Find feasible paths and expose missing prerequisites

Stage 2 of 4. Expand a target into its prerequisite-first sequence.

Build the mechanism

Publishing needs collection, and collection needs basics. With basics completed, the route contains collection then publishing.

Change the controls, predict the intermediate result, and compare it with the computed evidence. The visual explains this stage; grading executes your Python functions.

Exact contract

Implement path_for(index,target,completed=None), returning missing prerequisites separately from the known steps.

Read API.md, including return fields and failure behavior. The first starter supplies file I/O and HTML presentation; implement the domain functions in main.py. Keep earlier functions passing because later stages compose them.

Verify it

python3 scripts/project_test.py community-learning-path-finder --stage 2 --path learning-artifacts/community-learning-path-finder --strict

The stage tests include held-out inputs independent of the demo, boundaries, malformed data and an adversarial case. Inspect the failing assertion before changing a rule.

Failure boundary and extension

A missing prerequisite cannot be silently skipped. Explicitly completed external IDs can satisfy it.

After all four stages, run python3 cli.py samples/input.json --output my-output inside your learner workspace. Replace the sample path with your own JSON document, inspect the files and feed the exported artifact to the consumer described in the project README.