest
+    ports:
+      - 8082:8080
+  backend-3:
+    image: jmalloc/echo-server:latest
+    ports:
+      - 8083:8080
 
   setup:
     image: juplo/toolbox
diff --git a/haproxy.cfg b/haproxy.cfg
index f334457c..0dd9ac52 100644
--- a/haproxy.cfg
+++ b/haproxy.cfg
@@ -7,6 +7,10 @@ defaults
   timeout http-request 10s
   log global
 
+global
+  stats socket ipv4@:8401 level admin
+  stats timeout 2m
+
 frontend stats
   bind *:8404
   stats enable
@@ -14,10 +18,15 @@ frontend stats
   stats refresh 10s
 
 frontend frontend
-  bind :80
-  default_backend webservers
+  bind :8400
+  use_backend %[req.hdr(X-Shard),map(/usr/local/etc/haproxy/sharding.map)]
+
+backend backend_1
+  server b1 backend-1:8080 check
+
+backend backend_2
+  server b2 backend-2:8080 check
+
+backend backend_3
+  server b3 backend-3:8080 check
 
-backend webservers
-  server s1 web1:80 check
-  server s2 web2:80 check
-  server s3 web3:80 check
diff --git a/sharding.map b/sharding.map
new file mode 100644
index 00000000..ffdbb6cb
--- /dev/null
+++ b/sharding.map
@@ -0,0 +1,10 @@
+0 backend_3
+1 backend_1
+2 backend_2
+3 backend_3
+4 backend_1
+5 backend_2
+6 backend_3
+7 backend_1
+8 backend_2
+9 backend_3
-- 
2.20.1