Question: many-to-many and link table support about xo HOT 3 CLOSED

I have working templates for many-many/many-to-one/one-to-many relationships, but the issue is that they are very heavily customized for a private project, and we have no intention of releasing them (they contain sensitive implementation information that cannot be released). That said, it is not difficult to create your own m/m, 1-to-m, or m-to-1 templates and use them with the tool via the --template-path CLI option.

With regards to JSON support, I have not finished writing and testing a generic JSON type that work with the lib/pq driver. That said, since JSON is recognized by xo as a "custom type", all you need to do is specify the --custom-type-package (or -C) option to use a package that has a type named JSON in it. That type needs to be able to be serialized (and unserialized) to the database by supporting the driver.Valuer interface and the sql.Scanner interface. There's a ton of documentation available online (search on Google) on writing those interfaces for Go. You can also look at the StringSlice type in the xo templates as an example of an existing sql.Scanner/driver.Valuer implementation.

For reference, this is how you pass the name of a custom type package:

xo -o models -C mytypepkg pgsql://user:pass@localhost/dbname

(note: goimports processes the Go files generated by xo, which is why this will is able to work, assuming the mytypepkg can be found by goimports)

FWIW, the reason I haven't yet written a generic JSON type for inclusion with xo is because only MySQL and PostgreSQL support JSON out of the box (as far as I know). Additionally, we don't use JSON types in our schemas. It would be fairly easy to write one, however -- and if you do, please send a pull request and I'll merge it (assuming it is written/works well)!

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@kenshaw thanks. I will give both of these a try.

It looks like JSON support should be quite straightforward for me to implement

Could you provide some guidance on what do you typically generate when there are m/m relations and link table? E.g. For tables "product", "collection", "product_collection", what additional types (and methods upon types) do you generate? If there is any skeleton code you can share, I can take it rest of the way

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I'd also be interested in a little more insight! I would like to create aggregated fields. Example:
User <-> UserAddress <-> Address

And now create a "Addresses" field for User and a "Users" field for Address... Where do I start?

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