Adds javax.sql.DataSource to refreshables

[kerwin612]

Perfecting the processing method of gh-318

[spencergibb]

Why do you think javax.sql.DataSource needs to be added?

[kerwin612]

Can you take a look at #318 (comment)

Most of the time, we use interfaces, not subclasses, so I think 'javax.sql.DataSource' should in the default.

[spencergibb]

Please try with boot 2.0.4 and Finchley.SR1

[kerwin612]

I tried it, the problem is still the same, you can look at the sample code provided in #318 (comment).

[spencergibb]

I can't run that code as I don't have mysql. Care to update it so there are no external dependencies (ie H2 or similar)?

[kerwin612]

I have switched the database from mysql to h2, and the problem still exists. Please take a look.

[spencergibb]

Adding the Datasource interface does indeed fix the issue, but is still only limited to Hikari. I'd rather not add it if Hikari is not used. Flagging for team discussion.

[kerwin612]

Yes, but Hikari is used by default
😂

[spencergibb]

What we're going to try and do is inspect the implementation type of the bean, that way we don't have to add DataSource which isn't needed if it is not Hikari.

[spencergibb]

After trying to implement this, we are going to add a documentation note, but you should either set spring.cloud.refresh.extra-refreshable=javax.sql.DataSource or, more appropriately, strongly type your DataSource bean

	@Primary
	@Bean(name = "dbDataSource")
	@ConfigurationProperties(prefix = "datasource.db")
	public HikariDataSource dbDataSource() {
		return DataSourceBuilder.create().type(HikariDataSource.class).build();
	}