Add memory subgraph example and reporting integration

[jfrench9]

Summary

Introduces a new memory subgraph example demonstrating how to create and manage memory-based subgraphs, along with integration points for reporting this capability to Dagster. This is a chore/example addition that expands the custom graph demo suite.

Key Accomplishments

• New memory subgraph example: Added a comprehensive example (07_memory_subgraph.py) showcasing memory subgraph creation patterns, significantly expanding the custom graph demo library with ~540 lines of example code
• Demo entrypoint update: Updated the custom graph demo main module to include and expose the new memory subgraph example
• Subgraph router registration: Extended the subgraphs router to register the memory subgraph capability, enabling it to be discovered and utilized within the broader graph infrastructure
• Audit logging enhancement: Added audit logging support for the new memory subgraph operations to maintain security observability

Breaking Changes

None. This is an additive change that introduces a new example and extends existing modules without modifying current behavior.

Testing Notes

• Verify the new memory subgraph example runs correctly through the custom graph demo entrypoint
• Confirm the subgraph router properly registers and routes to the new memory subgraph
• Validate that audit log entries are correctly emitted for memory subgraph operations
• Ensure existing graph demos and subgraph functionality remain unaffected by the additions

Infrastructure Considerations

• The new subgraph type should be reflected in any orchestration or pipeline management systems (e.g., Dagster) that discover and report on available graph types
• Audit logging infrastructure should be verified to handle the new event types without requiring schema or storage changes
• No new dependencies or deployment configuration changes are expected

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🤖 Generated with Claude Code

Branch Info:

• Source: chore/subgraph-memory-example
• Target: main
• Type: chore

Co-Authored-By: Claude noreply@anthropic.com

[jfrench9]

@claude please review this PR

[claude]

Claude finished @jfrench9's task in 2m 10s —— View job

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PR Review: Add memory subgraph example and reporting integration

• Gather context and understand request
• Read changed files
• Analyze code quality and provide feedback

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Overall this is a clean, additive PR. The example is well-structured and the Dagster reporting integration follows the established pattern in reporting.py. A few issues worth addressing below.

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Critical: origin/main was already broken before this PR

robosystems/routers/graphs/subgraphs/main.py on main references SecurityEventType.SUBGRAPH_CREATED (lines 355 and 394), but that enum value didn't exist in audit_logger.py until this PR adds it. This means main had a broken AttributeError at import time. This PR implicitly fixes it, but it should be called out explicitly — and ideally the previous PR that introduced the router code should have included this enum addition.

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Issues

1. 07_memory_subgraph.py — --credentials-file arg ignored for credential loading

load_credentials() hardcodes CREDENTIALS_FILE rather than accepting a path argument:

# examples/custom_graph_demo/07_memory_subgraph.py:61-66
def load_credentials() -> dict:
    if not CREDENTIALS_FILE.exists():  # ← always uses the constant
        ...

# main():
credentials = load_credentials()      # ← ignores args.credentials_file
graph_id = get_graph_id(credentials_path, DEMO_NAME)  # ← credentials_path used here only

Passing --credentials-file /custom/path.json will load credentials from .local/config.json instead. Other scripts in this suite (e.g., 01_setup_credentials.py) likely pass the path through to the loader. Fix this →

2. main.py — step 7 runs unconditionally, will fail on re-runs

Step 6 (document upload) is guarded by a directory existence check. Step 7 runs unconditionally:

# examples/custom_graph_demo/main.py:172-179
# Step 7: Create memory subgraph
step7_args = [...]
run_script("07_memory_subgraph.py", step7_args)  # ← no guard

07_memory_subgraph.py calls sys.exit(1) if subgraph creation fails (e.g. duplicate name on re-run), which propagates through run_script and aborts the whole demo. Consider either adding --skip-memory-subgraph flag or handling the "already exists" case gracefully in the example script. Fix this →

3. subgraphs/main.py — fork path missing Dagster reporting

The new Dagster report_asset_materialization call is only in the non-fork code path. Subgraphs created via fork_parent=True return early (line ~377) without reporting:

# robosystems/routers/graphs/subgraphs/main.py
if request.fork_parent:
    ...
    return response   # ← no Dagster reporting here

Forked subgraphs won't appear in Dagster observable assets. Intentional or oversight?

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Minor Notes

4. SUBGRAPH_DELETED added but unused

SUBGRAPH_DELETED = "subgraph_deleted" is added to the enum but nothing in this PR emits it. Fine as forward-looking prep, but if there's no deletion endpoint yet it could be left until that's implemented to keep the enum tidy.

5. asset_key="user_subgraph_creation" — verify asset exists in Dagster definitions

The hardcoded string "user_subgraph_creation" should match an observable source asset key defined somewhere in robosystems/dagster/. A missing definition won't raise an error (the call is wrapped in try/except) but the materialization will be silently orphaned. Worth a quick grep to confirm it's defined.

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What's Good

• The example script is thorough and well-organized — covers creation, seeding (Concepts, Observations, Sessions), relationships, and verification queries
• The Dagster reporting block correctly wraps the call in try/except with a logger.warning, consistent with the established pattern in reporting.py
• SUBGRAPH_CREATED is already used in the router on main — adding it to the enum here actually fixes a latent AttributeError
• Emojis in the example script are appropriate per CLAUDE.md (examples/ is exempt from the no-emoji rule)
• No new dependencies, migrations, or breaking changes

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