Mariadb max_packet_allowed variable exposed (#295)

* Mariadb max_packet_allowed - Draft

* Draft 2 - max_packet_now has default env but still NOT dynamic. Confd env values ignored

* Variable rename and README update per Comment 1

* Renamed confd cnf files with correct uid settings

* Remove errant comment

* Remove three unneeded files

* Remove extra set-max-packet directories and files

* Missing toml value fixed

* Quotes for perm values removed by mistake

Author: Gavin Morris

mariadb/Dockerfile

@@ -23,5 +23,7 @@ RUN --mount=type=cache,id=mariadb-apk-${TARGETARCH},sharing=locked,target=/var/c
 # base image. Set to 10 minutes just incase it ran on very old or overallocated
 # hardware.
 ENV S6_CMD_WAIT_FOR_SERVICES_MAXTIME=600000
+# Default Mariadb value of 16 MB (bytes)
+ENV MYSQL_MAX_ALLOWED_PACKET=16777216
 
 COPY --link rootfs /

mariadb/README.md

@@ -41,6 +41,7 @@ default database connection configuration.
 | :------------------- | :------ | :------------------------------------------------------------------------------------ |
 | MYSQL_ROOT_PASSWORD  |         | The database root user password. Defaults to `DB_ROOT_PASSWORD`                       |
 | MYSQL_ROOT_USER      |         | The database root user (used to create the site database). Defaults to `DB_ROOT_USER` |
+| MYSQL_MAX_ALLOWED_PACKET | 16777216 | Max packet length to send to or receive from the server, [documentation](https://mariadb.com/docs/server/ref/mdb/system-variables/max_allowed_packet/) |
 
 ## Logs
 

mariadb/rootfs/etc/confd/conf.d/mariadb-server.cnf.toml

@@ -0,0 +1,7 @@
+[template]
+src = "mariadb-server.cnf.tmpl"
+dest = "/etc/my.cnf.d/mariadb-server.cnf"
+uid = 0
+gid = 0
+mode = "0664"
+keys = [ "/" ]

mariadb/rootfs/etc/my.cnf.d/mariadb-server.cnf renamed to mariadb/rootfs/etc/confd/templates/mariadb-server.cnf.tmpl

@@ -8,7 +8,7 @@
 # this is only for the mysqld standalone daemon
 [mysqld]
 # skip-networking
-
+max_allowed_packet ={{ getenv "MYSQL_MAX_ALLOWED_PACKET" }}
 # Galera-related settings
 [galera]
 # Mandatory settings