mariadb: add MARIADB_* environment variables from #333

grooverdan · grooverdan · commit e0b7760e77b7 · 2021-03-01T17:42:43.000+11:00
diff --git a/mariadb/content.md b/mariadb/content.md
@@ -13,7 +13,7 @@ The intent is also to maintain high compatibility with MySQL, ensuring a library
 Starting a MariaDB instance is simple:
 
 ```console
-$ docker run --port 127.0.0.1:3306:3306  --name some-%%REPO%% -e MYSQL_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
+$ docker run --port 127.0.0.1:3306:3306  --name some-%%REPO%% -e MARIADB_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
 ```
 
 or:
@@ -68,7 +68,7 @@ The startup configuration is specified in the file `/etc/mysql/my.cnf`, and that
 If `/my/custom/config-file.cnf` is the path and name of your custom configuration file, you can start your `%%IMAGE%%` container like this (note that only the directory path of the custom config file is used in this command):
 
 ```console
-$ docker run --name some-%%REPO%% -v /my/custom:/etc/mysql/conf.d -e MYSQL_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
+$ docker run --name some-%%REPO%% -v /my/custom:/etc/mysql/conf.d -e MARIADB_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
 ```
 
 This will start a new container `some-%%REPO%%` where the MariaDB instance uses the combined startup settings from `/etc/mysql/my.cnf` and `/etc/mysql/conf.d/config-file.cnf`, with settings from the latter taking precedence.
@@ -89,31 +89,39 @@ $ docker run -it --rm %%IMAGE%%:tag --verbose --help
 
 ## Environment Variables
 
-When you start the `%%IMAGE%%` image, you can adjust the configuration of the MariaDB instance by passing one or more environment variables on the `docker run` command line. Do note that none of the variables below will have any effect if you start the container with a data directory that already contains a database: any pre-existing database will always be left untouched on container startup.
+When you start the `%%IMAGE%%` image, you can adjust the initialization of the MariaDB instance by passing one or more environment variables on the `docker run` command line. Do note that none of the variables below will have any effect if you start the container with a data directory that already contains a database: any pre-existing database will always be left untouched on container startup.
 
-### `MYSQL_ROOT_PASSWORD`
+From tags 10.2.38, 10.3.29, 10.4.19, 10.5.10 onwards, and all 10.6 tags, the `MARIADB_*` equivalent variables are provided. `MARIADB_*` variants will always be used in preference to `MYSQL_*` variants.
 
-This variable is mandatory and specifies the password that will be set for the MariaDB `root` superuser account. In the above example, it was set to `my-secret-pw`.
+One of `MARIADB_ROOT_PASSWORD`, `MARIADB_ALLOW_EMPTY_ROOT_PASSWORD`, or `MARIADB_RANDOM_ROOT_PASSWORD` (or equivalents, including `*_FILE`), is required. The other environment variables are optional.
 
-### `MYSQL_DATABASE`
+### `MARIADB_ROOT_PASSWORD` / `MYSQL_ROOT_PASSWORD`
 
-This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](http://dev.mysql.com/doc/en/adding-users.html)) to this database.
+This specifies the password that will be set for the MariaDB `root` superuser account. In the above example, it was set to `my-secret-pw`.
 
-### `MYSQL_USER`, `MYSQL_PASSWORD`
+### `MARIADB_ALLOW_EMPTY_ROOT_PASSWORD` / `MYSQL_ALLOW_EMPTY_PASSWORD`
 
-These variables are optional, used in conjunction to create a new user and to set that user's password. This user will be granted superuser permissions (see above) for the database specified by the `MYSQL_DATABASE` variable. Both variables are required for a user to be created.
+Set to a non-empty value, like `yes`, to allow the container to be started with a blank password for the root user. *NOTE*: Setting this variable to `yes` is not recommended unless you really know what you are doing, since this will leave your MariaDB instance completely unprotected, allowing anyone to gain complete superuser access.
 
-Do note that there is no need to use this mechanism to create the root superuser, that user gets created by default with the password specified by the `MYSQL_ROOT_PASSWORD` variable.
+### `MARIADB_DATABASE` / `MYSQL_DATABASE`
 
-### `MYSQL_ALLOW_EMPTY_PASSWORD`
+This variable is optional and allows you to specify the name of a database to be created on image startup. If a user/password was supplied (see below) then that user will be granted superuser access ([corresponding to `GRANT ALL`](https://mariadb.com/kb/en/grant/#the-all-privileges-privilege)) to this database.
+
+### `MARIADB_USER` / `MYSQL_USER`,  `MARIADB_PASSWORD` / `MYSQL_PASSWORD`
+
+These variables are optional, used in conjunction to create a new user and to set that user's password. This user will be granted superuser permissions (see above) for the database specified by the `MARIADB_DATABASE` / `MYSQL_DATABASE` variable. Both user and password variables are required for a user to be created.
+
+Do note that there is no need to use this mechanism to create the root superuser, that user gets created by default with the password specified by the `MARIADB_ROOT_PASSWORD` / `MYSQL_ROOT_PASSWORD` variable.
+
+### `MARIADB_ALLOW_EMPTY_PASSWORD` / `MYSQL_ALLOW_EMPTY_PASSWORD`
 
 This is an optional variable. Set to a non-empty value, like `yes`, to allow the container to be started with a blank password for the root user. *NOTE*: Setting this variable to `yes` is not recommended unless you really know what you are doing, since this will leave your MariaDB instance completely unprotected, allowing anyone to gain complete superuser access.
 
-### `MYSQL_RANDOM_ROOT_PASSWORD`
+### `MARIADB_ROOT_PASSWORD` / `MYSQL_RANDOM_ROOT_PASSWORD`
 
-This is an optional variable. Set to a non-empty value, like `yes`, to generate a random initial password for the root user (using `pwgen`). The generated root password will be printed to stdout (`GENERATED ROOT PASSWORD: .....`).
+This is an optional variable. Set to a non-empty value, like `yes`, to generate a random initial password for the root user. The generated root password will be printed to stdout (`GENERATED ROOT PASSWORD: .....`).
 
-### `MYSQL_INITDB_SKIP_TZINFO`
+### `MARIADB_INITDB_SKIP_TZINFO` / `MYSQL_INITDB_SKIP_TZINFO`
 
 By default, the entrypoint script automatically loads the timezone data needed for the `CONVERT_TZ()` function. If it is not needed, any non-empty value disables timezone loading.
 
@@ -122,14 +130,14 @@ By default, the entrypoint script automatically loads the timezone data needed f
 As an alternative to passing sensitive information via environment variables, `_FILE` may be appended to the previously listed environment variables, causing the initialization script to load the values for those variables from files present in the container. In particular, this can be used to load passwords from Docker secrets stored in `/run/secrets/<secret_name>` files. For example:
 
 ```console
-$ docker run --name some-mysql -e MYSQL_ROOT_PASSWORD_FILE=/run/secrets/mysql-root -d %%IMAGE%%:tag
+$ docker run --name some-mysql -e MARIADB_ROOT_PASSWORD_FILE=/run/secrets/mysql-root -d %%IMAGE%%:tag
 ```
 
-Currently, this is only supported for `MYSQL_ROOT_PASSWORD`, `MYSQL_ROOT_HOST`, `MYSQL_DATABASE`, `MYSQL_USER`, and `MYSQL_PASSWORD`.
+Currently, this is only supported for `MARIADB_ROOT_PASSWORD`, `MARIADB_ROOT_HOST`, `MARIADB_DATABASE`, `MARIADB_USER`, and `MARIADB_PASSWORD` (and `MYSQL_*` equivalents of these).
 
 # Initializing a fresh instance
 
-When a container is started for the first time, a new database with the specified name will be created and initialized with the provided configuration variables. Furthermore, it will execute files with extensions `.sh`, `.sql`, `.sql.gz`, and `.sql.xz` that are found in `/docker-entrypoint-initdb.d`. Files will be executed in alphabetical order. `.sh` files without file execute permission are sourced rather than executed. You can easily populate your `%%IMAGE%%` services by [mounting a SQL dump into that directory](https://docs.docker.com/engine/tutorials/dockervolumes/#mount-a-host-file-as-a-data-volume) and provide [custom images](https://docs.docker.com/reference/builder/) with contributed data. SQL files will be imported by default to the database specified by the `MYSQL_DATABASE` variable.
+When a container is started for the first time, a new database with the specified name will be created and initialized with the provided configuration variables. Furthermore, it will execute files with extensions `.sh`, `.sql`, `.sql.gz`, and `.sql.xz` that are found in `/docker-entrypoint-initdb.d`. Files will be executed in alphabetical order. `.sh` files without file execute permission are sourced rather than executed. You can easily populate your `%%IMAGE%%` services by [mounting a SQL dump into that directory](https://docs.docker.com/engine/tutorials/dockervolumes/#mount-a-host-file-as-a-data-volume) and provide [custom images](https://docs.docker.com/reference/builder/) with contributed data. SQL files will be imported by default to the database specified by the `MARIADB_DATABASE` / `MYSQL_DATABASE` variable.
 
 # Caveats
 
@@ -146,31 +154,31 @@ The Docker documentation is a good starting point for understanding the differen
 2.	Start your `%%IMAGE%%` container like this:
 
 	```console
-	$ docker run --name some-%%REPO%% -v /my/own/datadir:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
+	$ docker run --name some-%%REPO%% -v /my/own/datadir:/var/lib/mysql -e MARIADB_ROOT_PASSWORD=my-secret-pw -d %%IMAGE%%:tag
 	```
 
 The `-v /my/own/datadir:/var/lib/mysql` part of the command mounts the `/my/own/datadir` directory from the underlying host system as `/var/lib/mysql` inside the container, where MySQL by default will write its data files.
 
-## No connections until MySQL init completes
+## No connections until MariaDB init completes
 
 If there is no database initialized when the container starts, then a default database will be created. While this is the expected behavior, this means that it will not accept incoming connections until such initialization completes. This may cause issues when using automation tools, such as `docker-compose`, which start several containers simultaneously.
 
 ## Usage against an existing database
 
-If you start your `%%IMAGE%%` container instance with a data directory that already contains a database (specifically, a `mysql` subdirectory), the `$MYSQL_ROOT_PASSWORD` variable should be omitted from the run command line; it will in any case be ignored, and the pre-existing database will not be changed in any way.
+If you start your `%%IMAGE%%` container instance with a data directory that already contains a database (specifically, a `mysql` subdirectory), the `$MARIADB_ROOT_PASSWORD` variable should be omitted from the run command line; it will in any case be ignored, and the pre-existing database will not be changed in any way.
 
 ## Creating database dumps
 
 Most of the normal tools will work, although their usage might be a little convoluted in some cases to ensure they have access to the `mysqld` server. A simple way to ensure this is to use `docker exec` and run the tool from the same container, similar to the following:
 
 ```console
-$ docker exec some-%%REPO%% sh -c 'exec mysqldump --all-databases -uroot -p"$MYSQL_ROOT_PASSWORD"' > /some/path/on/your/host/all-databases.sql
+$ docker exec some-%%REPO%% sh -c 'exec mysqldump --all-databases -uroot -p"$MARIADB_ROOT_PASSWORD"' > /some/path/on/your/host/all-databases.sql
 ```
 
 ## Restoring data from dump files
 
 For restoring data. You can use `docker exec` command with `-i` flag, similar to the following:
 
 ```console
-$ docker exec -i some-%%REPO%% sh -c 'exec mysql -uroot -p"$MYSQL_ROOT_PASSWORD"' < /some/path/on/your/host/all-databases.sql
+$ docker exec -i some-%%REPO%% sh -c 'exec mysql -uroot -p"$MARIADB_ROOT_PASSWORD"' < /some/path/on/your/host/all-databases.sql
 ```
