Allow passing DB schema as argument

[GavinRay97]

Currently if you run tusker diff database schema, it will suggest dropping other schemas.

For example, if you have some schemas which are autogenerated by tools, let's call it internal, the migration will contain DROP statements for all the tables in the internal schema if you only have a SQL schema file with tables for public.

Unfortunately this makes it unusable without manually picking through the results =/

Proposed solution:

[database]
host = "localhost"
port = 5432
user = "postgres"
password = "mypassword"
dbname = "mydatabase"
schema = "public"

Normally you could skirt this manually through passing search path in connection params, but I think the psycopg2 config is set up in a way that conflicts with this:

[database]
url = "postgresql://postgres:mypassword@localhost:5432/mydatabase?options=--search_path%3dpublic"

  File "/home/user/.local/lib/python3.7/site-packages/psycopg2/extensions.py", line 160, in make_dsn
    "you can't specify both 'database' and 'dbname' arguments")
TypeError: you can't specify both 'database' and 'dbname' arguments

[bikeshedder]

This is not part of the database URL but an option which needs to be passed to the migra.Migration constructor. I added a schema option which you can now use:

[database]
url = "postgresql://postgres:mypassword@localhost:5432/mydatabase"
schema = "public"

...or...

[database]
user = "postgres"
password = "mypassword"
host = "localhost"
port = "5432"
dbname = "mydatabase"
schema = "public"

I just release tusker 0.2.2 on PyPI which supports the database.schema option.

I was planning to add a [migra] config group in the future for more feature flags specific to the underlying migra tool. So maybe this option will need to be moved. For the time being it doesn't feel completely off in the [database] group.

[GavinRay97]

@bikeshedder Thank you! :pray:

[mariusa]

I also get the error TypeError: you can't specify both 'database' and 'dbname' arguments when running tusker diff database schema

tusker.toml

[schema]
filename = "schema.sql"

[migrations]
directory = "migrations"

[database]
url = "postgresql://marius:m@localhost:5432/db"
schema = "public"

I'd like to get schema.sql from current db, then run a diff from schema,sql to another db.

Thanks

[bikeshedder]

That error message is highly misleading. It seams that this is a psycopg2 bug.

Using a dsn together with dbname causes this error.

I'm preparing a tusker 0.3.3 release right now which works around that issue so you can use database.url and database.schema together. With tusker 0.3.2 you need to split the URL into the separate config fields: database.host, database.port, etc.

[bikeshedder]

I just released tusker 0.3.3 which fixes this problem: https://pypi.org/project/tusker/0.3.3/