support empty password for mysql

[chungngoops]

related issue: #896

added MYSQL_ALLOW_EMPTY_PASSWORD=yes option when the passwrod is empty.

• verify all tests are passing.

[kiview]

Looks good, can you please add a test case for using an empty password?

[chungngoops]

@kiview: sure!

[kiview]

Can you please add a test for the exception condition? This needs to be done without @Rule, but instead by starting the container manually.

Please also make the sure the file is formatted correctly (see the .editorconfig file in the repository root).

[kiview]

Please use username as the object for the method invocation.

[kiview]

We can use an else if here and lose one level of nesting.

[kiview]

Let's do a try-catch here, catching ContainerException.

[kiview]

Just wondering, if we'd always need to add this and so we could put it into configure() as well?

[kiview]

I just found out, that we catch all exceptions and throw ContainerLaunchException in GenericContainer's doStart() method, so it's really not that important which exception we throw here, but ContainerLaunchException makes sense of course.

[chungngoops]

@kiview: should we check the cause of the exception to make sure that the ContainerLaunchException is thrown by this method instead of others

[kiview]

I was thinking something like this at first also. But in the end, we just want to check the public API and the container behaves as expected if we receive this exception, so I'd be good with it.

[kiview]

LGTM
You want to give it a final look @rnorth?

[rnorth]

Looks fine to me - thanks for the contribution @chungngoops !

[kiview]

Merged, thanks a lot @chungngoops.

[rui-ferreira]

Unfortunately, this doesn't work if you launch the container via JDBC URL scheme, for example, with jdbc:mysql:5.7.22://localhost:3306/databasename?user=root&password=.

The problem is that JdbcDatabaseContainerProvider gets the password from the connection URL and instantiates MySQLContainer with a default test password in case the value in the URL is empty.
This is the problematic line:
final String password = connectionUrl.getQueryParameters().getOrDefault(pwdParamName, "test");

Can you provide a fix for this case?

[rui-ferreira]

Never mind, just noticed this got fixed in #2207. :)

[aspodin]

@OverRide
protected void configure() {
optionallyMapResourceParameterAsVolume(MY_CNF_CONFIG_OVERRIDE_PARAM_NAME, "/etc/mysql/conf.d",
"mysql-default-conf");
addEnv("MYSQL_DATABASE", databaseName);
if (!MYSQL_ROOT_USER.equalsIgnoreCase(username)) {
addEnv("MYSQL_USER", username);
}
if (password != null && !password.isEmpty()) {
addEnv("MYSQL_PASSWORD", password);
addEnv("MYSQL_ROOT_PASSWORD", password);
} else if (MYSQL_ROOT_USER.equalsIgnoreCase(username)) {
addEnv("MYSQL_ALLOW_EMPTY_PASSWORD", "yes");
} else {
throw new ContainerLaunchException("Empty password can be used only with the root user");
}
setStartupAttempts(3);
}

---

addEnv("MYSQL_ALLOW_EMPTY_PASSWORD", "yes"); will be done for such configuration:
container = new CustomMySqlContainer(IMAGE_VERSION)
.withUsername("root")
.withPassword("");

but with this configuration container does not start with error message:
MYSQL_USER="root", MYSQL_USER and MYSQL_PASSWORD are for configuring a regular user and cannot be used for the root user
Remove MYSQL_USER="root" and use one of the following to control the root user password:
- MYSQL_ROOT_PASSWORD
- MYSQL_ALLOW_EMPTY_PASSWORD
- MYSQL_RANDOM_ROOT_PASSWORD