Postgraphile: How to execute complex filter queries?

[itaied246]

I have installed and launched postgraphql from npm and open graphiql.

I have a simple database schema,
but I couldn't find a way to execute complex filters like:

Querying todos from the last hour

{
  allTodos (
    createdAt {
      gt: ...
    }
  )
}

Querying tables with a certain number of legs:

{
  allTables (
    legs {
      lt: 4
    }
  )
}

Is it possible to filter like that or all of the queries are simple equality and I have to create stored procedures for this?

[mattbretl]

I recently released this: https://github.com/mattbretl/postgraphile-filter-plugins

If you have any questions or feature requests, feel free to open a new issue there.

[benjie]

(@mattbretl's plugin is for v4 of PostGraphQL which you can install via npm install -g postgraphql@next - see #506 for more info.)

Stored procedures are the only built-in way to do this currently (and are the only way to do this in v3 fullstop) but v4 allows extensions via plugins - check out @mattbretl's one above which looks like it should solve your needs, or at least provide a base!

[chadfurman]

@benjie we need to collect community extensions and projects in a central spot -- I came up with this for now: https://github.com/graphile/graphile.github.io/issues/24

[benjie]

Works for me 👍

[yonifra]

@benjie - Can you please provide an example of how to use such said plugin to get the todos from last hour as the original asker has asked? I'm a little confused on how to use such plugins in PostGraphile

[mattbretl]

@yonifra Take a look at the documentation here: https://github.com/graphile-contrib/postgraphile-plugin-connection-filter

Example:

query {
  allPosts(filter: {
    createdAt: { greaterThan: "2016-01-01" }
  }) {
    ...
  }
}

[yonifra]

This is very cool @mattbretl and seems like exactly what I was looking for.
I'm having trouble installing the plugin itself however, could you please point me to a guide on installing this plugin? I tried the CLI instructions but without lots of success...

[benjie]

Please share the issues you're facing (e.g. the errors that are being thrown) so we can help you debug it.

[yonifra]

Well, @benjie, could be that it's just a misunderstanding of my part, but I cannot get to the installation part. This is what my terminal looks like:

[yonifra]

Ooopsie, total n00bism of me... Got it working, totally forgot that the plugins part should be appended to the postgraphile connection CLI and not standalone. Thanks and sorry 😄 I'm still learning

[benjie]

The error in the screenshot is telling you that port 5000 is already in use by another process, so the server cannot listen on that port. There’s a CLI flag to listen on a different port, alternatively you can use “lsof -i tcp:5000” on OS X, or “netstat -pant” on Linux to see what’s listening on that port.

[benjie]

This issue is solved by Matt's plugin 👍