Add procedure support

[calebmer]

This PR adds support for PostgreSQL procedure execution. This will lead to a lot of awesome things like custom search functionality (#31) and authentication (#40) to name a few things that currently have open issues. This also adds a PostgreSQL native extension mechanism.

This PR is almost done, it has support for mutative procedures and query procedures, all that's missing right now is support computed column procedures.

There are a whole bunch of edge cases I'm probably missing so if you guys could try this out in your projects and report back the results that would be awesome 👍. I've published a prerelease on npm at version 1.3.0-beta.0.

Relevant files to get an understanding of how this include:

• Example procedures
• Mutation test
• Query test

[calebmer]

Ok, the code for this is pretty much done! 🎉

Computed columns work great. Before I merge and publish this I'm going to write for comments from anybody, and write some docs.

If anyone is interested in trying this out, the code is published under 1.3.0-beta.1.

[calebmer]

One thing I haven’t decided on, is should procedures like forum_example.search_posts return a connection like postNodes or not? If so a user could paginate as normal over a set returned by the procedure which could be nice.

I'm also thinking about deprecating arguments testing equality in fields like postNodes (so deprecate the headline, topic, etc. arguments on that field). Thoughs?

[ghost]

Re: whether procedures should return a connection: Yes, definitely, but how do you distinguish between procedures that behave like tables / return rows and others that are helper functions?

Other than that, it looks good!

[calebmer]

returns setof is the differentiator I think.

[calebmer]

Ok, implementing connections from setof procedures was more difficult than I thought. I'm going to leave this open so people can review if they want and I can write docs. Let’s get this merged quickly so we can iterate 👍

[calebmer]

Just finished writing documentation, so if you want to read to learn more about this feature/spell check take a look!

I'm super excited about this feature guys 😊

[ghost]

Should this be edges { node { headline, body } }?

[calebmer]

nodes is a little simpler and less intimidating for the README I think.

[ghost]

Ah, but returns the same? I've not checked the implementation yet

[calebmer]

Yep, it only returns the list, it's a shortcut if you're not interested in the cursors.

[calebmer]

Released in 1.3.0 🎉