Way to test db connection

[tgriesser]

Would be useful...

[rbvea]

+1

[Voffkaa]

+1

[bendrucker]

For people finding this issue, this is easy enough to do manually now:

#407 (comment)

[kibertoad]

There is also a library that provides this functionality (with preset test queries for different dbs) out of the box: https://www.npmjs.com/package/knex-utils

[elhigu]

I think this can be closed or the use case needs to be specified more clearly.

Currently one can easily test the connection by just making some dummy query to the DB. That guarantees, that connection is available at that moment, but of course connection may be broken in next moment after the check.

[KaKi87]

Hello,

This issue should be reopened and a connection method should be implemented.

Thanks

[elhigu]

@KaKi87 nope. This should not be reopened and I have no idea what you mean by connection method 🤷‍♂ Please open a feature request if there is a new feature that you would like knex to have.

[yumindeckard]

The connection status should be logged in the console. Query some dummy data from database is a workaround, not the solution.

[KaKi87]

@elhigu A connection method can be a method called db.connect() for example.

[elhigu]

@yumindeckard you can add event handlers to tarn to log that kind of stuff. There are events telling if connection acquire fails for example and many other. Also if you need to log connection status on knex side you can add knex.on('query-success', ...) and knex.on('query-error', ...)event handler to print if query was success or if it failed for some reason and you can even choose to print error only if it was connection error (btw. it is also ambiguous if for example bad credentials as connection error or invalid SQL db user rights for some table / db or is it strictly the case where network or database is down).

@KaKi87 Making query is the only way to check if you are able to access your DB and having db.connect() would just wrap that dummy query to pretty much useless wrapper method which might give you false sense of security that there is stable connection... Next time you call db.connect() 10ms after it was fine the connection might be already broken.

If you need that kind of method knex nowadays offers API to add extensions so you can write separate knex-plugin for that method or you can just use knex-utils library.

EDIT:
tl;dr Knex already offers multiple ways to implement this functionality which can be bent to any use-cases we have thought... so it is useless to add one more opinionated wrapper for those to have separate API for just a single use-case, where is not even perfectly clear what it should check exactly.