Returns a check function for the provided javax.sql.DataSource.

Accepts the following options in the option map:

• :query-sql-params: an SQL parameter vector (as defined in next.jdbc) or a function of context that will return an SQL parameter vector containing the health check query to execute against the data source, defaults to ["SELECT 1 AS up;"].
• :query-timeout: a salutem.core/duration or a function of context that will return a salutem.core/duration representing the amount of time to wait for the query to finish before considering it failed; defaults to 5 seconds.
• :query-opts: additional options (as defined in next.jdbc) or a function of context that will return additional options to pass at query execution time; by default, includes a builder function for rows that returns unqualified kebab-cased maps; additional options are merged into the default option map.
• :query-results-result-fn: a function, of context and the results of the query, used to produce a result for the check; by default, a healthy result is returned, including the contents of the first record from the results.
• :failure-reason-fn: a function, of context and an exception, to determine the reason for a failure; by default uses failure-reason.
• :exception-result-fn: a function, of context and an exception, used to produce a result for the check in the case that an exception is thrown; by default, an unhealthy result is returned including a :salutem/reason entry with the reason derived by :failure-reason-fn and a :salutem/exception entry containing the thrown exception.

If the returned check function is invoked with a context map including a :logger key with a cartus.core/Logger value, the check function will emit a number of log events whilst executing.

Determines the failure reason associated with an exception.

This failure reason function, the default used by the check function, uses a reason of :threw-exception for all exceptions other than a java.sql.SQLTimeoutException for which the reason is :timed-out.

In the case that this default behaviour is insufficient, an alternative failure reason function can be passed to data-source-check-fn using the :failure-reason-fn option.