Global configurable timeouts

[jalaziz]

Currently, it seems that the only way to set a query timeout is to set the query timeout on each query or to capture the executor and cancel the underlying statement after a timeout.

It would be great if a default query timeout could be configured globally.

This could use the setQueryTimeout option, but it may be possible to handle this at the execution layer to avoid issues with drivers not supporting setQueryTimeout. I have not dug too deep into the scalikejdbc source code, but from what I have see, it seems the former may be easier.

[seratch]

Having a global setting for it may be okay. However, I am not willing to have it so far. If you're using MySQL / PostgreSQL, both of them support socketTimeout parameter in JDBC URL. In my opinion, using it would be enough for most cases.

[jalaziz]

The issue with socketTimeout is that it's really a last resort. You end up killing the connection instead of just the query. Everything I've read suggests using the query timeout as first line of defense and socketTimeout as a last line of defense.

[seratch]

I see. Fair enough.

[seratch]

If we have the setting globally, having it per a connection pool would be straight-forward.

I have one concern about the possible implementation. ConnectionPoolSettings already has connectionTimeoutMillis to set timeout duration in milliseconds while queryTimeout in JDBC is in seconds. I am not comfortable with the inconsistency, but it would be acceptable for many people if we name it as queryTimeoutSeconds.

[jalaziz]

Yeah, I agree, the inconsistency is annoying. queryTimeoutSeconds is reasonable though.

I can try to take a stab at this if it doesn't require any major refactoring.

[nanajia984]

how is going with queryTimeoutSeconds? we need that feature as well

[seratch]

We haven't implemented it yet. I'm open to pull requests from the community!

By the way, I revisited this now and came to wonder if there is an equivalent setting in HikariCP. https://github.com/brettwooldridge/HikariCP

The Commons DBCP has defaultQueryTimeout. http://commons.apache.org/proper/commons-dbcp/configuration.html

If HikariCP doesn't have such, there is no other way to ignore the queryTimeout value with it (we can output warnings tho).