Module 02 Activity

Scenario

The structure decision is made and it is a graph. Now it has to be designed on paper, before any node body exists.

What you build

A complete graph design as data - state fields, nodes, edges and the condition on every edge - plus the two checks that design makes possible.

Steps

1. List the state fields with their types and, for each, which node owns it.
2. List the nodes, one line each, describing exactly what changes in the state. If a description needs the word 'and', split the node.
3. List every edge with its condition. Fixed edges say 'always'.
4. Check every cycle has a counter in the state and a ceiling in a router.
5. Check every node with a side effect, and confirm no retry path can reach it twice.
6. Implement the graph and confirm each node is testable with a plain dictionary, no graph required.

Evidence to hand in

• The design as data: state, nodes, edges with conditions.
• The two structural checks with their results.
• The implemented graph.
• One node test that constructs a dictionary and asserts on the returned update.

Review checklist

• Every node description is one job - no 'and'.
• Every edge carries a condition, including the fixed ones.
• Every cycle has a counter and a ceiling.
• Every side-effecting node is identified, and the retry path is checked against it.
• At least one node test runs without constructing a graph.

Mark complete