feat(query): set read preference to SECONDARY by default #1466
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Use-case
We think it makes sense to keep the load off the primary where possible, but here is one scenario that has stung us many times:
Given how flexible the data-browser is, it's very easy to accidentally set the
sorton a large collection on an unindexed field. Whilst there are multiple lines of defences that we can add (beforeFind in parse-server, no unindexed queries in MongoDB, etc), we think this is a good starting point for other developers.Implementation
Right now, I've just set the common find and count queries to be
SECONDARY. None of the critical flows such as writes, or even reads on Roles, ACLs etc are set to use this preference. For now, I've not added a configuration option to disable this. Happy to look into this if it's helpful?