ActiveMapper for arbitary selects

[Former user]

I've created a patch which allows arbitary selects or existing Table instances to be used with ActiveMapper.

This can be done by giving an Alias or a Table in place of a table name.

    class mapping:
        __table__ = select(...).alias('...')

I've also added three mapper options __primary_key__, __order_by__ and __extension__. __primary_key__ and __order_by__ work like the order_by option of an ActiveMapper relationship. They can receive a string or a list of strings. These strings will be replaced by the respective columns of the Table or Alias.

During the change, I slightly refactored the existing code in order to reduce the amount of code to be added.

The new module passed all existing unit tests.

If you agree with the proposed enhancement in general, let me know if you want me to change something in particular.

Martin

[Former user]

Proposed patch

[Former user]

The patch is larger than expected because I removed all trailing whitespaces.

[Mike Bayer]

hi -

this is a very large change to ActiveMapper, which I've no problem patching in except the primary maintainers of ActiveMapper have moved on to the SQLElixir project which is meant to replace ActiveMapper. might you be better off proposing your changes on that project ?

in the case here, I dont have the resources to test these changes myself.

[Former user]

Hi Mike,

I know that Jonathan has dropped ActiveMapper in favor of Elixir. I wasn't sure whether ActiveMapper will remain an SQLAlchemy extension for backward compatibility.

As far as I can see, Elixir has been created from scratch and has not much in common with ActiveMapper. So, I don't think my changes make much sense there.

I've created this patch for personal use in order to overcome some of the restrictions of ActiveMapper. Once it worked, I thought I could share the result with others. I use the patched version with two different models. So I'm pretty sure it works ;-) Nevertheless, I understand your point.

Thanks, Martin

[Mike Bayer]

the patch doesnt apply to the current 0.4 activemapper; if the patch can be improved and maybe some unit tests added, i can patch it. the ticket can be reopened with a new patch.

[Former user]

lib/sqlalchemy/ext/activemapper.py.patch

[Former user]

test/ext/activemapper.py.patch

[Former user]

I've modified the patch so that it's compatible with SA 0.4.

There're still deprecation warnings. I couldn't figure out how to get rid of them without breaking existing code.

Since the try/except block at the beginning of the file always throws an AttributeError with SA 0.4, I removed the try block and left only the except block.

The second patch adds unittests for the new functionality introduced by the first patch. It also modifies existing tests slightly in order to get rid of deprecation warnings.

Martin