Fix monkey patching

[MonkeyCanCode]

This PR cleans up how OpenAPI-generated model imports for policies are handled. Previously, we used a runtime patch _patch_generated_models() in polaris_cli.py to work around missing policies imports. That logic has now been moved to the client generation process in generate_clients.py.

A new helper function, fix_catalog_models_init(), was added to regenerate the apache_polaris.sdk.catalog.models.__init__.py file so it correctly imports all model classes. This makes the generated client more reliable and removes the need for any runtime patching (or more monkey patching later as we have more classes added which is not part of Iceberg catalog spec).

Checklist

• 🛡️ Don't disclose security issues! (contact security@apache.org)
• 🔗 Clearly explained why the changes are needed, or linked related issues: Fixes #
• 🧪 Added/updated tests with good coverage, or manually tested (and explained how)
• 💡 Added comments for complex logic
• 🧾 Updated CHANGELOG.md (if needed)
• 📚 Updated documentation in site/content/in-dev/unreleased (if needed)

[MonkeyCanCode]

Here is the full diff between the new code and old code:

➜  polaris git:(fix_monkey_patching) diff -r client/python/apache_polaris ~/Desktop/current/polaris/client/python/apache_polaris
diff --color -r client/python/apache_polaris/cli/polaris_cli.py /Users/yong/Desktop/old/polaris/client/python/apache_polaris/cli/polaris_cli.py
49a50,90
>     def _patch_generated_models() -> None:
>         """
>         The OpenAPI generator creates an `api_client` that dynamically looks up
>         model classes from the `apache_polaris.sdk.catalog.models` module using `getattr()`.
>         For example, when a response for a `create_policy` call is received, the
>         deserializer tries to find the `LoadPolicyResponse` class by looking for
>         `apache_polaris.sdk.catalog.models.LoadPolicyResponse`.
>
>         However, the generator fails to add the necessary `import` statements
>         to the `apache_polaris/sdk/catalog/models/__init__.py` file. This means that even
>         though the model files exist (e.g., `load_policy_response.py`), the classes
>         are not part of the `apache_polaris.sdk.catalog.models` namespace.
>
>         This method works around the bug in the generated code without modifying
>         the source files. It runs once per CLI execution, before any commands, and
>         manually injects the missing response-side model classes into the
>         `apache_polaris.sdk.catalog.models` namespace, allowing the deserializer to find them.
>         """
>         import apache_polaris.sdk.catalog.models
>         from apache_polaris.sdk.catalog.models.applicable_policy import ApplicablePolicy
>         from apache_polaris.sdk.catalog.models.get_applicable_policies_response import GetApplicablePoliciesResponse
>         from apache_polaris.sdk.catalog.models.list_policies_response import ListPoliciesResponse
>         from apache_polaris.sdk.catalog.models.load_policy_response import LoadPolicyResponse
>         from apache_polaris.sdk.catalog.models.policy import Policy
>         from apache_polaris.sdk.catalog.models.policy_attachment_target import PolicyAttachmentTarget
>         from apache_polaris.sdk.catalog.models.policy_identifier import PolicyIdentifier
>
>         models_to_patch = {
>             "ApplicablePolicy": ApplicablePolicy,
>             "GetApplicablePoliciesResponse": GetApplicablePoliciesResponse,
>             "ListPoliciesResponse": ListPoliciesResponse,
>             "LoadPolicyResponse": LoadPolicyResponse,
>             "Policy": Policy,
>             "PolicyAttachmentTarget": PolicyAttachmentTarget,
>             "PolicyIdentifier": PolicyIdentifier,
>         }
>
>         for name, model_class in models_to_patch.items():
>             setattr(apache_polaris.sdk.catalog.models, name, model_class)
>
>     @staticmethod
50a92
>         PolarisCli._patch_generated_models()
diff --color -r client/python/apache_polaris/sdk/catalog/models/__init__.py /Users/yong/Desktop/old/polaris/client/python/apache_polaris/sdk/catalog/models/__init__.py
19a20,34
> # coding: utf-8
>
> # flake8: noqa
> """
>     Apache Iceberg REST Catalog API
>
>     Defines the specification for the first version of the REST Catalog API. Implementations should ideally support both Iceberg table specs v1 and v2, with priority given to v2.
>
>     The version of the OpenAPI document: 0.0.1
>     Generated by OpenAPI Generator (https://openapi-generator.tech)
>
>     Do not edit the class manually.
> """  # noqa: E501
>
> # import models into model package
27d41
< from apache_polaris.sdk.catalog.models.applicable_policy import ApplicablePolicy
39d52
< from apache_polaris.sdk.catalog.models.attach_policy_request import AttachPolicyRequest
53d65
< from apache_polaris.sdk.catalog.models.create_generic_table_request import CreateGenericTableRequest
56d67
< from apache_polaris.sdk.catalog.models.create_policy_request import CreatePolicyRequest
61d71
< from apache_polaris.sdk.catalog.models.detach_policy_request import DetachPolicyRequest
74,75d83
< from apache_polaris.sdk.catalog.models.generic_table import GenericTable
< from apache_polaris.sdk.catalog.models.get_applicable_policies_response import GetApplicablePoliciesResponse
78,79d85
< from apache_polaris.sdk.catalog.models.iceberg_error_response1 import IcebergErrorResponse1
< from apache_polaris.sdk.catalog.models.list_generic_tables_response import ListGenericTablesResponse
81d86
< from apache_polaris.sdk.catalog.models.list_policies_response import ListPoliciesResponse
86,87d90
< from apache_polaris.sdk.catalog.models.load_generic_table_response import LoadGenericTableResponse
< from apache_polaris.sdk.catalog.models.load_policy_response import LoadPolicyResponse
95,96d97
< from apache_polaris.sdk.catalog.models.notification_request import NotificationRequest
< from apache_polaris.sdk.catalog.models.notification_type import NotificationType
106,108d106
< from apache_polaris.sdk.catalog.models.policy import Policy
< from apache_polaris.sdk.catalog.models.policy_attachment_target import PolicyAttachmentTarget
< from apache_polaris.sdk.catalog.models.policy_identifier import PolicyIdentifier
121a120
> from apache_polaris.sdk.catalog.models.sql_view_representation import SQLViewRepresentation
141d139
< from apache_polaris.sdk.catalog.models.sql_view_representation import SQLViewRepresentation
150d147
< from apache_polaris.sdk.catalog.models.table_update_notification import TableUpdateNotification
160d156
< from apache_polaris.sdk.catalog.models.update_policy_request import UpdatePolicyRequest
165,166d160
< from apache_polaris.sdk.catalog.models.view_representation import ViewRepresentation
< from apache_polaris.sdk.catalog.models.view_requirement import ViewRequirement
168c162,163
< from apache_polaris.sdk.catalog.models.view_version import ViewVersion
\ No newline at end of file
---
> from apache_polaris.sdk.catalog.models.view_version import ViewVersion
>

[snazy]

Clever approach to parse Python-source-AST in Python ;)

Just one nit and a potential improvement.
But no need to add it to this PR, so +1

[snazy]

Clever :)

[snazy]

Do you think it makes sense to check for multiple classes to import from a single module (like from x.y.z import A, B, C)?

[MonkeyCanCode]

That is possible to do. But I thought OpenAPI generator always produces model files with only one public class (I may be wrong here). If there is needed, maybe we can add it as an enhancement PR instead?

[snazy]

Nah, was just a comment. Nothing to do here :)

[snazy]

Manually verified that the generated __init__.py contains all imports that the previous approach generated, just that this approach doesn't miss some types (i.e. this approach generates the complete set of import statements).

[snazy]

Nice improvement!