Dynamically require appropriate adapter

[aguynamedryan]

Currently, a user has to explicitly specify in their Gemfile the database gem they want to with Sequelizer.

It would be great if Sequelizer could detect which adapter the user specified in their configuration and then require the appropriate database gem at runtime.

I haven't found a way to achieve this, but I'm interested in suggestions. Ultimately, I envision something like the following scenario:

• User includes gem 'sequelizer' in their gem file
• User creates a database configuration file for Sequelizer
• User runs bundle to install gems and their dependencies
• Bundler install sequelizer gem
• User can run bundle again and this time Sequelizer determines which database adapter the user specified in their configuration and tells Bundler to install that gem?
• User runs program/script that uses Sequelizer
• Sequelizer detects which database adapter is in use and requires the appropriate database gem

[mdtjr]

Hey man, just stopping through, browsing some sequel gems. (By which I mean flipping through page after page on Rubygems.org, flicking open git repos to come back to, for about two hours now.)

IIRC, you want to look in doc/opening_databases or something like that. Whatever it is, it's a file I keep thinking has 'connect' in the title but yet very much does not.

So here's your options. I'm too tired to link! But anyway say the user specifies postgres. You can connect him one of three ways: Sequel.connect(:adapter => "postgres", :database => "Pretty_ponies_development"), or Sequel.postgres(:database => "Pretty_ponies_development"), or Sequel.connect("postgres://Pretty_ponies_development").

I would say option (a) is the cleanest for your situation.

So far as the actual requiring of the "pg" gem though, if that's what you're worried about, that's just not how Sequel rolls, brah. Took me 45 minutes recently to figure out that if you "explicitly require" (paraphrasing Jeremy Evans there) the "sequel_pg" gem, it'll fuck things up. So I removed that line, and bam, smooth sailing. (The previous sentence makes more sense if you're aware "sequel_pg" is meant to replace regular, old "pg"-- not for compatibility reasons but performance ones.)

And that's the right choice on their part, imo. Installing the pg binaries and whatnot is cumbersome enough a task that you want to leave that to the programmer himself to figure out, not spend 10 hours trying to save him 5 minutes. Right? Eh? Fight for the User, but not too hard.

Peace out, RyRy

[aguynamedryan]

Maybe this? https://stackoverflow.com/questions/8492547/loading-gem-at-runtime-in-rails-3p

[aguynamedryan]

I think I just cracked this. I prototyped a little something based on this article: https://victorafanasev.info/tech/you-can-use-bundler-without-gemfile and it seems to work!

Prototype is in dynamic_gem_load branch