18 releases (6 stable)

1.1.2 Mar 2, 2022
1.0.1 Nov 4, 2021
1.0.0 Jun 1, 2021
0.4.3 Feb 13, 2021
0.1.0 Dec 3, 2018

#923 in Database interfaces

Download history 1/week @ 2024-02-20 4/week @ 2024-02-27 19/week @ 2024-03-26 62/week @ 2024-04-02

53 downloads per month

BSD-3-Clause

21KB
205 lines

httpwsrep

HTTP status codes for galera cluster

crates.io build

example

This helps to check the galera cluster using HAProxy - option httpchk which queries the galera node and gets its current state from: SHOW STATUS LIKE 'wsrep_local_state';

if wsrep_local_state == 4 it will return HTTP 200 OK, otherwise HTTP 503 Service Unavailable

The posible values for wsrep_local_state are:

Num Comment Description
1 Joining Node is joining the cluster
2 Donor/Desynced Node is the donor to the node joining the cluster
3 Joined Node has joined the cluster
4 Synced Node is synced with the cluster

HAProxy example

backend galera
    mode tcp
    option httpchk
    default-server check port 9200
    server node0 10.0.0.1:3306
    server node1 10.0.0.2:3306
    server node2 10.0.0.3:3306

httpwsrep

You need to run httpwsrep in each galera node preferably using a supervisor, for example if using immortal you could create /usr/local/etc/immortal/httpwsrep.yml with something like this:

cmd: /path/to/httpwsrep
env:
    DSN: mysql://haproxy@tcp(10.0.0.1:3306)/
log:
    file: /var/log/httpwsrep.log

a valid mysql user needs to be created, in this case the user is haproxy

By default port 9200 is used but if required can change it using option --port

metrics

You can use Prometheus and query the endpoint: /metrics

Dependencies

~23–39MB
~633K SLoC