Support for Cloud SQL host within the dsn

[gvbgduh]

Hi,

I'm trying to use asyncpg to connect to Google Cloud SQL together with [databases](https://github.com/encode/databases/), alembic and sometimes sqlalchemy. It's quite convenient to have one database url that can be used in different cases.

But there's one problem as the Cloud SQL host is in the format /cloudsql/<project>:<region>:<db_instance>.

Unfortunately, it breaks the parsing around https://github.com/MagicStack/asyncpg/blob/master/asyncpg/connect_utils.py#L182, so the port and host cannot be distinguished unless host is explicitly passed as kwarg.

Would it be possible to consider adding the support for such a case?

Naive solution seems to be to use rpartition there, so the url
'postgresql://USER:PWD@/DB?host=/cloudsql/::<db_instance>:5432'
can be used, but I can investigate this one more thorough if seems like a reasonable case.

[elprans]

Can you show the URL you are using with sqlalchemy?

[gvbgduh]

The url is

f'postgresql://user:password@/db_name?host=/cloudsql/project-name:region:instance-name&port=5432'

so host is

/cloudsql/project-name:region:instance-name

but I have to make a workaround to pass host additionally as a kwarg, so asyncpg.connection. connect receives dsn and host as above as host from the kwargs takes precedence.

[gvbgduh]

It could be either

f'postgresql://user:password@/db_name?host=/cloudsql/project-name:region:instance-name:5432'

the result is similar.
but it's parsed as

host = "/cloudsql/project-name"
port = "region:instance-name:5432"

[leosussan]

Bumping this - am having the exact same issue.

[ioistired]

Try URL encoding the colons?

[Lawouach]

Hi there,

I'm trying to figure the state of this issue and it's not clear to me. Are we able to pass the CloudSQL /cloudsql/<project>:<region>:<db_instance> format? I tried to urlencode but I'm getting the same issue that actual string is not kep as it should.

[Lawouach]

Looking through the code a bit more. It seems the logic is to assume Host:Port from the get go (and call _parse_hostlist). Maybe a check before calling that function for the host starting with a /? Or change its name and make the check from within?