Add compatibility with CockroachDB

[stevecookform3]

Cockroachdb (https://github.com/cockroachdb/cockroach) is compatible with the postgres protocol, however the provider currently fails validating the versions

Error initializing PostgreSQL client: error detecting capabilities: error parsing version: Invalid character(s) found in major number "CCL"

Probably just requires tweaking in https://github.com/terraform-providers/terraform-provider-postgresql/blob/master/postgresql/config.go

[robert-s-lee]

CRDB returns the following

root=# select version();
                                       version
--------------------------------------------------------------------------------------
 CockroachDB CCL v19.1.3 (x86_64-apple-darwin14, built 2019/07/08 18:19:30, go1.11.6)

[cyrilgdn]

Hi @stevecookform3 , thanks for opening this issue.

We could fix the version detection but the problem is that we need a "Postgresql" version to determine which features are enabled or not (see https://github.com/terraform-providers/terraform-provider-postgresql/blob/master/postgresql/config.go#L42-L73)

I don't know CockroachDB at all yet, is there some kind of compatibility mapping ? (Like version X of CockroachDB is compatible with version Y of Postgresql)

Meanwhile, in the next version of this provider (which will be released in the next days), you should be able to set the expected_version to a Postgres version (e.g: 12.1) in the provider configuration. This will avoid the automatic version detection.

However, I don't known CockroachDB and I don't know what's the compatibility

[stevecookform3]

being able to override this with expected_version sounds like a good workaround for now.
(not least because i dont think terraform is the right place to maintain compatibility tables on third party databases)

[cyrilgdn]

being able to override this with expected_version sounds like a good workaround for now.
(not least because i dont think terraform is the right place to maintain compatibility tables on third party databases)

Thanks for your answer. I close this issue for now.
(I'll try to test CockroachDB anyway one day if I find time and courage 😄 )