fix: add back imports for migration_runner

[lsh950919]

Add back migration_runner import for adk migrate session

Please ensure you have read the contribution guide before creating a pull request.

Link to Issue or Description of Change

1. Link to an existing issue (if applicable):

• Related: The "adk migrate session" command has been removed from the cli #4107

2. Or, if no issue exists, describe the change:

Problem:
The previous pr to add back migrate cli (8fb2be2) forgot to add back the imports required for the migration cli, causing
Migration failed: name 'migration_runner' is not defined
error.
This pr requests to add back the required import (from ..sessions.migration import migration_runner) in order to use the adk migrate session cli functionality

Solution:
Is just an import issue, just want others to be able to use the functionality after the major update on DB schema in version 1.22

Testing Plan

1. Added back the import
2. installed using uv pip install -e .
3. ran adk migrate session

adk migrate session --source_db_url "postgresql+psycopg://USER:PASSWORD@HOST:5432/a" --dest_db_url "postgresql+psycopg://USER:PASSWORD@HOST:5432/b"

Unit Tests:

• [N] I have added or updated unit tests for my change.
• [Y] All unit tests pass locally.

Please include a summary of passed pytest results.

Manual End-to-End (E2E) Tests:

Please provide instructions on how to manually test your changes, including any
necessary setup or configuration. Please provide logs or screenshots to help
reviewers better understand the fix.

Checklist

• [Y] I have read the CONTRIBUTING.md document.
• [Y] I have performed a self-review of my own code.
• [N] I have commented my code, particularly in hard-to-understand areas.
• [N] I have added tests that prove my fix is effective or that my feature works.
• [Y] New and existing unit tests pass locally with my changes.
• [Y] I have manually tested my changes end-to-end.
• [Y] Any dependent changes have been merged and published in downstream modules.

Additional context

Add any other context or screenshots about the feature request here.

[gemini-code-assist]

Summary of Changes

Hello @lsh950919, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a critical regression that prevented the adk migrate session command from executing due to a missing import for migration_runner. The change simply re-introduces the necessary import statement, thereby restoring the intended functionality for database migrations, which is particularly important following recent major database schema updates. This ensures the CLI tool works as expected for users needing to manage their database schemas.

Highlights

• Fixes NameError for migration_runner: This pull request resolves a NameError: name 'migration_runner' is not defined error that occurred when attempting to use the adk migrate session CLI command.
• Restores adk migrate session functionality: By re-adding a missing import statement, this PR ensures that the adk migrate session command is fully functional again, allowing users to perform necessary database migrations.
• Addresses regression from previous PR: The issue was a regression introduced in a prior pull request (8fb2be2) that aimed to re-enable the adk migrate CLI but overlooked the required import.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request correctly addresses a NameError in the adk migrate session command by adding the missing import for migration_runner. The fix is simple and effective. I've included one suggestion to improve code style by sorting the local imports, which will enhance readability and maintainability.

[wuliang229]

Already fixed in commit 6c0bf85. Thanks though!